Dissertations / Theses: 'Anurans'

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Shilton, Catherine Margaret. "Corneal lipid deposition in anurans." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 2000. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape2/PQDD_0020/NQ55639.pdf.

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Sheridan, Jennifer Ann. "Variation in Southeast Asian anurans." Diss., Connect to a 24 p. preview or request complete full text in PDF format. Access restricted to UC campuses, 2008. http://wwwlib.umi.com/cr/ucsd/fullcit?p3296894.

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Thesis (Ph. D.)--University of California, San Diego, 2008.
Title from first page of PDF file (viewed Apr. 7, 2008). Available via ProQuest Digital Dissertations. Vita. Includes bibliographical references (p. 127-138).

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Watters, Kayla Christine. "Community Structure and Epizootic Infection Prevalence of Northern Wisconsin Anurans." Wright State University / OhioLINK, 2018. http://rave.ohiolink.edu/etdc/view?acc_num=wright1526041783398815.

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Simons, Verne F. H. "Morphological Correlates of Locomotion in Anurans: Limb Length, Pelvic Anatomy and Contact Structures." Ohio : Ohio University, 2008. http://www.ohiolink.edu/etd/view.cgi?ohiou1212673879.

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Lillie, Mette Christine. "Major histocompatibility complex diversity in anurans." Thesis, The University of Sydney, 2015. http://hdl.handle.net/2123/14000.

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The Major Histocompatibility Complex (MHC) is a large gene complex vital to the vertebrate immune response. The antigen-presenting molecules of the MHC class I and class II are involved in the immune surveillance of intracellular and extracellular pathogens, respectively. The regions of the MHC involved in peptide binding and presentation are often highly polymorphic and have high allelic variation within populations. High MHC diversity is theorised to provide immunogenetic competence to a population, and these genes have become a popular adaptive genetic marker in population studies, often with a conservation context. This thesis presents the characterisation of MHC diversity in two anuran species undergoing very different population histories: the cane toad (Rhinella marina), undergoing range expansions over the course of the Australian invasion; and the New Zealand endemic Hochstetter’s frog (Leiopelma hochstetteri), where populations are highly fragmented. In both cases, I investigate MHC diversity alongside neutral genetic diversity to infer the relative influences of neutral genetic forces, predominately drift, and selection in shaping allelic variation. This involved characterisation of the class I and class II in the cane toad, prior to completing a diversity study utilising genetic markers from both classes. I also characterised a class II beta gene in the Hochstetter’s frog to characterise diversity across 5 populations. The characterisation of the cane toad class I revealed a single classical locus, and an expansion of non-classical loci. This is similar to the class I organisation found in the model anuran, Xenopus laevis and across its subfamily Xenopodinae. The cane toad and X. laevis diverged around 230MYA. The characterisation of the cane toad class II revealed four class II alpha loci and three class II beta loci. It also revealed the expression of MHC class II splice isoforms at several alpha and beta genes. This is the first observation of alternative splicing in the MHC of any anuran species. The diversity of the classical class I (UA) and class II beta gene (DAB) was studied in the source of the Australian introduction (Hawaii), in a long-colonised site (Cairns) and a site on the invasion front (Timber Creek). I found that little diversity was lost as a result of the introduction and that Cairns was highly genetically representative of Hawaii. I found genetic drift acting at the invasion front, decaying genetic diversity at microsatellite markers and the UA locus in the dispersing cane toads. DAB diversity was maintained, however. Selection has retained all three DAB alleles across the toad invasion, likely mediated by pathogenic bacteria and parasites infecting the population. I found very high MHC class II DAB polymorphism in the Hochstetter’s frog across 5 sampled populations. Populations showed extreme differentiation; only two DAB alleles were shared by more than one population. Populations generally had high DAB diversity, except Otawa. The Otawa population had only two DAB alleles present. Combined with low microsatellite diversity, Otawa has likely undergone a recent decline, which has impacted genetic diversity. Low immunogenetic diversity in Otawa may predispose this population to a greater risk of extinction from emergent disease.

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Morrison, Fiona Clare. "Altitudinal Variation in the Life History of Anurans in Southeast Queensland." Thesis, Griffith University, 2002. http://hdl.handle.net/10072/366730.

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Global declines and disappearances of amphibians from high altitude, pristine habitats have been reported in recent years. To date the cause of many of these declines and/or disappearances has not been identified. Although it is well documented that life history characteristics of temperate amphibians are influenced by altitude (due to systematic variation of temperature with altitude), little work has been carried out on the effects of altitude on Australian anurans. This lack of ecological data is a major impediment to identifying the causal factors responsible for amphibian declines. Due to differences in life history characteristics, high altitude populations may be less resilient than their lowland counterparts and subsequently may be more vulnerable to extinction. Consequently, the main aim of this study was to determine whether altitude influenced life history characteristics and ultimately population resilience of anurans in the southeast Queensland region. Six anuran species; Litoria chloris, L. lesueuri, L. pearsoniana (Anura: Hylidae), Mixophyes fasciolatus, M. fleayi and M. iteratus (Anura: Myobatrachidae) were studied over three field seasons (1997-1999) in 18 sites of varying altitude (100-950m) in the southeast Queensland region. The life history characteristics examined were: activity and breeding season length, fecundity and egg size, number of clutches produced per season, tadpole growth and development rates, longevity, age at maturity, reproductive life span, average lifetime fecundity, survival and recapture rates. The data were collected using a combination of field-based surveys (body sizes, clutch sizes, and survival and recapture rates), museum specimen dissections (clutch and egg sizes), reciprocal transplant field experiments (tadpole growth and development rates) and skeletochronology (longevity, age at maturity, reproductive lifespan and average lifetime fecundity). On average, high altitude populations of all species had shorter breeding and activity seasons than low altitude populations (up to 10 weeks less in some cases). The magnitude of the difference in breeding season length varied among years depending on the average temperature and rainfall for the year; i.e. differences appeared greater in warmer and wetter years. Within a population males had longer breeding and activity seasons than females. Although breeding season length varied with altitude, the number of nights that individuals were active within the breeding season did not vary; i.e. low altitude populations were not active for more nights despite having a longer breeding season. This result was attributed to the absence of a relationship between individual activity and environmental variables (air temperature, rainfall, etc.) in many of the populations. Generally, intraspecific clutch size did not vary significantly with altitude. This result was due to the absence of a significant relationship between female body size and altitude (as clutch size is proportional to female body size). Egg size also did not vary with altitude however, suggesting egg size may be canalized (i.e. fixed) in these species. Results also suggest that females of these species only produce one clutch of eggs per season. Interspecific differences in reproductive characteristics largely reflected differences in reproductive mode, larval habitat and female body size. Altitude negatively influenced growth and development rates in L. chloris and development rates in L. pearsoniana. Tadpoles raised at high altitudes were also generally larger at each Gosner Development Stage in both species. The results of the reciprocal transplant experiments suggested that most of the variation in growth and development rates was due to environmental factors (water temperature) rather than genetic or maternal factors. Altitude or genetic factors did not significantly affect tadpole survival in either species. The results suggest that tadpoles occurring at high altitudes take longer to reach metamorphosis and do so at a larger size than their lowland counterparts. With the exception of L. lesueuri, skeletochronology was suitable for age estimation in the study species. Altitude had a significant effect on the age at maturity or longevity in some of the species, however there were trends toward older individuals and older ages at maturity in high altitude populations for the remaining species. Females were generally older than males for all species and in the case of longer-lived species (i.e. Mixophyes spp.) also tended to be older when breeding for the first time. The large overlap of body sizes of individuals of different ages demonstrates that body size is a poor indicator of age in these species. This is the first study to estimate average lifetime fecundity for more than one amphibian species and/or population. The results suggest that the absence of significant altitudinal variation in the average lifetime fecundity of different populations is due to tradeoffs made by females (current reproduction vs. survival). There was no significant altitudinal variation in annual survival and recapture rates in any of the species, and generally there was no difference in the survival and recapture rates of males and females in each population. Within a year, monthly survival and recapture rates were more variable at low than high altitudes and this was attributed to the longer breeding season of low altitude populations. The results did not support previous studies that suggested there was a size bias in survival and recapture rates. The shorter breeding seasons, slower growth and development rates, older age at maturity and greater longevity found in the high altitude study populations will result in increased generation time in those populations. In turn, increased generation time can cause high altitude populations to be less resilient (i.e. population takes longer to return to equilibrium after a disturbance away from equilibrium) (Pimm et al. 1988, Pimm 1991) and ultimately more vulnerable or prone to extinction or decline. The majority of unexplained global amphibian declines have occurred at high altitudes in tropical and subtropical areas. These latitudinal patterns may be explained by the narrow range of environmental tolerances exhibited by tropical organisms resulting in mountains being effectively “higher” in the tropics. Consequently, high altitude tropical species are likely to be even more vulnerable than temperate species occurring at similar altitudes. Further work on the effects of geographic variation, especially interactions between altitude and latitude are needed to evaluate the hypotheses for the causes of these declines and disappearances.
Thesis (PhD Doctorate)
Doctor of Philosophy (PhD)
School of Environmental and Applied Science
Science, Environment, Engineering and Technology
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Oliveira, Thiago Alves Lopes de [UNESP]. "Anurofauna em uma área de ecótono entre Cerrado e Floresta Estacional: diversidade, distribuição e a influência de características ambientais." Universidade Estadual Paulista (UNESP), 2012. http://hdl.handle.net/11449/87577.

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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)
Dois dos maiores desafios da ecologia de comunidades são encontrar padrões a respeito dos grupos de espécies que vivem em seus ambientes e entender os processos que produzem os padrões atuais. Nesse sentido, estudos que descrevam as comunidades biológicas, explorando os padrões de distribuição das espécies em diferentes escalas espaciais e temporais e que analisem o que poderia influenciar essa distribuição, são de grande interesse geral e nos fornecem importantes informações das espécies e habitats que conhecemos. Dessa forma, esse trabalho visa compreender a estrutura de uma comunidade de anfíbios anuros em uma área de ecótono entre cerrado e floresta estacional no nordeste do Estado de São Paulo (Estação Ecológica de Jataí – EEJ). Essas fisionomias no Estado de São Paulo sofreram intensamente a ação de fragmentação e perda de habitat, devido principalmente à urbanização, pecuária e cultivo de monoculturas como a cana-de-açúcar. A área de estudo é a maior unidade de conservação do bioma Cerrado no Estado de São Paulo e apresenta uma interessante área de estudo devido à configuração espacial da área, uma transição entre mosaico de fisionomias de Cerrado e Floresta Estacional. O objetivo do trabalho foi descrever a diversidade da anurofauna terrícola e entender os padrões de distribuição de abundâncias das espécies e de coocorrência. Além desses objetivos, e devido ao viés encontrado na maioria dos trabalhos de ecologia de comunidades que avaliam a influência de descritores dos habitats aquáticos sobre a riqueza e abundância de anfíbios anuros, nosso trabalho também visa compreender os efeitos das características dos habitats terrestres sobre a abundância da anurofauna avaliando quais características do meio físico, como cobertura do dossel, porcentagem...
Two of the biggest challenges in community ecology are the capacity to find patterns in groups of species that live in their environment and to understand the processes that produce these patterns. Accordingly, studies describing the biological communities, exploring their species distribution patterns at different spatial and temporal scales and analyzing what factors influence the distribution of species, are of great interest and provide important information of the species and habitats that we know. Thus, this study aims to understand the structure of a community of frogs and toads in an area of ecotone between savanna and semideciduous forest in the northeastern of São Paulo state (Jataí Ecological Station - JEE). These physiognomies in the state of Sao Paulo suffered intense fragmentation and habitat loss, primarily due to urbanization, livestock and cultivation of monocultures as sugarcane. The study area are the largest protected area of Cerrado in São Paulo state, and presents an interesting area of study due to the spatial configuration of transition between a mosaic of Cerrado and a Floresta Estacional. The aim of this study was to describe the diversity of terrestrial frogs and toads and to understand the patterns of species abundance distributions and co-occurrence. Besides these goals, and due to the bias found in most studies of community ecology to assess the influence of descriptors of aquatic habitats on the richness and abundance of amphibians, our work also aims to understand the effects of the features of terrestrial habitats on the frog’s abundance examining which features of the physical environment, such as canopy cover, percent cover soil, distance from the nearest body of water, could better predict the abundance of anurans. For this purpose, we installed pitfall traps with drift fences... (Complete abstract click electronic access below)

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Valdujo, Paula Hanna. "Diversidade e distribuição de anfíbios no Cerrado: o papel dos fatores históricos e dos gradientes ambientais." Universidade de São Paulo, 2011. http://www.teses.usp.br/teses/disponiveis/41/41134/tde-13052011-153438/.

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A integração de fatores contemporâneos locais e procesos biogeográficos fornece uma visão ampla e promissora a respeito da diversidade de espécies e seus padrões de diversidade. Utilizando ferramentas recentes para análises espaciais, eu integro fatores históricos e contemporâneos para analisar a distribuição e beta diversidade espécies de anuros do Cerrado. Forneço informações atualizadas a respeito da composição e distribuição das espécies de anuros no Cerrado, com base em um extensivo levantamento em coleções zoológicas e estudos de campo. Analiso a distribuição e beta diversidade em um contexto histórico, enfocando as relações do Cerrado com seus domínios vizinhos, e suas condições ambientais. Registrei 204 espécies de anuros no Cerrado, das quais 50% são endêmicas. Espécies que ocorrem no Cerrado e mais um domínio apresentam alta estruturação espacial, na qual espécies amazônicas estão restritas à porção noroeste e as espécies atlânticas estão restritas à porção sudeste do Cerrado. Registrei espécies endêmicas em quase todas as localidades e em todas as regiões, enquanto espécies de distribuição restrita ocorrem apenas em regiões montanhosas no centro, sudeste e sudoeste do Cerrado. Gêneros originado na Mata Atlântica e Amazonia estão distribuídos em um padrão de \"tabuleiro de xadrez\" dentro do Cerrado, e co-ocorrem menos do que seria esperado ao acaso. Essa estruturação espacial no Cerrado é influenciada pela ação combinada das condições ambientais e restrições históricas: gêneros atlânticos estão predominantemente distribuídos em áreas de montanha, com baixa precipitação e próximas ao limite com a Mata Atlântica, enquanto gêneros amazônicos estão distribuídos em vales mais próximos ao limite com a amazônia. Da mesma forma, os padrões de beta diversidade no Cerrado parece estar fortemente influenciados pelos gradientes ambientais, uma vez que metade da dissimilaridade na composição de espécies entre taxocenoses foi explicada por estes preditores. Espécies endêmica responderam às condições ambientais regionais de forma mais intensa que todas as espécies em conjunto. A resposta das espécies endêmicas parece estar relacionada na similaridade do ambiente em que ocorrem em relação aos domínios vizinhos, uma vez que suas espécies-irmãs estão principalmente distribuídas por estas regiões. Meus resultados reforçam a importância de se considerar a história biogeográfica das linhagens nas análises dos padrões regionais de disversidade. Demonstro também que a heterogeneidade na distribuição das espécies de anuros pode ter uma base histórica, que interage com restrições atuais, como o clima, disponibilidade de habitat e interações ecológicas na montagem de comunidades.
Integrating local contemporary factors and biogeographic processes allows a promising and broad view on species diversity and distribution patterns. Building on the development of new tools for spatial analysis, I integrate historical and contemporary factors that may explain species distribution and beta diversity patterns of anuran amphibians in Brazilian Cerrado. Especifically, I update information about species composition and distribution of anurans in the Cerrado, based on an extensive search in zoological collections and fieldwork. I analyze distribution and beta diversity in a historical framework, focusing on the relationship of the Cerrado with its adjoining domains, and its environmental conditions. I found 204 anuran species occurring within the Cerrado, from which 50% are endemics. Species occurring in the Cerrado and one more domain present a highly structured spatial pattern, in which Amazonian species are restricted to the northwestern part of the Cerrado and Atlantic species are restricted to the southeastern part. I found Cerrado endemics in most of the localities, in all regions, whereas narrow endemics are restricted to mountain ranges in central, southeastern, and southwestern Cerrado. Cerrado anuran genera originated in Atlantic Forest and Amazon are distributed in a checkerboard pattern, and co-occur less than it would be expected by chance. This spatial structure within the Cerrado is influenced by the interplay of environmental conditions and historical constrains: Atlantic genera are mostly distributed in mountainous and upland areas, with low precipitation and closer to the boundaries of Atlantic Forest, whereas Amazonian genera are distributed in valleys closer to the boundaries of the Amazon. Similarly, patterns of beta diversity in the Brazilian Cerrado appear to be strongly influenced by the environmental gradients, since half of the dissimilarity in species composition was explained by these predictors. Endemic species responded to regional environmental conditions stronger than all species. Endemics may be responding to environment based on how similar they are to the conditions of adjoining phytogeographical domains, since their sister-species are mostly distributed in these regions. My results reinforce the importance of taking biogeographical history into account when analyzing spatial patterns of species diversity at a regional scale. I also show that the heterogeneity in anuran distribution in the Cerrado may have a historical basis, which interacts with present-day constraints, such as climate, habitat availability and ecological interactions, to shape local and regional assemblages.

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Aguiar, Aline. "Metazoários endoparasitas de anuros em uma área de transição entre Cerrado e Mata Atlântica composição, estrutura e variáveis relacionadas /." Botucatu, 2017. http://hdl.handle.net/11449/151833.

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Orientador: Reinaldo José da Silva
Resumo: Este estudo primeiramente investigou e descreveu a diversidade de parasitas metazoários associados a 26 espécies de anuros em uma região de transição entre Mata Atlântica e Cerrado no noroeste paulista, Brasil. Em seguida, procuramos analisar os padrões de agregação e distribuição das populações parasitárias nas diferentes espécies de hospedeiros bem como a estrutura e composição da comunidade componente. Também foram reportados novos registros de ocorrência em anuros do Brasil e considerações taxonômicas para algumas espécies de helmintos. As 26 espécies de anuros apresentaram um total de 40 taxa de parasitas metazoários: Aplectana hylambatis, Aplectana membranosa, Brevimulticaecum sp. (larva), Cosmocerca cf. chilensis, Cosmocerca parva, Cosmocerca podicipinus, Cosmocercidae gen. sp., Falcaustra mascula, Ochoterenella digiticauda, Ochoterenella sp., Oswaldocruzia mazzai, Oxyascaris caudacutus, Oxyascaris sp., Parapharyngodon cf. alvarengai, Physaloptera sp. (larva), Raillietnema minor, Raillietnema sp., Rhabdias sp.1, Rhabdias sp.2, Rhabdias sp.3, Schrankiana formosula, Spiroxys sp. (larva) (Nematoda), Centrorhynchidae gen. sp. (cisto), Cistacanto não identificado (Acanthocephala), Cylindrotaenia americana (Cestoda), Brachycoelium salamandrae, Bursotrema sp. (metacercária), Catadiscus marinholutzi, Catadiscus propinquus, Catadiscus sp., Clinostomum sp., Gorgoderina diaster, Gorgoderina sp., Heterodiplostomum sp. (metacercária), Lophosicyadiplostomum sp. (metacercária), metac... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: In the present study, we firstly investigated and described the diversity of metazoan parasites associated with 26 anuran species from a transitional area between Mata Atlântica and Cerrado in Northwest of São Paulo State, Brazil. Thereafter, we searched for aggregation and distribution patterns of parasite populations from different host species as well as the structure and composition of component communities. Also, we reported new records of occurrence in Brazilian anurans and taxonomic considerations for some parasite species. The 26 anuran species presented a total of 40 metazoan parasite taxa: Aplectana hylambatis, Aplectana membranosa, Brevimulticaecum sp. (larvae), Cosmocerca cf. chilensis, Cosmocerca parva, Cosmocerca podicipinus, Cosmocercidae gen. sp., Falcaustra mascula, Ochoterenella digiticauda, Ochoterenella sp., Oswaldocruzia mazzai, Oxyascaris caudacutus, Oxyascaris sp., Parapharyngodon cf. alvarengai, Physaloptera sp. (larvae), Raillietnema minor, Raillietnema sp., Rhabdias sp.1, Rhabdias sp.2, Rhabdias sp.3, Schrankiana formosula, Spiroxys sp. (larvae) (Nematoda), Centrorhynchidae gen. sp. (cyst), Unidentified cystacanth (Acanthocephala), Cylindrotaenia americana (Cestoda), Brachycoelium salamandrae, Bursotrema sp. (metacercariae), Catadiscus marinholutzi, Catadiscus propinquus, Catadiscus sp., Clinostomum sp., Gorgoderina diaster, Gorgoderina sp., Heterodiplostomum sp. (metacercariae), Lophosicyadiplostomum sp. (metacercariae), Unidentified metacercariae, ... (Complete abstract click electronic access below)
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Willens, Scott. "Effects of percutaneous malathion absorption in anurans." NCSU, 2005. http://www.lib.ncsu.edu/theses/available/etd-11022005-110637/.

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The objective of this research was to characterize the percutaneous absorption of the organophosphorous pesticide, malathion, across the skin of bullfrogs (Rana catesbeiana) and marine toads (Bufo marinus) using in vitro models. An established mammalian model for percutaneous absorption, the two-compartment Teflon flow-through diffusion cell assay, was adapted to anuran skin to examine species and anatomical site differences in absorption and partitioning of C¹⁴-radiolabeled malathion. Malathion absorption was greater across the ventral skin compared to dorsal skin in both bullfrogs and marine toads but did not differ significantly between species. The issue of short-term storage and viability of anuran skin for diffusion cells was examined using glycerol preservation and cryopreservation techniques. Bullfrog skin viability was retained for 28 days, while marine toad skin viability significantly decreased after 7-10 days. A novel in vitro model, the harvested perfused anuran limb (HPAPL) preparation, which maintained an intact microvasculature to the skin, was developed. The HPAPL represented an improvement over diffusion cells by retaining the anatomic and physiologic integrity of the skin. Doppler ultrasound was used to determine the perfusion rate for the HPAPL by measuring the physiologic blood flow of the pelvic limb in vivo. In addition to the characterization of the percutaneous absorption of malation in anurans, effects of sublethal doses on brain acetyl cholinesterase activity in bullfrogs and marine toads, were examined using a modified Ellman spectrophotometric technique. Sensitivity to environmental toxins make anurans potentially important animal models for studying the impacts of organophosphorous insecticide contamination of the environment.

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Morrison, Fiona Clare, and n/a. "Altitudinal Variation in the Life History of Anurans in Southeast Queensland." Griffith University. School of Environmental and Applied Science, 2002. http://www4.gu.edu.au:8080/adt-root/public/adt-QGU20031125.120847.

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Global declines and disappearances of amphibians from high altitude, pristine habitats have been reported in recent years. To date the cause of many of these declines and/or disappearances has not been identified. Although it is well documented that life history characteristics of temperate amphibians are influenced by altitude (due to systematic variation of temperature with altitude), little work has been carried out on the effects of altitude on Australian anurans. This lack of ecological data is a major impediment to identifying the causal factors responsible for amphibian declines. Due to differences in life history characteristics, high altitude populations may be less resilient than their lowland counterparts and subsequently may be more vulnerable to extinction. Consequently, the main aim of this study was to determine whether altitude influenced life history characteristics and ultimately population resilience of anurans in the southeast Queensland region. Six anuran species; Litoria chloris, L. lesueuri, L. pearsoniana (Anura: Hylidae), Mixophyes fasciolatus, M. fleayi and M. iteratus (Anura: Myobatrachidae) were studied over three field seasons (1997-1999) in 18 sites of varying altitude (100-950m) in the southeast Queensland region. The life history characteristics examined were: activity and breeding season length, fecundity and egg size, number of clutches produced per season, tadpole growth and development rates, longevity, age at maturity, reproductive life span, average lifetime fecundity, survival and recapture rates. The data were collected using a combination of field-based surveys (body sizes, clutch sizes, and survival and recapture rates), museum specimen dissections (clutch and egg sizes), reciprocal transplant field experiments (tadpole growth and development rates) and skeletochronology (longevity, age at maturity, reproductive lifespan and average lifetime fecundity). On average, high altitude populations of all species had shorter breeding and activity seasons than low altitude populations (up to 10 weeks less in some cases). The magnitude of the difference in breeding season length varied among years depending on the average temperature and rainfall for the year; i.e. differences appeared greater in warmer and wetter years. Within a population males had longer breeding and activity seasons than females. Although breeding season length varied with altitude, the number of nights that individuals were active within the breeding season did not vary; i.e. low altitude populations were not active for more nights despite having a longer breeding season. This result was attributed to the absence of a relationship between individual activity and environmental variables (air temperature, rainfall, etc.) in many of the populations. Generally, intraspecific clutch size did not vary significantly with altitude. This result was due to the absence of a significant relationship between female body size and altitude (as clutch size is proportional to female body size). Egg size also did not vary with altitude however, suggesting egg size may be canalized (i.e. fixed) in these species. Results also suggest that females of these species only produce one clutch of eggs per season. Interspecific differences in reproductive characteristics largely reflected differences in reproductive mode, larval habitat and female body size. Altitude negatively influenced growth and development rates in L. chloris and development rates in L. pearsoniana. Tadpoles raised at high altitudes were also generally larger at each Gosner Development Stage in both species. The results of the reciprocal transplant experiments suggested that most of the variation in growth and development rates was due to environmental factors (water temperature) rather than genetic or maternal factors. Altitude or genetic factors did not significantly affect tadpole survival in either species. The results suggest that tadpoles occurring at high altitudes take longer to reach metamorphosis and do so at a larger size than their lowland counterparts. With the exception of L. lesueuri, skeletochronology was suitable for age estimation in the study species. Altitude had a significant effect on the age at maturity or longevity in some of the species, however there were trends toward older individuals and older ages at maturity in high altitude populations for the remaining species. Females were generally older than males for all species and in the case of longer-lived species (i.e. Mixophyes spp.) also tended to be older when breeding for the first time. The large overlap of body sizes of individuals of different ages demonstrates that body size is a poor indicator of age in these species. This is the first study to estimate average lifetime fecundity for more than one amphibian species and/or population. The results suggest that the absence of significant altitudinal variation in the average lifetime fecundity of different populations is due to tradeoffs made by females (current reproduction vs. survival). There was no significant altitudinal variation in annual survival and recapture rates in any of the species, and generally there was no difference in the survival and recapture rates of males and females in each population. Within a year, monthly survival and recapture rates were more variable at low than high altitudes and this was attributed to the longer breeding season of low altitude populations. The results did not support previous studies that suggested there was a size bias in survival and recapture rates. The shorter breeding seasons, slower growth and development rates, older age at maturity and greater longevity found in the high altitude study populations will result in increased generation time in those populations. In turn, increased generation time can cause high altitude populations to be less resilient (i.e. population takes longer to return to equilibrium after a disturbance away from equilibrium) (Pimm et al. 1988, Pimm 1991) and ultimately more vulnerable or prone to extinction or decline. The majority of unexplained global amphibian declines have occurred at high altitudes in tropical and subtropical areas. These latitudinal patterns may be explained by the narrow range of environmental tolerances exhibited by tropical organisms resulting in mountains being effectively higher in the tropics. Consequently, high altitude tropical species are likely to be even more vulnerable than temperate species occurring at similar altitudes. Further work on the effects of geographic variation, especially interactions between altitude and latitude are needed to evaluate the hypotheses for the causes of these declines and disappearances.

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12

Ribeiro, Ricardo da Silva [UNESP]. "Ecologia alimentar das quatro espécies dominantes da anurofauna de serapilheira em um gradiente altitudinal na ilha de São Sebastião, SP." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/99498.

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Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq)
Estudos sobre ecologia alimentar de taxocenoses neotropicais que incluem a anurofauna são raros, sendo inéditos para a Mata Atlântica. O presente estudo se propôs a realizar a caracterização comparativa, qualitativa e quantitativa das dietas e dos nichos alimentares das quatro espécies de anuros mais abundantes na serapilheira da Ilha de São Sebastião, litoral norte do Estado de São Paulo Brachycephalus sp. (aff. nodoterga), Leptodactylus cf. marmoratus, Eleutherodactylus binotatus e Eleutherodactylus parvus ao longo de um gradiente altitudinal de 0 a 900 m. Essas quatro espécies apresentam diferentes picos de densidade populacional ao longo do gradiente altitudinal, com sobreposição variável de ocorrência em determinadas altitudes, sendo que duas delas B. sp. (aff. nodoterga) e L. cf. marmoratus não coocorrem. Eleutherodactylus parvus revelou-se como predador generalista, apesar dos machos adultos comportarem-se como especialistas em artrópodes pouco quitinizados, e não apresenta mudança ontogenética na dieta. Brachycephalus sp. revelou-se um predador especialista em ácaros mas, ao contrário dos demais anfíbios especialistas em ácaros, rejeita formigas. Devido a isso, é a única espécie de anuro conhecida até o momento que não possui correlação significativa entre suas medidas morfométricas e as de suas presas. Leptodactylus cf. marmoratus apresentou padrões de dieta distintos, sendo especialista em formigas na presença de E. binotatus e especialista em artrópodes pouco quitinizados na ausência deste, que sempre se comportou como especialista em artrópodes pouco quitinizados. Os resultados obtidos contribuem para o melhor conhecimento da ecologia básica de comunidades de anfíbios neotropicais.
Studies on feeding ecology on Neotropical communities including amphibians are rare, being unknown for Atlantic Rainforest. This work deals the comparative, qualitative and quantitative characterization of the diets and the alimentary niches of the four more abundant species of anurans of the leaf-litter of São Sebastião Island, north coast of São Paulo State Brachycephalus sp. (aff. nodoterga), Leptodactylus cf. marmoratus, Eleutherodactylus binotatus, and Eleutherodactylus parvus , along an altitudinal gradient of 0 to 900 m. These four species present different peaks of populational density along altitudinal gradient, with variable overlap in different altitudes, being that two of them B. sp. (aff. nodoterga) e L. cf. marmoratus did not co-occur. Eleutherodactylus parvus behaved as generalist predator, notwithstanding adult males behaved as non-ant specialists predators, and not present ontogenetic changes on the diet. Brachycephalus sp. (aff. nodoterga) was as ant-specialist predator that, nevertheless, refuses ants, eating mainly mites. This is the only anuran species known until now that does not present significant correlation between its morfometric measures and of its preys. Leptodactylus cf. marmoratus presents distinct alimentary patterns when in the presence (ant-specialist) or in the absence (non-ant specialist) of E. binotatus, that is a non-ant specialist predator.

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13

Ramos, Juliana Zina Pereira [UNESP]. "Ecologia e biologia reprodutiva de duas espécies simpátricas do gênero Aplastodiscus na Serra do Japi, município de Jundiaí, Estado de São Paulo." Universidade Estadual Paulista (UNESP), 2006. http://hdl.handle.net/11449/106552.

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Estudos comparativos sobre biologia reprodutiva e interações sociais em espécies simpátricas e taxonomicamente próximas de anuros ainda são escassos, embora estes aspectos tenham fundamental importância não apenas para o estabelecimento das relações filogenéticas entre espécies do mesmo grupo, mas também para a compreensão dos mecanismos que atuam na segregação das espécies no ambiente. O presente estudo foi desenvolvido na Serra do Japi, Município de Jundiaí, um dos últimos remanescentes de Mata Atlântica no Estado de São Paulo, Brasil. Durante os meses de março/04 a janeiro/06 foram coletados dados sobre a biologia reprodutiva, ecologia, repertório acústico e interações sociais de Aplastodiscus arildae e A. leucopygius. Três ambientes foram visitados (lagoa, riacho e brejo), nos quais foram coletadas as seguintes informações: características físicas dos sítios de vocalização e reprodução, temporada de vocalização e reprodução, deslocamento de indivíduos e densidade de espécimes. Quanto ao uso do ambiente, a espécie Aplastodiscus leucopygius foi registrada nos três ambientes estudados, enquanto A. arildae foi observada apenas no riacho. Ambas utilizaram a vegetação marginal ao corpo d água como sítio de vocalização. A espécie A. arildae mostrou-se menos generalista quanto ao uso do ambiente para a reprodução. As duas espécies apresentaram estação reprodutiva prolongada e positivamente relacionada com o regime de chuvas na região. Este fato é muito comum entre espécies de anuros e evidencia a importância da disponibilidade de água para a reprodução. Foram identificados três tipos de canto para cada espécie: canto de anúncio, canto de corte e canto territorial. As funções sociais dos cantos foram estabelecidas de acordo com os contextos sociais em que foram emitidos...
Comparative studies on reproductive biology and social interactions among closely related sympatric species of anurans are still rare. However, these aspects are fundamental, not only for the understanding of taxonomic relationships, but also to access the mechanisms responsible for maintaining segregation of species in the environment. This study was carried out at Serra do Japi, one of the last remnants of Atlantic rainforest, in the Municipality of Jundiaí, State of São Paulo, Brazil, from March/04 to January/06. During this period we collected data about ecology, reproductive biology, acoustic repertoire, and social interactions of Aplastodiscus arildae and A. leucopygius. Three habitats were visited (lake, stream, and swamp), where we collected the following information: characteristics of the calling and reproductive sites, calling and breeding periods, displacement of individuals, and species density. Aplastodiscus leucopygius was registered in the three studied habitats, whereas A. arildae was found only in the stream. Both species used the vegetation at the edge of water bodies as calling sites. Aplastodiscus arildae can be considered less generalist with regard to the habitat used for reproductive activity. Both species showed a prolonged breeding season positively correlated with the rainfall in the area. This fact is very common among anuran species and emphasizes the importance of water for reproduction in species of this group. We identified three different types of call for each species: advertisement call, courtship call, and territorial call. Social functions of the vocalizations were established according to the social context in which they were emitted... (Complete abstract, click electronic access below)

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14

Oliveira, Thiago Alves Lopes de. "Anurofauna em uma área de ecótono entre Cerrado e Floresta Estacional : diversidade, distribuição e a influência de características ambientais /." São José do Rio Preto : [s.n.], 2012. http://hdl.handle.net/11449/87577.

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Orientador: Ricardo Jannini Sawaya
Coorientador: Denise de Cerqueira Rossa-Feres
Banca: Paula Hanna Valdujo
Banca: Cínthia Aguirre Brasileiro
Resumo: Dois dos maiores desafios da ecologia de comunidades são encontrar padrões a respeito dos grupos de espécies que vivem em seus ambientes e entender os processos que produzem os padrões atuais. Nesse sentido, estudos que descrevam as comunidades biológicas, explorando os padrões de distribuição das espécies em diferentes escalas espaciais e temporais e que analisem o que poderia influenciar essa distribuição, são de grande interesse geral e nos fornecem importantes informações das espécies e habitats que conhecemos. Dessa forma, esse trabalho visa compreender a estrutura de uma comunidade de anfíbios anuros em uma área de ecótono entre cerrado e floresta estacional no nordeste do Estado de São Paulo (Estação Ecológica de Jataí - EEJ). Essas fisionomias no Estado de São Paulo sofreram intensamente a ação de fragmentação e perda de habitat, devido principalmente à urbanização, pecuária e cultivo de monoculturas como a cana-de-açúcar. A área de estudo é a maior unidade de conservação do bioma Cerrado no Estado de São Paulo e apresenta uma interessante área de estudo devido à configuração espacial da área, uma transição entre mosaico de fisionomias de Cerrado e Floresta Estacional. O objetivo do trabalho foi descrever a diversidade da anurofauna terrícola e entender os padrões de distribuição de abundâncias das espécies e de coocorrência. Além desses objetivos, e devido ao viés encontrado na maioria dos trabalhos de ecologia de comunidades que avaliam a influência de descritores dos habitats aquáticos sobre a riqueza e abundância de anfíbios anuros, nosso trabalho também visa compreender os efeitos das características dos habitats terrestres sobre a abundância da anurofauna avaliando quais características do meio físico, como cobertura do dossel, porcentagem... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Two of the biggest challenges in community ecology are the capacity to find patterns in groups of species that live in their environment and to understand the processes that produce these patterns. Accordingly, studies describing the biological communities, exploring their species distribution patterns at different spatial and temporal scales and analyzing what factors influence the distribution of species, are of great interest and provide important information of the species and habitats that we know. Thus, this study aims to understand the structure of a community of frogs and toads in an area of ecotone between savanna and semideciduous forest in the northeastern of São Paulo state (Jataí Ecological Station - JEE). These physiognomies in the state of Sao Paulo suffered intense fragmentation and habitat loss, primarily due to urbanization, livestock and cultivation of monocultures as sugarcane. The study area are the largest protected area of Cerrado in São Paulo state, and presents an interesting area of study due to the spatial configuration of transition between a mosaic of Cerrado and a Floresta Estacional. The aim of this study was to describe the diversity of terrestrial frogs and toads and to understand the patterns of species abundance distributions and co-occurrence. Besides these goals, and due to the bias found in most studies of community ecology to assess the influence of descriptors of aquatic habitats on the richness and abundance of amphibians, our work also aims to understand the effects of the features of terrestrial habitats on the frog's abundance examining which features of the physical environment, such as canopy cover, percent cover soil, distance from the nearest body of water, could better predict the abundance of anurans. For this purpose, we installed pitfall traps with drift fences... (Complete abstract click electronic access below)
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15

Vradenburg, John. "Distribution and abundance of anurans in southeast Missouri." Diss., Columbia, Mo. : University of Missouri-Columbia, 2005. http://hdl.handle.net/10355/4258.

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Thesis (M.S.)--University of Missouri-Columbia, 2005.
The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file. Title from title screen of research.pdf file viewed on (January 10, 2007) Includes bibliographical references.

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16

Blazeski, Valerie. "The behavioural responses of anurans to ultraviolet radiation." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk3/ftp04/mq39174.pdf.

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17

Houtman, David B. "A Neural Model of Call-counting in Anurans." Thèse, Université d'Ottawa / University of Ottawa, 2012. http://hdl.handle.net/10393/23392.

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Temporal features in the vocalizations of animals and insects play an important role in a diverse range of species-specific activities such as mate selection, territoriality, and hunting. The neural mechanisms underlying the response to such stimuli remain largely unknown. Two species of anuran amphibian provide a starting point for the investigation of the neurological response to species-specific advertisement calls. Neurons in the anuran midbrain of Rana pipiens and Hyla regilla exhibit an atypical response when presented with a fixed number of advertisement calls. The general response to these calls is mostly inhibitory; only when the correct number of calls is presented at the correct repetition rate will this inhibition be overcome and the neurons reach a spiking threshold. In addition to rate-dependent call-counting, these neurons are sensitive to missed calls: a pause of sufficient duration—the equivalent of two missed calls—effectively resets a neuron to its initial condition. These neurons thus provide a model system for investigating the neural mechanisms underlying call-counting and interval specificity in audition. We present a minimal computational model in which competition between finely-tuned excitatory and inhibitory synaptic currents, combined with a small propagation delay between the two, broadly explains the three key features observed: rate dependence, call counting, and resetting. While limitations in the available data prevent the determination of a single set of parameters, a detailed analysis indicates that these parameters should fall within a certain range of values. Furthermore, while network effects are counter-indicated by the data, the model suggests that recruitment of neurons plays a necessary role in facilitating the excitatory response of counting neurons—although this hypothesis remains untested. Despite these limitations, the model sheds light on the mechanisms underlying the biophysics of counting, and thus provides insight into the neuroethology of amphibians in general.

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18

Ramos, Juliana Zina Pereira. "Ecologia e biologia reprodutiva de duas espécies simpátricas do gênero Aplastodiscus na Serra do Japi, município de Jundiaí, Estado de São Paulo /." Rio Claro : [s.n.], 2006. http://hdl.handle.net/11449/106552.

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Resumo: Estudos comparativos sobre biologia reprodutiva e interações sociais em espécies simpátricas e taxonomicamente próximas de anuros ainda são escassos, embora estes aspectos tenham fundamental importância não apenas para o estabelecimento das relações filogenéticas entre espécies do mesmo grupo, mas também para a compreensão dos mecanismos que atuam na segregação das espécies no ambiente. O presente estudo foi desenvolvido na Serra do Japi, Município de Jundiaí, um dos últimos remanescentes de Mata Atlântica no Estado de São Paulo, Brasil. Durante os meses de março/04 a janeiro/06 foram coletados dados sobre a biologia reprodutiva, ecologia, repertório acústico e interações sociais de Aplastodiscus arildae e A. leucopygius. Três ambientes foram visitados (lagoa, riacho e brejo), nos quais foram coletadas as seguintes informações: características físicas dos sítios de vocalização e reprodução, temporada de vocalização e reprodução, deslocamento de indivíduos e densidade de espécimes. Quanto ao uso do ambiente, a espécie Aplastodiscus leucopygius foi registrada nos três ambientes estudados, enquanto A. arildae foi observada apenas no riacho. Ambas utilizaram a vegetação marginal ao corpo dágua como sítio de vocalização. A espécie A. arildae mostrou-se menos generalista quanto ao uso do ambiente para a reprodução. As duas espécies apresentaram estação reprodutiva prolongada e positivamente relacionada com o regime de chuvas na região. Este fato é muito comum entre espécies de anuros e evidencia a importância da disponibilidade de água para a reprodução. Foram identificados três tipos de canto para cada espécie: canto de anúncio, canto de corte e canto territorial. As funções sociais dos cantos foram estabelecidas de acordo com os contextos sociais em que foram emitidos... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Comparative studies on reproductive biology and social interactions among closely related sympatric species of anurans are still rare. However, these aspects are fundamental, not only for the understanding of taxonomic relationships, but also to access the mechanisms responsible for maintaining segregation of species in the environment. This study was carried out at Serra do Japi, one of the last remnants of Atlantic rainforest, in the Municipality of Jundiaí, State of São Paulo, Brazil, from March/04 to January/06. During this period we collected data about ecology, reproductive biology, acoustic repertoire, and social interactions of Aplastodiscus arildae and A. leucopygius. Three habitats were visited (lake, stream, and swamp), where we collected the following information: characteristics of the calling and reproductive sites, calling and breeding periods, displacement of individuals, and species density. Aplastodiscus leucopygius was registered in the three studied habitats, whereas A. arildae was found only in the stream. Both species used the vegetation at the edge of water bodies as calling sites. Aplastodiscus arildae can be considered less generalist with regard to the habitat used for reproductive activity. Both species showed a prolonged breeding season positively correlated with the rainfall in the area. This fact is very common among anuran species and emphasizes the importance of water for reproduction in species of this group. We identified three different types of call for each species: advertisement call, courtship call, and territorial call. Social functions of the vocalizations were established according to the social context in which they were emitted... (Complete abstract, click electronic access below)
Orientador: Célio Fernando Baptista Haddad
Coorientador: Cynthia Peralta de Almeida Prado
Banca: Ariovaldo Pereira da Cruz Neto
Banca: José Perez Pombal Junior
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19

Ribeiro, Ricardo da Silva. "Ecologia alimentar das quatro espécies dominantes da anurofauna de serapilheira em um gradiente altitudinal na ilha de São Sebastião, SP /." Rio Claro : [s.n.], 2006. http://hdl.handle.net/11449/99498.

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Orientador: Célio Fernando Baptista Haddad
Banca: Ricardo Jannini Sawaya
Banca: Augusto Shinya Abe
Resumo: Estudos sobre ecologia alimentar de taxocenoses neotropicais que incluem a anurofauna são raros, sendo inéditos para a Mata Atlântica. O presente estudo se propôs a realizar a caracterização comparativa, qualitativa e quantitativa das dietas e dos nichos alimentares das quatro espécies de anuros mais abundantes na serapilheira da Ilha de São Sebastião, litoral norte do Estado de São Paulo Brachycephalus sp. (aff. nodoterga), Leptodactylus cf. marmoratus, Eleutherodactylus binotatus e Eleutherodactylus parvus ao longo de um gradiente altitudinal de 0 a 900 m. Essas quatro espécies apresentam diferentes picos de densidade populacional ao longo do gradiente altitudinal, com sobreposição variável de ocorrência em determinadas altitudes, sendo que duas delas B. sp. (aff. nodoterga) e L. cf. marmoratus não coocorrem. Eleutherodactylus parvus revelou-se como predador generalista, apesar dos machos adultos comportarem-se como especialistas em artrópodes pouco quitinizados, e não apresenta mudança ontogenética na dieta. Brachycephalus sp. revelou-se um predador especialista em ácaros mas, ao contrário dos demais anfíbios especialistas em ácaros, rejeita formigas. Devido a isso, é a única espécie de anuro conhecida até o momento que não possui correlação significativa entre suas medidas morfométricas e as de suas presas. Leptodactylus cf. marmoratus apresentou padrões de dieta distintos, sendo especialista em formigas na presença de E. binotatus e especialista em artrópodes pouco quitinizados na ausência deste, que sempre se comportou como especialista em artrópodes pouco quitinizados. Os resultados obtidos contribuem para o melhor conhecimento da ecologia básica de comunidades de anfíbios neotropicais.
Abstract: Studies on feeding ecology on Neotropical communities including amphibians are rare, being unknown for Atlantic Rainforest. This work deals the comparative, qualitative and quantitative characterization of the diets and the alimentary niches of the four more abundant species of anurans of the leaf-litter of São Sebastião Island, north coast of São Paulo State Brachycephalus sp. (aff. nodoterga), Leptodactylus cf. marmoratus, Eleutherodactylus binotatus, and Eleutherodactylus parvus , along an altitudinal gradient of 0 to 900 m. These four species present different peaks of populational density along altitudinal gradient, with variable overlap in different altitudes, being that two of them B. sp. (aff. nodoterga) e L. cf. marmoratus did not co-occur. Eleutherodactylus parvus behaved as generalist predator, notwithstanding adult males behaved as non-ant specialists predators, and not present ontogenetic changes on the diet. Brachycephalus sp. (aff. nodoterga) was as ant-specialist predator that, nevertheless, refuses ants, eating mainly mites. This is the only anuran species known until now that does not present significant correlation between its morfometric measures and of its preys. Leptodactylus cf. marmoratus presents distinct alimentary patterns when in the presence (ant-specialist) or in the absence (non-ant specialist) of E. binotatus, that is a non-ant specialist predator.
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20

Sears, Brittany. "Resistance and tolerance to trematode parasites in larval anurans." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4841.

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Nearly every species on the planet has at least one parasite, which, by definition, incurs a cost in the host. Therefore, organisms must resist parasites - preventing or reducing infections - or tolerate parasites - reducing the costs of infection - in order to maintain their fitness despite the presence of parasites. Here, I investigated: 1) whether parasitic, larval trematodes (cercariae) can detect the least resistant tadpole host species, 2) a hypothetical framework for how host life history impacts the utilization of inflammation and thus, resistance and tolerance, 3) whether a common anesthesia technique used in experimental infections immunocompromises tadpoles, 4) the relationship between tadpole host life history, tolerance, and behavioral resistance to cercarial infection, 5) how tadpole behavior affects trematode infection location, and 6) how host life history impacts trematode infection location and the implications of this for host tolerance. In the first chapter, I investigated whether trematode cercariae could discriminate among several tadpole host species to identify the most susceptible hosts. Cercariae were consistently more attracted to Bufo terrestris tadpoles, which was the most susceptible host species. Other tadpole species varied in attractiveness in an order similar to their susceptibility to infection. Furthermore, there was consistent and significant variation among individual attractiveness and susceptibility within host species. If susceptibility to infection is heritable, chemical cues used by cercariae to identify susceptible hosts could represent a substrate on which natural selection acts, setting up a "Red Queen" arms race between host cues and parasite detection of those cues. In the second chapter, I proposed a framework which outlined the cost-benefit relationship between host life history and immune responses. Because inflammatory immune responses are known to cause self-damage to hosts, anti-inflammatory immune responses should vi be used for long-lived, slowly-developing ("slow-paced") hosts, those infected with relatively less virulent parasites, and/or ongoing but ineffective inflammatory responses. Conversely, the cost of inflammation might be less expensive than the cost of infection among shortlived, rapidly-developing ("fast-paced") hosts, those infected with virulent parasites, and/or those undergoing protracted but ineffective anti-inflammatory immune responses. In the third research chapter, I investigated whether two common anesthesia agents, benzocaine and tricaine mesylate (MS-222), immunocompromise tadpoles. These chemicals are used extensively to study the behavioral resistance of tadpoles to cercariae; if treatment increases infections not only by removing these behaviors but also by suppressing the immune system, behavior might appear artificially effective at preventing trematode infection. I found that neither benzocaine nor MS-222 affected the abundance of circulating white blood cells relative to waterexposed control tadpoles. Furthermore, there was no difference in trematode infection success when tadpoles were anesthetized, allowed to recover from anesthesia, and subsequently experimentally infected. The results of this experiment indicate that benzocaine and MS-222 are both practical, non-immunosuppressive anesthesia agents to use when studying trematode infections in amphibians. In the fourth research chapter, I quantified tadpole hosts' use of behavioral resistance (parasite-induced behaviors) and tolerance of exposure to cercariae. Across seven host species, parasite-induced behaviors were negatively correlated with pace-of-life, with rapidly-developing ("fast-paced") tadpoles exhibiting significantly more behavior than slowly-developing ("slowpaced") tadpoles. The opposite pattern was true of tolerance, where fast-paced species had poorer tolerance of cercarial exposure than slow-paced species. Given that slow-paced species are more likely to be exposed to cercariae because they 1) occur in water more likely to harbor cercariae and 2) have longer developmental times, tolerance to trematode exposure might be an vii evolutionary adaptation that circumvents the costs of behavioral - and, possibly, immunological - resistance to infection. In the fifth research chapter, I investigated whether parasite-induced behaviors were capable of affecting encystment location of trematode cercariae in Hyla femoralis tadpoles and whether the resulting encystment location affected tolerance of infection. Benzocaineanesthetized and control tadpoles had similar infection intensities. However, among benzocaineanesthetized tadpoles, the majority of cercarial infections occurred in tadpoles' heads, but unanesthetized control tadpoles were predominantly tail-infected. Furthermore, the number of head infections were negatively associated with mass change (poor tolerance), whereas the number of tail infections was positively associated with mass change (good tolerance). These results suggest that parasite-induced behavior is not only an important mechanism of resistance to trematodes, as other researchers have described, but also a mechanism of tolerance, whereby tadpoles can prevent the deleterious effects of trematode infection by controlling infection location. The sixth research chapter extends the work of the fifth and investigates whether host life history predicts encystment location of cercariae and whether encystment location affects tolerance of infection. Among seven host species, fast-paced species had significantly more infections in the head and body, whereas slow-paced species had the majority of infections in their tails. Slow-paced species were also less resistant to trematode infections in any body location than fast-paced species. These patterns were partially explained by surface area, with a slow-paced species having more surface area (making them more likely to be contacted and infected by cercariae) and a larger proportion of slow-paced species' surface area was comprised by tail than heady and body. Tail infections were less expensive than head and body infections; slow-paced species were more tolerant of infection and across species, tail infections had no effect on tolerance (mass change) whereas head infections were negatively associated with tolerance. These results suggest that slow-paced tadpoles, which are relatively more likely to viii become infected by cercariae and probably have more evolutionary history with these parasites, have invested in a morphology that improves their tolerance to parasites. The body of work that I have produced demonstrates that variation in resistance and tolerance to trematode parasites is ubiquitous among tadpole hosts. Furthermore, this variation is predictable based on host life history. Because tadpole life history can dramatically impact the likelihood of exposure to cercariae and encounters are necessary for host-parasite selective pressure to occur, life history can predict the adaptations of hosts and parasites. Given amphibians' status as the most rapidly declining taxon on the planet and the ubiquity of emerging infectious diseases for amphibians and other organisms, these findings should inform future research on host- and parasite-mediated mechanisms of disease.

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21

Walker, Matthew P. "Effects of Flood Pulsing and Predation on Larval Anurans." Kent State University / OhioLINK, 2014. http://rave.ohiolink.edu/etdc/view?acc_num=kent1397074483.

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22

Fasola, Emanuele. "Acquisition and inheritance of tolerance to metals in anurans." Doctoral thesis, Universidade de Aveiro, 2017. http://hdl.handle.net/10773/22226.

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Doutoramento em Biologia
Os anfíbios encontram-se em declínio a nível global, sendo a contaminação química um dos principais fatores associados a este declínio. De facto, a exposição de populações de anfíbios a este tipo de perturbações ambientais pode provocar a perda de diversidade genética, devido à diminuição de: 1) aptidão, 2) plasticidade ambiental e 3) eficácia dos mecanismos de tolerância. A contaminação por metais é uma das causas de poluição mais comum no mundo, estando presente em larga escala na Península Ibérica, nomeadamente na Faixa Piritosa Ibérica. Deste modo o estudo dos mecanismos de tolerância a metais, em anfíbios, é relevante, assim como a investigação sobre os mecanismos de hereditariedade desta tolerância. Um dos objetivos do presente trabalho centrou-se no estudo da hereditariedade de tolerância a metais em ovos de Pelophylax perezi. Os resultados obtidos sugerem uma dominância genética incompleta como sendo o mecanismo mais provável de hereditariedade de tolerância a contaminação por metais, em ovos de P. perezi. Estes resultados suportam a hipótese de hereditariedade de tolerância recessiva (ou dominância incompleta). Neste contexto, uma perda de diversidade genética em populações de anfíbios, expostas a contaminação por metais pode ocorrer, mesmo que a fixação de alelos na população seja excluída. De modo a estudar a possibilidade de girinos adquirirem maior tolerância a contaminação por metais, devido à sua exposição histórica a este tipo de contaminação, foram recolhidos girinos de P. perezi em locais contaminados por metais e em locais de referência. Posteriormente, os girinos foram expostos, em laboratório, a um pulso de contaminação intensa por metais. Os girinos oriundos de locais contaminados não mostraram maior tolerância à toxicidade letal de metais comparativamente aos girinos recolhidos em locais de referência. Mais ainda, não revelaram estar sujeitos a um maior stress oxidativo. No entanto, a quantidade de metais no corpo provou a contaminação por metais nos locais historicamente impactados e mostrou que os iões de mercúrio e chumbo são prontamente biodisponíveis para os girinos de P. perezi. Os girinos de locais contaminados apresentaram níveis constitutivos de metalotioneínas, superiores aos medidos nos girinos recolhido os nos locais de referência, o que pode indicar adaptação a contaminação por metais. Por fim, o último objetivo consistiu em avaliar a influência de contaminação química na composição e diversidade do microbioma da pele de populações de P. perezi bem como, identificar a sua sensibilidade a contaminação por efluentes de drenagem ácida. O microbioma da pele dos anfíbios apresenta um papel fundamental na proteção destes organismos a agentes perturbadores ambientais. Os resultados obtidos revelaram que os metais podem influenciar a composição da comunidade microbiana de anfíbios que habitam locais contaminados. Mais ainda, uma concentração elevada de efluente de drenagem mineira inibiu o crescimento da maioria dos isolados de bactérias da pele dos anfíbios. Esta inibição pode sugerir que os anfíbios perdem uma fração importante do seu microbioma e consequentemente, afetar a proteção da sua pele, quando expostos a contaminação por metais, o que pode determinar um aumento da sensibilidade a este tipo de contaminação.
Amphibians are declining globally, chemical contamination being one of the major factors driving this process. As a consequence of exposure to such environmental perturbation, natural population of amphibians may lose their genetic diversity, which may occur due to a decrease in: 1) fitness, 2) environmental plasticity capabilities and 3) tolerance mechanisms efficiency. Metal contamination is one of the most worldwide distributed contamination source, having a great impact in the Iberian Peninsula habitats, especially in the Iberian pyrite belt region. Therefore, is important to explore how tolerance mechanism, toward metal contamination, work in amphibians and how genetically determined tolerance mechanisms are inherited. In this work, these topics were addressed by assessing the inheritance to lethal tolerance to acid mine drainage and copper contamination in eggs of the Perez's frog Pelophylax perezi. Incomplete dominance was found to be the most likely inheritance mechanism of tolerance toward these two chemical stressors in the eggs of P. perezi. The results support the recessive (or incompletely dominant) tolerance inheritance (working-) hypothesis. Thus, the amphibians’ populations impacted by metal contamination can considerably lower their genetic diversity, even if allele fixation was excluded. The possibility of tadpoles, historically exposed to metal contamination, being able to acquire an increased tolerance to metal contamination, comparatively to tadpoles inhabiting reference sites, was also studied. Pelophylax perezi tadpoles, sampled at historically metal impacted mining sites, did not show higher oxidative stress or lethal tolerance comparatively to tadpoles inhabiting reference sites. However, the metal body burden proved metal contamination at the historically metal impacted sites and showed that mercury and lead ions are readily bioavailable for P. perezi tadpoles. Furthermore, tadpoles from metal contaminated sites seem to show higher constitutive levels of metallothioneins, which may suggest adaptation to metal contamination The last objective of this work, was to evaluate the influence, of metal contamination, on the composition and diversity of the P. perezi skin microbiome, and to explore its tolerance to acid mine drainage contamination. Amphibians’ skin microbial community has been shown to help its hosts tolerating infections. Because the increasing research on the important protective role of amphibians’ skin microbiome, its diversity and capacity to tolerate metal contamination was as well investigated. Obtained results showed that metal contamination influences the skin microbial community composition in frogs living at metal impacted sites; furthermore, an intense acid mine drainage concentration can inhibit the growth of almost all the isolated strains. This inhibition suggests that amphibians may lose an important part of their skin microbiome, affecting the protection of their skin, when exposed to metal contamination; which, in turn may lead to an increased sensitivity to metal contamination.

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23

Kimmel, Peter Blair. "The significance of hypovolemia in dehydrational death in anurans." PDXScholar, 1985. https://pdxscholar.library.pdx.edu/open_access_etds/3432.

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The importance of hypovolemia in dehydrational death was assessed in two anuran species. Xenopus laeyis, a species which experiences a significant reduction in circulating plasma volume with dehydration, was used to evaluate the role of sympathetic reflex compensation in hypovolemia. Adrenergic blockade with propranolol or phenoxybenzamine produced no significant reduction in dehydration tolerance in this species, although β-blockade with propranolol appeared to have a minor effect. The role of hypovolemic shock in the terminal circulatory collapse that precedes death in dehydrating anurans was investigated in the toad, Bufo marinus. The activity of lysosomal proteinases (cathepsins) was used as an indicator of the shock state. An assay was developed for the determination of cathepsin activity in toad plasma and was used to demonstrate the presence of proteinases similar in pH dependence to mammalian cathepsins Bl and D. Plasma cathepsin D-type activity increased with dehydration in toads but was not significantly different from the activity in controls or in toads subjected to splanchnic artery occlusion. Toads appear to maintain plasma volume to 20% water loss at the expense of other extracellular fluids. These results do not support the hypothesis that hypovolemia is a direct cause of dehydrational death in anurans.

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24

Dayton, Gage Hart. "Community assembly of xeric-adapted anurans at multiple spatial scales." Texas A&M University, 2005. http://hdl.handle.net/1969.1/3296.

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The distribution and abundance of organisms is influenced by historical, abiotic, and biotic factors. The goal of my dissertation was to determine the distribution of anurans in the Big Bend region of the Chihuahuan Desert and to examine how abiotic and biotic factors shape the composition and structure of anuran communities at multiple spatial scales. My approach relied on extensive field surveys, laboratory and field experiments, and GIS modeling. Results from field surveys and reciprocal transplant studies of tadpoles indicate that abiotic conditions of the breeding site most likely do not play a significant role in causing the segregation of species among individual breeding pools. I used laboratory and mesocosm experiments to test for indirect and direct effects of predators on growth and survival of S. couchii tadpoles. I found that S. couchii tadpoles do not alter their behavior in the presence of predators and are very susceptible to predation. Although tadpoles reared with predators suffered high mortality rates, they metamorphosed significantly faster than tadpoles reared without predators. The reduced time to metamorphose is likely a result of the thinning of intraspecific competitors. Because the primary cause of death for S. couchii tadpoles is desiccation due to pond drying, predators may play an important role in facilitating metamorphosis by decreasing competitors and thus increasing per capita resources, therefore decreasing time to metamorphosis for the surviving tadpoles. At the landscape level anuran distributions seem to be influenced by environmental factors that influence the survival of the adult stage. At the level of the breeding site, microhabitat and abiotic components of the aquatic environment do not seem to play an important role in influencing breeding site use by different species. Rather, it seems likely that predation on tadpoles by predators is important in limiting the distribution of some species and that the fast-developing S. couchii may exclude other species from using sites via oophagy and predation on small tadpoles. My research elucidates the fact that in order to understand factors important in regulating ecological communities it is important to examine both abiotic and biotic factors at multiple spatial scales.

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25

Ferreira, Rodrigio Barbosa. "Ecology, Behavior and Taxonomy of Anurans from Brazil's Atlantic Forest." DigitalCommons@USU, 2015. https://digitalcommons.usu.edu/etd/4466.

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The Atlantic Forest extends mainly along the Atlantic coast of Brazil, but today the native habitat is reduced to 14.5% of its historical range. This biome is among the fifth most important biodiversity hotspots in the world due to the high richness and endemism and also high degree of human-induced habitat modification. Understanding the response of species with differing life-history traits to habitat modification such as forest edges and matrix types helps predict species occurrence across changing landscapes. Previous studies have used amphibians as a biological indicator of habitat quality due to their physiological and morphological constraints. Amphibians are also an excellent taxon model to study antipredator behavior due to their variety of defensive postures, vocalizations, skin secretions and aposematic colors. Brazil has currently 1026 recognized amphibian species, of which 60 species were described in the past five years, mostly from the Atlantic Forest biome. New species are increasingly described with the increase in sampling effort at microhabitats from remote areas. My study aimed to understand frog response to habitat modification and their antipredator behaviors, and also to describe a new frog species. First, I demonstrated that the breeding guild was the most important variable explaining frog response to edge effects and matrix types. Leaf-litter and bromeliad breeders decreased in richness and abundance from the forest interior toward the matrix habitats. Water-body breeders increased in richness toward the matrix and remained relatively stable in abundance across distances. Second, I created a database comprising 224 records of frog antipredator behavior, of which 102 (45%) were collected during our fieldwork, 116 (52%) were compiled from the literature, and six (3%) were reported by colleagues. The 224 records represented 165 species, and included 16 families of anurans. Lastly, I described the first bromeliad-dwelling species among the 96 species of the genus Dendropsophus. The new species was diagnosed by its small size, framed dorsal color pattern, medium-sized vocal sac, and short membrane in the fifth toe. Phylogenetic analysis based on molecular data indicated this new species should not be assigned to any of the currently recognized species groups of Dendropsophus.

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26

Engelkes, Karolin [Verfasser]. "Ecomorphology, biomechanics and ontogeny of the pectoral girdle in anurans (Lissamphibia: Anura) with emphasis on morphological methods / Karolin Engelkes." Hamburg : Staats- und Universitätsbibliothek Hamburg Carl von Ossietzky, 2020. http://d-nb.info/1236695097/34.

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27

Alves, Brygida Carolyne Freire. "Influência antrópica sobre a riqueza e abundância de anfíbios anuros em alagados de um remanescente de Mata Atlântica, Paraíba, Brasil." Universidade Estadual da Paraíba, 2014. http://tede.bc.uepb.edu.br/tede/jspui/handle/tede/2261.

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The Neotropical Region has the highest rates of endemism and species richness of amphibians in the world, but there are many gaps in the evaluation of the structure of assemblages in neotropical environments, mainly in the Atlantic Forest. These environments suffer a gradual process of fragmentation resulting from anthropogenic activity, being characterized as a mosaic of forest patches with different disturbances regimes. In this context, the present study aimed to evaluate the anuran assemblages associated with puddles and flooded areas used as breeding sites in the Biological Reserve Guaribas, assessing the existence of patterns of resource use in along the anthropogenic disturbance and the influence of habitat and environmental variables. The samplings were made during the rainy season and wet season form 2013 and twelve environmental variables corresponding to physicochemical aspects of water and soil, as well as characteristics of the vegetation stratification. The environmental variables that contributed most to the dissimilarity between areas was described by PCA, the patterns in structuring the assemblage of anurans between areas was verified by nMDS, the environment/species matrices were related through analysis for CCA check the influence of these environmental factors on anuran assemblage. The hypotheses to be tested were: (1) there is a strong relationship between habitat structure with the anuran assemblages and (2) the environmental factors the puddles and flooded areas influence the patterns of the assemblages structure in a gradient of anthropic disturbance. Twenty species totaling 289 individuals were recorded. The results corroborate the patterns of distribution and richness of frogs in puddles and flooded areas and showed a strong influence of environmental factors. The variables that better explained the structure of the assemblies were related to vertical stratification of vegetation, litter depth, depth of the water body, pH and water temperature. there was a record of the use of 11 distinct microhabitats for reproductive activity, herbaceous vegetation in water and soil and dry soil were the most used. The widespread use of different microhabitats for several species, distributed in breeding sites, indicate the importance of these habitats for the conservation of local anurans in the Atlantic Forest.
A região Neotropical apresenta os maiores índices de riqueza de espécies e endemismos de anfíbios anuros do mundo, porém muitas são as lacunas quanto à avaliação da estruturação das taxocenoses em ambientes neotropicais, sobretudo na Mata Atlântica. Esses ambientes sofrem com o gradativo processo de fragmentação decorrentes da ação antrópica, sendo caracterizadas como um mosaico de manchas de florestas, com diferentes regimes de distúrbios. Nesse contexto, o presente estudo teve por objetivo avaliar a taxocenose de anuros associada a poças e zonas alagadas, utilizadas como sítios reprodutivos na Reserva Biológica Guaribas, verificando a existência de padrões no uso de recursos em um eixo de perturbação antrópica e a influência das variáveis ambientais e dos habitats estudados. As coletas foram realizadas durante o período chuvoso e de estiagem de 2013 e doze variáveis ambientais correspondentes a aspectos fisicoquímicos da água e do solo, bem como características da estratificação vegetal. As variáveis ambientais que mais contribuíram para a dissimilaridade entre as áreas foram descritas através da PCA, os padrões na estruturação da taxocenose de anuros entre as áreas foram verificados através da técnica de ordenação nMDS, as matrizes ambiente/espécies foram relacionadas através da análise CCA para verificar a influência desses fatores ambientais na taxocenose de anuros. As hipóteses testadas foram: (1) há uma forte relação entre a estrutura do hábitat com as assembleias de anuros e (2) os fatores ambientais das poças e áreas alagadas influenciam nos padrões da estrutura das assembleias em um gradiente de perturbação antrópica. Foram registradas 20 espécies, totalizando 289 indivíduos. Os resultados corroboram com os padrões de distribuição e riqueza de anuros em áreas alagadas e poças e evidenciaram uma forte influência dos fatores ambientais. As variáveis que melhor explicaram a estrutura das assembleias foram estratificação vertical da vegetação, profundidade da serrapilheira, profundidade do corpo d’água, pH e temperatura da água. Foi registrado o uso de 11 microhábitats distintos para atividade reprodutiva, vegetação herbácea na água e no solo e solo seco foram os mais utilizados. O uso generalizado dos diversos microhábitats por várias espécies, distribuídos nos sítios de reprodução, indicam a importância desses ambientes para a conservação da anurofauna local no remanescente de Mata Atlântica.

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Madelaire, Carla Bonetti. "Relação sazonal entre reprodução, imunidade e ocorrência de endoparasitas em anfíbios anuros da Caatinga." Universidade de São Paulo, 2012. http://www.teses.usp.br/teses/disponiveis/41/41135/tde-22012013-152255/.

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A grande maioria das espécies de anfíbios anuros apresenta um padrão de reprodução sazonal, caracterizado nos machos por um pico de andrógenos que desencadeia maturação testicular, bem como manutenção do comportamento sexual. No entanto, os altos níveis de andrógenos podem apresentar um efeito imunossupressor, podendo também aumentar a probabilidade de infecções parasitárias. A Caatinga brasileira é caracterizada por altas temperaturas e chuvas sazonais e imprevisíveis que determinam o padrão reprodutivo e de atividade dos anuros dessa região, algumas espécies como P. diplolister apresentam comportamento de estivação durante a seca, já Rhinella Jimi e R. granulosa permanecem ativos quanto ao forrageamento durante este período. As drásticas variações deste ambiente poderiam acentuar os ajustes fisiológicos apresentados por essas espécies, principalmente para a espécie estivadora. Foram estudadas as inter-relações entre caracteres morfológicos, fisiológicos e parasitológicos dessas três espécies de anuros, em três períodos distintos, (A) durante a temporada reprodutiva, em um período entre dois surtos reprodutivos (período entre chuvas); (B) durante um surto reprodutivo que acompanhou um evento de chuvas e (C) no período da seca. As duas espécies de Rhinella apresentaram evidências de modulações imunológicas de acordo com período, e correlações entre caracteres imunológicos, fisiológicos e número de parasitas. Pleurodema diplolister apresentou padrões imunológicos coerentes com o processo de economia energética durante a estivação, como redução do número de leucócitos totais, com concomitante aumento na contagem de eosinófilos e relação positiva entre intensidade parasitária e contagem total de leucócitos. As três espécies estudadas apresentaram depleção das reservas energéticas durante o período reprodutivo, possivelmente associada à alta demanda energética do comportamento vocal. Também apresentaram padrões similares de maturação testicular, evidenciando que as espécies estudadas possuem um padrão de reprodução oportunista, típico de espécies que ocupam ambientes áridos. As três espécies também apresentaram relação entre parâmetros imunológicos e carga parasitária, no entanto, para esclarecer as relações causais entre esses fatores, são necessários testes adicionais de desafio imunológico, bem como infecção experimental por parasitas
Most part of anurans show a seasonal pattern of reproduction, when males display high levels of androgens associated with testicular development and sexual behavior maintenance. However, high androgens levels also can shows an immunosuppressive effect resulting in increased parasitological disease. The semi-arid Caatinga is an environment characterized by high temperatures and unpredictable seasonal rains that determine the breeding season of anurans. During the dry season, Pleurodema diplolister aestivate borrowed, Rhinella granulose and R. jimi remain foraging. Drastic variation in this environment could increase the physiological adjustments displayed by these species, mainly by P. diplolister. The inter-relation between morphological, physiological and parasitological characters was studied in these three anuran species, in three different periods: (A) dry season, (B) during the rainfall, when males are calling, and (C) in the interval between rainfalls, when males are foraging within the reproductive season. The Rhinella species presented evidences of immunological modulations according to the period and correlations between immunological, physiological parameters and number of parasites. Pleurodema diplolister presented immunological patters consistent with the process of energy economy during aestivation, including total leukocyte reduction, along with eosinophil increase and positive relation between total leukocyte and parasite intensity. The three species presented depletion in energy reserves during the breeding season, possibly associated with the high energy demand of vocal behavior. They also presented a similar pattern of testicular development, indicating that these species present opportunistic reproduction pattern, typical of species that occupy arid environments. The studied species also showed correlations between immunological parameters and parasite load, however, to clarify the causal relation between these parameters, additional immunological challenges and experimental parasite infection are necessary

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29

Brede, Edward G. "Genetic diversity in the widespread anurans, Bufo bufo and Rana temporaria." Thesis, University of Sussex, 2003. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.289235.

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30

Schattauer, Sarah Ann. "Non-Ranid Anurans of the Mio-Pliocene Gray Fossil Site, Tennessee." Digital Commons @ East Tennessee State University, 2012. https://dc.etsu.edu/etd/1454.

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Researchers at the GFS, Washington County, Tennessee through the wet screening of nearly 100%of the sediment excavated at the site, recovered an extensive collection of anuran fossil elements. Until recently, these specimens have not been analyzed. The purpose here is the examination, description, and identification of all non-ranid anuran (frogsand toads) material using the following elements: ilium, urostyle, maxilla, frontoparietal, and last sacral vertebra. Anurans identified include Scaphiopus wardorum(extinct spadefoot toad), Bufo terrestris(southern toad), B. cf. B. marinus(giant neotropical toad), three morphotypes of Hyla(tree frogs), and Pseudacris cf. P. brachyphona(mountain chorus frog). Occurrence of these Anura support a paleoecological environment described as warm, moist, and wooded.

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31

Saenz, Daniel. "Ecological correlates of anuran breeding activity and community structure." Texas A&M University, 2004. http://hdl.handle.net/1969.1/1575.

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Multiple ecological factors can simultaneously affect species activity and community structure. The goal of my dissertation was to examine the effects of abiotic factors, biotic factors, and succession on anuran communities. I took a three pronged approach dividing the study into three major chapters. First I focused on abiotic factors that affect anuran breeding activity. I found that weather, rainfall and temperature affect the breeding activity of each species differently, and species in my study area can be placed into 5 different groups based on their association with weather and season: 1) breed within a predictable season (summer) independent of local weather patterns 2) breed opportunistically within a predictable season (summer) dependent on local rainfall 3) breed opportunistically within a predictable season (winter) dependent on local temperature 4) breed opportunistically dependent on local flood level rainfall events and 5) breed opportunistically year round dependent on local temperature in the winter and local rainfall in the summer. In the second part of the study, I created a simulation model of an anuran community using published life history parameters of the anuran species in my study system. Results of the model suggest colonizing ability is important for species with low fecundity and high susceptibility to predation. These early succession species tend to be constrained from later stages of succession by predators. Species that are resistant to predators are generally poor colonizers and tend to arrive late in succession, but once they colonize a pond they tend to persist and recruit successfully. Finally, I explored biotic mechanisms that might be important in structuring anuran communities. I found that with the exception of Rana sphenocephala, anuran species occupying sites with shorter hydroperiods had higher activity rates and were more susceptible to predation. Rana sphenocephala appeared to be better at escaping predation than the other species despite a relatively high activity rate. Examination of published phylogenies indicates R. sphenocephala is derived from a species group that uses permanent water suggesting that R. sphenocephala has retained many anti-predator defenses inherited from its ancestors, even though the species now exploits sites with low predator densities.

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Lins, Aline Gouveia de Souza. "Biodiversidade de helmintos parasitas de anuros da Reserva Particular do Patrimônio natural (RPPN) Cisalpina, Mato Grosso do Sul, Brasil." Botucatu, 2020. http://hdl.handle.net/11449/192248.

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Orientador: Reinaldo José da Silva
Resumo: Parasitas são organismos fundamentais na ecologia e desempenham papel importante nos ecossistemas e estão incluídos na biodiversidade mundial. No presente trabalho foi descrita a diversidade de helmintos na comunidade de 22 espécies de anuros (Boana raniceps, Chiasmocelis albopunctata, Dendropsophus minutus, Dendropsophus nanus, Dermatonotus muelleri, Elachistocleis bicolor, Leptodactylus chaquensis, Leptodactylus fuscus, Leptodactylus latrans, Leptodactylus mystacinus, Leptodactylus podicipinus, Physalaemus albonotatus, Physalaemus cuvieri, Physalaemus nattereri, Pithecopus azureus, Pseudis platensis, Pseudopaludicola mystacalis, Rhinella diptycha, Scinax fuscomarginatus, Scinax ruber, Scinax similis e Trachycephalus typhonius) provenientes da Reserva Particular do Patrimônio Natural (RPPN) Cisalpina, Brasilândia, Mato Grosso do Sul, Brasil. Foram analisados 794 anuros com um total de 22 espécies hospedeiras pertencentes a seis famílias e a prevalência de anuros parasitados foi de 55,5% (441 indivíduos). Foram recuperados 22.350 helmintos distribuídos em 37 taxa. Este estudo amplia o registro tanto para uma nova localidade quanto para registros de novos hospedeiros (n = 55). Nematoides foram os helmintos que apresentaram maior riqueza (n = 22), seguidos de digenéticos (n = 11), cestoides (n = 2), acantocéfalos e monogenéticos (n =1). A comunidade de helmintos foi composta em sua maioria por espécies generalistas (Aplectana membranosa, Cosmocerca parva, Catadiscus marinholutz... (Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Parasites are fundamental organisms in ecology and play an important role in ecosystems and are included in the world biodiversity. The present study describes the diversity of helminth community of 22 anuran species (Boana raniceps, Chiasmocelis albopunctata, Dendropsophus minutus, Dendorpsophus nanus, Dermatonotus muelleri, Elachistocleis bicolor, Leptodactylus chaquensis, Leptodactylus fuscus, Leptodactylus latrans, Leptodactylus mystacinus, Leptodactylus podicipinus, Physalaemus albonotatus, Physalaemus cuvieri, Physalaemus nattereri, Pithecopus azureus, Pseudis platensis, Pseudopaludicola mystacalis, Rhinella diptycha, Scinax fuscomarginatus, Scinax ruber, Scinax similis e Trachycephalus typhonius) from Reserva Particular do Patrimônio Natural (RPPN) Cisalpina, Brasilândia, Mato Grosso do Sul, Brazil. In total, 794 anurans were analyzed with a total of 22 host species belonging to six families and the prevalence of parasitized anurans was 55.5% (441 individuals). We recovered 22,350 helminths distributed in 37 taxa. This study expands the record for both a new location and for new host records (n = 55). Nematodes were the helminths that showed the highest richness (n = 22), followed by digenetics (n = 11), cestodes (n = 2), acanthocephalans and monogenenean (n = 1). The helminth community was mostly composed of generalist species (Aplectana membranosa, Cosmocerca parva, Catadiscus marinholutzi, Catadiscus propinquus). Many larval forms have been found such as Physalopter... (Complete abstract click electronic access below)
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Cornejo, Dennis Oscar. "LARVAL COMMUNITY STRUCTURE IN FOUR SPECIES OF NON-RIPARIAN SONORAN DESERT ANURANS." Thesis, The University of Arizona, 1985. http://hdl.handle.net/10150/275368.

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Silva, Fernando Rodrigues da. "A importância de fragmentos florestais na diversidade de anfíbios anuros em Icém, Região Noroeste do Estado de São Paulo /." São José do Rio Preto : [s.n.], 2007. http://hdl.handle.net/11449/87610.

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Orientador: Denise de Cerqueira Rossa Feres
Banca: Lilian Casatti
Banca: Marcio Martins
Resumo: A composição da paisagem tem um papel fundamental na estrutura e organização de comunidades. A vegetação da região noroeste do Estado de São Paulo, caracterizada como Floresta Estacional Semidecidual e Savana, se restringe hoje a 4% de sua área original, tendo sido substituída por pastagens, culturas diversas ou áreas urbanas. Desta maneira, o objetivo geral do presente estudo foi verificar a importância dos fragmentos florestais para anuros de área aberta em Icém, região noroeste do Estado de São Paulo, procurando responder as seguintes perguntas: i) fragmentos florestais funcionam como áreas de refúgio para espécies de anuros de área aberta? ii) os padrões de riqueza, abundância e distribuição temporal de anuros em corpos d'água vizinhos a fragmentos florestais diferem dos registrados em corpos d'água distantes dos fragmentos? Além disso, investigamos, ao longo de um ano de amostragens, a dieta de anuros capturados em armadilhas de queda instaladas em três fragmentos florestais. Para isso, foram selecionados quatro fragmentos florestais, distanciados entre si de 1 a 4 km, e os seguintes conjuntos de corpos d'água: a) nove brejos, sendo três localizados no interior, três na borda e três distantes (distância mínima de 200 m) dos fragmentos florestais; b) seis açudes, sendo três vizinhos a fragmentos florestais (distância máxima de 50 m da borda dos fragmentos) e três distantes (distância mínima de 300 m) de qualquer fragmento florestal. Foram registradas 25 espécies de anuros, 12 espécies nas armadilhas instaladas no interior dos fragmentos florestais. Destas, três, Eupemphix nattereri, Leptodactylus podicipinus e Physalaemus cuvieri, apresentaram alta abundância (n > 50 exemplares)...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: Landscape arrangement plays a key role in community structure and composition. The northwestern São Paulo State's vegetation, characterized as Semideciduous Seasonal Forest and Savanna, is restricted to 4% of its original area, having been replaced by grazing, plantations or urban areas. Thus, the present study's aim was to verify forest fragments' importance for open-area anurans in Icem, northwestern São Paulo State, looking for answers to these questions: Do forest fragments work as shelter areas for open-area anurans species? Do patterns of richness, abundance and temporal distribution of anurans in water bodies next to forest fragments differ from those registered in water bodies far from the fragments? Furthermore, we investigated, throughout one year of samples, the diet of anurans captured in pitfalls installed in three forest fragments. In order to do so, four forest fragments, 1 to 4km apart from each other, were selected, together with the following groups of water bodies: a) nine swamps, three located in the interior, three in the edge and three distant (minimum distance of 200m) from the forest fragments; b) six ponds, three of them next to the forest fragments (maximum distance of 50 m from the fragments edge) and three distant (minimum distance 300m). Twenty-five species of anurans were registered, twelve species in pitfalls installed in the interior of the forest fragments. Three of these, Eupemphix nattereri, Leptodactylus podicipinus e Physalaemus cuvieri, showed high abundance (n>50 individuals). In pitfalls, 228 individuals, belonging to 10 anuran species, were captured. The high richness and abundance of specimens captured mean that the forest fragments are important components for anuran communities. Water bodies distant from forest fragment showed higher richness (24 species) than those near the fragments (19 species). The opposite occurred with abundance of species...(Complete abstract click eletronic access below)
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Barreto, Débora Soares. "Influência da estrutura do habitat e da matriz sobre a assembleia de anfíbios em uma paisagem naturalmente fragmentada." Universidade Federal de Mato Grosso, 2014. http://ri.ufmt.br/handle/1/660.

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CAPES
Características do habitat são preditoras da diversidade e distribuição de espécies de anfíbios. Em paisagens fragmentadas, tanto características da mancha de habitat como da matriz circundante podem influenciar na composição das espécies nas manchas. No centro-oeste brasileiro, uma das paisagens que podem ser considerada naturalmente fragmentada para os anfíbios são os campos de murundus. Murundus – montículos de terra que não inundam em meio a campo inundável – podem ser vistos como verdadeiras ilhas ecológicas. O objetivo do presente estudo foi avaliar como a assembleia de anfíbios em campos de murundus é influenciada pela estrutura física do murundu, conectividade e pela matriz circundante. O estudo foi realizado em uma região no norte do Pantanal brasileiro, denominada Pirizal, no município de Nossa Senhora do Livramento, Mato Grosso. Para amostragem de anfíbios foram realizadas três campanhas com a duração de oito dias cada uma. Durante as campanhas, 15 murundus foram amostrados por meio de três pares de armadilhas de interceptação e queda. Para caracterizar a estrutura física do murundu, conectividade e a matriz circundante foram mensurados: perímetro da mancha de gravatá, área de troncos caídos, perímetro da base do termiteiro, altura do murundu, textura do solo, além do número de murundus vizinhos ao amostrado, distância média para os murundus vizinhos e soma dos perímetros dos murundus vizinhos. A influência das variáveis ambientais sobre a riqueza e abundância das espécies de anfíbios foi analisada por meio de regressões lineares múltiplas e a composição, através da Análise de Redundância (RDA). Ao longo do estudo foram registrados 1252 anfíbios, sendo as espécies mais abundantes Leptodactylus fuscus (Leptodactylidae), Pseudopaludicola sp. (Leiuperidae) e Rhinella bergi (Bufonidae). A riqueza e a abundância de anfíbios não foram influenciadas pelas variáveis ambientais. Desse modo, variações na riqueza e na abundância de espécies de anfíbios não podem ser atribuídas nem à estrutura física do murundu, nem à conectividade e matriz circundante. Porém, cerca de 47% da variação da composição de espécies foi explicada por variáveis ambientais, principalmente, relacionada à matriz: soma dos perímetros dos murundus vizinhos. Este descritor refere-se ao padrão geral de cobertura da matriz e seus efeitos refletem o fato de que algumas espécies de anuros estiveram mais associadas a ambientes mais fechados, enquanto outras, a ambientes mais abertos. Leptodactylus elenae e Pseudopaludicola mystacalis, por exemplo, foram mais abundantes em murundus inseridos em matriz com maiores valores de soma dos perímetros dos murundus vizinhos, enquanto Leptodactylus labyrinthicus e Rhinella bergi foram mais abundantes em murundus inseridos em matriz com os menores valores. Os resultados indicam que os anuros são sensíveis a mudanças em ambientes fragmentados, nos quais cada espécie responde às variações de acordo com as suas necessidades e com a disponibilidade de recursos necessários à sua sobrevivência. Além disso, em campos de murundus, as características e integridade da matriz onde os murundus estão inseridos pode ter maior importância sobre a composição de espécies nos murundus do que características estruturais dos próprios murundus.
Habitat characteristics are predictors of the diversity and distribution of amphibian species. In fragmented landscapes, both characteristics of the patchy habitats and of the surrounding matrix might influence the composition of species. In central-western Brazil, earthmound fields can be considered a naturally fragmented landscape for amphibians. Earthmounds – small terrain elevations not subject to floods, although situated in seasonally flooded areas – can be treated as ecological islands. The aim of the present study was to evaluate how the anuran assemblage in earthmound fields is influenced by earthmound physical structure, connectivity and by the surrounding matrix. The study was conducted in the northern portion of the Brazilian Pantanal, in a region called Pirizal, municipality of Nossa Senhora do Livramento, Mato Grosso. Anurans were sampled during three expeditions of eight days each, in a total of 15 earthmounds, by using pitfall traps with drift fences. To characterize the physical structure of the earthmounds was measured: perimeter of patches of terrestrial bromeliads, total area of fallen logs, perimeter of the base of termite mounds, height of the earthmound, and soil texture. To characterize the connectivity and physical structure of the surrounding matrix, for each earthmound was counted the number of neighboring earthmounds, and estimated its mean distance for neighboring earthmounds and the sum of the perimeters of these neighboring mounds. The influence of environmental variables on the richness and abundance of amphibians was analyzed using multiple linear regressions. The influence on species composition was analyzed using the Redundancy Analysis (RDA). A total of 1252 anurans were recorded. Leptodactylus fuscus (Leptodactylidae), Pseudopaludicola sp. (Leiuperidae) and Rhinella bergi (Bufonidae) were the most abundant species. The richness and abundance of amphibians were not influenced by environmental variables. Therefore, local variations in the richness and abundance of amphibian species cannot be attributed neither to the physical structure of the earthmounds, nor to the connectivity and surrounding matrix. However, nearly 47% of the variation in species composition was explained by environmental variables related to the matrix: sum of the perimeters of neighboring mounds. The latter descriptor refers to the vegetation cover pattern of the matrix, and recorded effects reflect the fact that some species of frogs were more associated with forested habitats, while others, to more open habitats. Leptodactylus elenae and Pseudopaludicola mystacalis, for example, were more abundant in earthmounds amidst a matrix presenting a higher sum of perimeters of neighboring mounds, while Leptodactylus labyrinthicus and Rhinella bergi were more abundant in earthmounds amidst a matrix with the lowest values. The results indicate that anurans are sensitive to changes in fragmented environments, in which each species responds to variations according to their needs and also according to the availability of resources necessary for their survival. Moreover, characteristics and integrity of the matrix where earthmounds are inserted may have greater importance to maintain species composition than structural characteristics of the earthmounds themselves.

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Eluvathingal, Lilly M. "An Ecological Study of the Anurans in Tea Plantations in a Biodiversity Hotspot." FIU Digital Commons, 2016. http://digitalcommons.fiu.edu/etd/3029.

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Increasing human population size is increasing the demand for resources like timber, oil, tea, coffee, and other crops. Plantation crops mimic some aspects of native habitats, and there are studies that report the presence of some native anuran biodiversity in plantations. I focused on tea plantations in the Western Ghats-Sri Lanka Biodiversity Hotspot and studied the diversity and health of anurans in different habitats found within a tea cultivation area, near Munnar region in the Western Ghats, India. The landscape includes tea bushes, native evergreen shola forest patches, and eucalyptus forest stands. I reviewed 40 studies comparing amphibian species richness in plantations and primary forests. The age of the plantation, type of plantation, presence in a biodiversity hotspot, number of species in the dominant plantation type, number of species in the paired forest habitat, and latitudinal zone of the study, did not correlate with species richness, but plantations that had periodic harvesting had higher species richness than plantations that practiced clear-cut harvesting. I tested different methods of standard amphibian sampling in the field season 2012 in Munnar, and found that Visual Encounter Surveys (VES) in the shola habitat and Stream Transects (ST) were the most efficient. Using the VES and ST methods, I sampled amphibians in three upland habitats (tea, shola, and eucalyptus) at four different sites, and 150m of stream transects at each site, for two consecutive monsoon seasons. Fourteen species were encountered in both years and the community structure was similar across the years. The community structure at the four sites that was driven by the presence of exclusive species at each site and species composition in streams was similar across the landscape and was driven by the presence of similar species in streams across the four sites. Two hundred and sixteen anurans of 17 species, were tested for the presence of the lethal fungus Batrachochytrium dendrobatidis. The preliminary results from the Polymerase Chain Reactions were negative. My study provides baseline data for anuran diversity, composition, and health in the Munnar region of India and results of this project can be compared with tea plantations around the world.

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Brown, Jenise. "Net Effects of Batrachochytrium dendrobatidis (Bd) and Fungicides on Anurans Across Life Stages." Scholar Commons, 2013. http://scholarcommons.usf.edu/etd/4643.

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Amphibians are declining at alarming rates globally. Multiple factors contribute to these declines, including chemical contaminants and emergent diseases. In recent years, agrochemical use, especially fungicide applications, has increased considerably. Previous studies have demonstrated that these agrochemicals leave application sites and enter wetlands via runoff and have detrimental effects on non-target organisms. For example, exposure to contaminants can have multifarious effects on amphibians, such as reducing their ability to deal with a secondary stressor, such as disease. A pathogen that is found concomitant with chemical contaminants in aquatic systems is Batrachochytrium dendrobatidis (Bd). Bd has decimated amphibian populations worldwide. Susceptibility to this pathogen varies across amphibian life stages, and is greater in adults than larvae. Consequently, it is important to examine the effects of simultaneous and serial Bd and agrochemical exposure throughout amphibian development. I assessed the combined effects of 3 different fungicides and Bd on two amphibian species: Cuban tree frogs (Osteopilus septentrionalis) and grey tree frogs (Hyla versicolor), both simultaneously and across life stages. To elucidate the complexities of these interactions, I conducted two experiments, one in the laboratory and another in outdoor mesocosms. Frogs were exposed to most of the possible combinations of fungicides and Bd as tadpoles and metamorphs. The presence of fungicides during the tadpole stage caused no difference in timing to metamorphosis and therefore no extension of time animals were exposed to the pathogen. Fungicides did not reduce fungal growth; in fact, tadpoles exposed simultaneously to a fungicide and Bd, regardless of the specific fungicide, had increased fungal loads compared to acetone controls. Additionally, animals exposed to both stressors simultaneously had higher mortality compared to controls or any of the stressors singly. Lastly, the fungicide had persistent effects on amphibian health by affecting susceptibility to Bd later in ontogeny. Frogs exposed to any of the three fungicides as a tadpole had higher Bd prevalence, Bd abundance, and Bd-induced mortality when challenged with Bd after metamorphosis, an average of 71 days after their last fungicide exposure. In conclusion, I found no benefits of fungicides for amphibians. In fact, results indicate both immediate and delayed negative effects of exposure to fungicides and Bd. These findings highlight the importance of studying multiple potential contributors to amphibian declines, simultaneously and sequentially, to understand net effects of stressors on amphibian performance.

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Lins, Aline Gouveia de. "Helmintofauna associada a leptodactylus fuscus (Anura Leptodactylidae) em regiões de Cerrado, Pantanal e Caatinga no Brasil /." Botucatu, 2016. http://hdl.handle.net/11449/138033.

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Orientador: Reinaldo José da Silva
Abstract: Species differ in their environmental preferences, leading to processes in the community based in gradient variations that decrease as the distance increases. This process diminishes faster in heterogeneous landscapes, especially in solid areas of bands like South American open diagonally, that is characterized by horizontal stratification environments, presenting a landscape mosaic that extends from the Caatinga to the regions of Chaco, through the Pantanal. The Cerrado, Pantanal and Caatinga are characterized by great diversity of vertebrate anuran species, including the host Leptodactylus fuscus. These regions are inserted in the open diagonal South American. The composition and the relationship between parasite-host infra-populations of helminth species associated with L. fuscus specimens were described in three different regions of Brazil. Amphibians are found in a variety of habitats and exhibit different reproductive and behavioral patterns, considered good models to study parasitology. The study evaluated if there is a decay on the similarity between geographically distant communities and concluded that these two variables are positively associated. This study assessed 155 hosts and found a total of 16 taxa: Aplectana membranosa, Aplectana pintoi, Schankiana formosula, Cosmocerca podicipinus, Oswaldocruzia lopesi, Oxyascaris necopinus, Glypthelmins linguatula, Catadiscus cf. marinholutzi, Physaloptera sp., Physalopteroides sp., Rhabdias sp., metacercariae (Diplostomid... (Complete abstract click electronic access below)
Resumo: As espécies diferem em suas preferências ambientais, isto conduz a processos na comunidade baseados em variações de gradiente que decrescem com o aumento da distância, sobretudo em faixas de áreas contínuas como a diagonal aberta sul-americana, apresentando um mosaico paisagístico que se estende desde a Caatinga até as regiões do Chaco. O Cerrado, Pantanal e Caatinga são caracterizados pela grande diversidade de espécies de vertebrados anuros, incluindo o hospedeiro Leptodactylus fuscus, e estas regiões estão inseridas na diagonal aberta Sul Americana. Foi descrita a composição e a relação entre parasita-hospedeiro de infra-populações das espécies de helmintos associados com espécimes do Leptodactylus fuscus em três regiões diferentes do Brasil. Os anfíbios são encontrados em uma variedade de habitats e exibem diversos padrões reprodutivos e comportamentais, por isso são considerados bons modelos de estudo para a parasitologia. O trabalho avaliou se ha um decaimento na similaridade entre comunidades geograficamente distantes, e concluiu que estas duas variáveis se associam positivamente. Foram avaliados 155 espécimes de hospedeiros totalizando 16 taxas de helmintos, Aplectana membranosa, Aplectana pintoi, Schankiana formosula, Cosmocerca podicipinus, Oswaldocruzia lopesi, Oxyascaris necopinus, Glypthelmins linguatula, Catadiscus cf. marinholutzi, Physaloptera sp., Physalopteroides sp., Rhabdias sp., metacercárias da Família Diplostomidae, nematodas da Família Cosmocercidae, ... (Resumo completo, clicar acesso eletrônico abaixo)
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Chu, Joanne Chen. "The effects of acoustic signals and sex steroids on dopaminergic function in male anurans /." Digital version accessible at:, 1998. http://wwwlib.umi.com/cr/utexas/main.

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Galeano, Sandra P. "Enzootic patterns of infection by Batrachochytrium dendrobatidis in pond breeding anurans in Central America /." Available to subscribers only, 2009. http://proquest.umi.com/pqdweb?did=1885689751&sid=1&Fmt=2&clientId=1509&RQT=309&VName=PQD.

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Galeano, Sandra Patricia. "ENZOOTIC PATTERNS OF INFECTION BY BATRACHOCHYTRIUM DENDROBATIDIS IN POND BREEDING ANURANS IN CENTRAL AMERICA." OpenSIUC, 2009. https://opensiuc.lib.siu.edu/theses/62.

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Batrachochytrium dendrobatidis (Bd) has contributed to population declines and extinction of amphibians worldwide. Disease-caused extinction is rare, but may occur where reservoirs exist or where transmission is independent of host density. Because some species persist after Bd epizootic events, they may act as potential reservoirs of the infection. I studied seasonal and elevational patterns of prevalence and intensity of Bd infection in eight pond-breeding species that persisted after an epizootic event at three low- and three mid-elevation ponds in Central America. I visited each pond three times over the rainy season to sample for Bd and to quantify frog density. I recorded air and water temperature at each pond. I analyzed 1,288 samples and detected Bd in all six ponds and in six of the eight species. Elevation and time affected Bd prevalence (F2,7 = 8.90, p = 0.01) and Bd intensity (F2,8 = 9.09, p = 0.008). Frog density was not correlated with Bd prevalence (F1,7= 4.75, p= 0.06), and temperature did not affect prevalence or intensity of the infection. Bd is enzootic at all 6 sites and six pond-breeding species are reservoirs. The presence of abundant reservoirs at enzootic conditions explains the persistence of Bd in areas where other species declined without showing evidence of recovery. Low intensities of infection explain the survivorship of these reservoir species. I suggest that temperature might not be the principal factor molding Bd dynamics in the humid Neotropical forests, and present evidence that ponds are ecosystems where frogs might clean or reduce their infections

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Araújo, Pablo Goyannes de. "Estudo da Comunidade de anfíbios anuros ao longo de um gradiente altitudinal na Ilha Grande, Angra dos Reis, RJ. Rio de Janeiro 2010." Universidade do Estado do Rio de Janeiro, 2010. http://www.bdtd.uerj.br/tde_busca/arquivo.php?codArquivo=3657.

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Este estudo investigou a variação altitudinal da comunidade de anfíbios anuros em uma montanha de floresta Atlântica da Ilha Grande, avaliando a ocorrência, distribuição, organização e riqueza de anuros nas diferentes altitudes. Estabelecemos seis faixas de altitude para realização do estudo: 150, 300, 450, 600, 750 e 900 metros acima do nível do mar. Utilizamos duas metodologias de amostragem: o método de parcelas grandes (5 x 5 metros) e o método de transecção, entre janeiro de 2008 e março de 2009. Os dados indicaram que na região de Mata Atlântica do Pico do Papagaio ocorre uma considerável riqueza de espécies de anuros, a qual varia dependendo da faixa de altitude ao longo do gradiente altitudinal do morro. Houve em geral uma tendência a um decréscimo da riqueza com aumento da altitude, com exceção da altitude de 900 metros, onde a riqueza teve um aumento quando comparado à faixa altitudinal imediatamente abaixo. Nossos dados mostram ainda que ao longo de todo o gradiente altitudinal do morro, as maiores riquezas de anuros em geral ocorrem nas faixas de altitudes de 150 e 300 metros. Nossos dados indicaram para a região estudada uma considerável densidade de anuros, que além de variar significativamente entre as estações seca e chuvosa, foi influenciada negativamente pela altitude: na medida em que houve um aumento da altitude ocorreu uma correspondente diminuição na densidade geral de anuros da comunidade componente. A anurofauna da região do Pico do Papagaio apresentou uma queda abrupta na abundância a partir dos 450 metros de altitude, com grande dominância, em termos numéricos, de três espécies com desenvolvimento direto. Nossos dados mostraram haver uma variação sazonal na abundância e, nas densidades de anuros na região do Pico do Papagaio. Concluímos que a região de Mata Atlântica do Pico do Papagaio possui uma elevada riqueza de espécies de anuros, a qual varia ao longo do gradiente altitudinal com os maiores valores de riqueza e abundâncias encontradas entre as faixas de 150 e 300 metros, o que pode ser favorecido pela menor inclinação do terreno, pela maior ocorrência de cursos dágua e pela elevada pluviosidade que ocorre nestas faixas altitudinais na Ilha Grande. A considerável similaridade na comunidade componente de anuros entre as altitudes de 150 e 300 pode resultar da similaridade estrutural da vegetação entre estas faixas de altitudes. A região em geral teve uma alta densidade de anuros, que além de variar sazonalmente, foi negativamente influenciada pela altitude. A observada redução na abundância dos anuros a partir dos 450 metros de altitude pareceu favorecer espécies com desenvolvimento direto.
This study aimed to investigate the altitudinal variation of the community of amphibians in a mountain of Atlantic forest of Ilha Grande, evaluating the occurrence, distribution, organization and richness of frogs at different altitudes. We established six tracks of altitude for the study: 150, 300, 450, 600, 750 and 900 meters above sea level. We use two sampling methods: the method of plots (5 x 5 meters) and the method of transection between January 2008 and March 2009. The data indicated that in the Atlantic forest of Pico do Papagaio there is a considerable richness of frog species, which varies depending on the range of altitude along the altitudinal gradient of the hill. There was a general tendency to a decrease in richness with increasing altitude, except for the altitude of 900 meters, where richness has increased compared to the altitudinal range immediately below. Our data also show that throughout the altitudinal gradient of the hill, the highest frog richness in general occur from 150 to 300 meters. Our data indicated that the density of frogs, varied significantly between the dry and rainy seasons, was negatively influenced by altitude: with an increase in altitude there was a corresponding decrease in overall density of anurans. The frogs in the region of Papagaio showed a sharp drop in abundance above 450 meters, with high dominance, in terms of numbers, of three species with direct development. Our data showed a seasonal variation in the abundances and densities of frogs in the region of Pico do Papagaio. We conclude that the Atlantic Forest region of Pico do Papagaio has a high species richness of frogs, which varies along the altitudinal gradient with the greatest richness and abundance found between 150 and 300 meters, which can be favored by the lower slope, the higher occurrence of water courses and the high rainfall that occurs in these altitudinal zones at Ilha Grande. The considerable similarity in the community component of frogs between the altitudes of 150 and 300 can result from the structural similarity of vegetation between these altitudes. The region in general had a high density of frogs, which also vary seasonally, and was negatively influenced by altitude. The observed reduction in abundance of frogs from 450 meters upward seemed to favor species with direct development.

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Chandler, Mark. "The evolutionary ecology of parasitism in relation to recombination in a neotropical community of anurans." Thesis, McGill University, 1993. http://digitool.Library.McGill.CA:80/R/?func=dbin-jump-full&object_id=39826.

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The rate of recombination and parasite load of species of anuran from Peruvian Amazonia were examined to test the idea that recombination functions to diversify progeny in order to resist the continual counter-adaptation of parasites. The anurans were found to be hosts to over 32 species of macroparasite, as well as a wide variety of protistan and moneran parasites. It was found that a combination of three variables (diet, habitat, abundance), together with host body size accounted for a substantial proportion of the variation in mean parasite richness and parasite species distribution among host species. The relationship between parasites and ecology was found to be independent of host phylogeny. The demonstration of substantial environmental heterogeneity in parasitization predicates that a positive relationship between parasite richness and recombination should be found in this case. This prediction was supported by the data: highly parasitized species of anuran had higher rates of recombination. This is the first study to demonstrate a direct positive relationship between recombination (rather than sex) and parasites.

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Luiz, Amom Mendes 1987. "Diversity, distribution and conservation of anurans from coastal plains of São Paulo state, Southeastern Brazil." [s.n.], 2014. http://repositorio.unicamp.br/jspui/handle/REPOSIP/315722.

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Orientador: Ricardo Jannini Sawaya
Texto em português e inglês
Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Biologia
Made available in DSpace on 2018-08-25T04:49:01Z (GMT). No. of bitstreams: 1 Luiz_AmomMendes_M.pdf: 2403224 bytes, checksum: ec7b481911e3e7c360533c1254330aab (MD5) Previous issue date: 2014
Resumo: Indivíduos e espécies não são distribuídos aleatoriamente no espaço. Consequentemente, as metacomunidades formadas por tais organismos também apresentam uma organização espacial. Associado a isso, poucas espécies conseguem se distribuir na maioria dos ambientes possíveis. Portanto, as metacomunidades possuem uma variação em sua composição que pode ser espacialmente organizada, ou seja, existem locais que são mais similares em termos de composição de espécies do que outros. Robert Whittaker nomeou esse fenômeno como o componente beta da diversidade, ou simplesmente, diversidade beta. Entender quais processos geram e mantêm os padrões espaciais da diversidade beta é, portanto, uma questão central em ecologia de comunidades, além de auxiliar na proposição de formas apropriadas de manejo e conservação. O objetivo deste estudo foi descrever padrões de diversidade beta de anfíbios anuros das planícies costeiras do Sudeste do Brasil e investigar os possíveis processos que influenciam os padrões de diversidade detectados. A dissertação está dividida em dois capítulos. No primeiro capítulo, descrevo a diversidade beta de anuros da região de estudo e avalio como esses padrões estão protegidos atualmente, por unidades de conservação. No segundo capítulo, busco entender como múltiplos preditores poderiam estar relacionados com a variação na composição de espécies da região de estudo, dado o embasamento teórico e empírico da potencial influência de tais preditores sobre a diversidade de anuros. Os resultados do primeiro capítulo mostraram que existe um padrão claro de organização espacial na diversidade beta, estruturada em três áreas de forma congruente com a história geomorfológica da região. Os resultados evidenciam ainda, que a atual rede de unidades de conservação inclui padrões de diversidade beta semelhante às áreas não protegidas. No entanto, a representatividade dessas unidades em termos de área (~ 4000 km²) é pequena (11.3%). Os resultados do segundo capítulo demonstram a importância de diferentes preditores, incluindo clima, história geomorfológica e processos espaciais em diferentes escalas, para explicar a variação espacial da composição de espécies de anuros. Dentre esses preditores, as unidades geomorfológicas foram predominantemente importantes para explicar a diversidade beta. No entanto, outros processos que foram também importantes para a estruturação das comunidades, como o gradiente climático presente dentro das unidades geomorfológicas, possivelmente gerados pela estrutura geomorfológica da região e pela presença da Serra do Mar. Nossos resultados podem apresentar implicações práticas relacionadas à escolha de potenciais áreas para a conservação das planícies costeiras do Sudeste brasileiro. Tendo em vista a conservação dos padrões de diversidade beta e de seus processos subjacentes, associado à falta representatividade de em termos de tamanho de áreas protegidas na porção central do litoral paulista, sugerimos que tais áreas sejam priorizadas no planejamento e implementação de novas unidades de conservação
Abstract: Individuals and species are not randomly distributed in space. Hence, the communities composed by these species also show a spatial organization. Moreover, only few species can occur in many of the available environments. Therefore, the communities present a variation in their composition which can be spatially structured, that is, there are sites more similar each other in terms of species composition than other ones. Robert Whittaker named this phenomenon as the beta component of diversity or, simply, the beta diversity. The understanding of which processes generate and maintain beta diversity is a central question of the community ecology, also helping in the proposing and applying proper ways to its conservation and management. The aims of this study were to describe the anuran beta diversity patterns of coastal plains from southeastern Brazil and assess potential processes which influence such patterns. This study comprises two chapters. In the first one, I described aspects of the anuran beta diversity in the study region and evaluated how these patterns are protected in conservation units. In the second one, I seek to understand how multiple predictors could be related with the variation in species composition, given the theoretical and empirical framework on the influence of such predictors upon anuran diversity. The results of the first chapter showed a clear spatial pattern in the variation of species composition divided in three main areas that are congruent with the geomorphological history of the region. Still, we showed that the actual network of protected areas include similar beta diversity patterns to unprotected areas. However, the representativeness of these conservation units defined as the covered area (~ 4000 km²) is very small (11.3%). The results of the second chapter demonstrated the relative importance of distinct predictors, including climate, geomorphological history and spatial scales, to explain the spatial variation of the anuran species composition. The beta diversity is mainly associated with spatial structure of geomorphological units. However, other processes are also important in structuring anuran communities, such as climatic gradients possibly related to the geomorphological structure and the presence of Serra do Mar range and also broad scale processes. Our results have practical implications related to the choice of potential areas to coastal plains conservation in southeastern Brazil. In order to conserve the beta diversity patterns and their related processes, associated to unequal representativeness defined by the size area of protected areas, mainly on the central portions of São Paulo state coast, we suggested these areas as priorities in the planning and implementing of new conservation units
Mestrado
Ecologia
Mestre em Ecologia

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Ceruks, Andre. "Diversity, spatial and temporal distribution of anurans (Amphibia) in the Mantiqueira mountais range, southeastern Brazil." Universidade de Taubaté, 2010. http://www.bdtd.unitau.br/tedesimplificado/tde_busca/arquivo.php?codArquivo=142.

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O presente trabalho pretende contribuir para um maior conhecimento dos anfíbios anuros que ocorrem na Serra da Mantiqueira, no município de Monteiro Lobato,SP. O estudo objetivou inventariar as espécies, caracterizar a riqueza, abundância e diversidade, bem como o uso dos hábitats, e micro-hábitats das espécies de anuros registradas, além de fornecer informações para o gerenciamento e sua conservação, podendo futuramente, ser referência para trabalhos similares. A área de estudo se encontra em região de Mata Atlântica com domínio da Floresta Ombrófila Densa, no município de Monteiro Lobato, bairro da Pedra Branca (220 56S e 450 44W). As atividades de campo foram realizadas quinzenalmente, principalmente no período noturno, totalizando 50 amostragens, entre julho de 2007 e julho de 2009. Foram registradas 34 espécies em 17 gêneros de anfíbios anuros, pertencentes a onze famílias: Bufonidae (n=2), Brachycephalidae (n=4), Centrolenidae (n=1), Craugastoridae (n=1), Cycloramphidae (n=1), Hylidae (n=16), Hylodidae (1 espécie), Leuperidae (n=2), Leptodactylidae (n=4), Microhylidae (n=1), Ranidae (n=1). A riqueza de espécies registrada para área de estudo foi considerada alta e quatro dos sete ambientes amostrados apresentaram alta diversidade de espécies (H). A hipótese que melhor explica esses resultados é que a área de estudo apresenta um gradiente de formações vegetacionais distintas, desde a área aberta, passando pela borda florestal até o interior de mata, possibilitando assim a ocorrência de espécies que usam tanto a floresta como a área aberta, ou para reprodução ou para refúgio. O maior número de espécies, que variou de 17 a 27, ocorreu entre os meses mais quentes e chuvosos do ano, padrão esperado para regiões tropicais sazonais, com influencia da temperatura. A sobreposição quanto ao uso de substrato como sítio de vocalização foi maior entre as espécies cujos machos vocalizaram empoleiradas na vegetação, do que entre os machos das espécies que vocalizaram sobre o solo. Esse resultado deve decorrer do maior número de espécies da família Hylidae registrado no presente estudo (47% dos anuros). Além disso, houve maior sobreposição entre as espécies de área aberta e de borda florestal do que no interior de floresta, resultado esse explicado pela maior riqueza de espécies e menor estratificação vegetal que diminuem a partilha de espaço. A similaridade na composição de espécies do presente estudo foi comparada com 15 localidades do Estado de São Paulo e foram associadas à fisionomia vegetal dominante, distância e altitude das áreas amostradas. Os subgrupos formados na análise de similaridade sugerem que a topografia e o gradiente altitudinal são um fator II primário que aponta as semelhanças na composição de espécies de anuros em conjunto com a distância entre as localidades.
This study aims to contribute to a better knowledge of amphibians that occur in the Mantiqueira mountain range in the city of Monteiro Lobato,SP, Brazil. The study aimed to inventory the species, to characterize the richness, abundance and diversity, as well as the use of habitats and microhabitats of frog species recorded, in addition to providing information for management and conservation, and may eventually be the reference for a similar studies. The area of study is in the Atlantic forest region with dense rain forest in the city of Monteiro Lobato, district of Pedra Branca (220 56S e 450 44W). The field activities were carried out fortnightly, mainly at night, totaling 50 samples, between July 2007 and July 2009. We recorded 34 species in 17 genera of frogs belonging to eleven families: Bufonidae (n = 2), Brachycephalidae (n = 4), Centrolenidae (n = 1), Craugastoridae (n = 1), Cycloramphidae (n = 1), Hylidae (n = 16), Hylodidae (n=1), Leuperidae (n = 2), Leptodactylidae (n = 4), Microhylidae (n = 1), Ranidae (n = 1). The species richness recorded for the study area was considered high and four of the seven study sites had high species diversity (H). The hypothesis that best explains these results is that the study area has a gradient of vegetation formations different from the open area, through the forest edge to the forest interior, allowing the occurrence of species that use both the forest and the area open, or for breeding or refuge. The greatest number of species, ranging from 17 to 27, was among the warmest and rainy months of the year, expected pattern for tropical seasonal regions influenced for the temperature. The overlap in the use of substrate as calling site was greatest among species that vocalized perched on vegetation, than among males of species that on the ground. This result should come from the greater number of species of the family Hylidae recorded in this study (47% of species). Furthermore, there was significant overlap between the species of open area and forest edge than in interior forest, the result explained by the higher species richness and lower bedding plant that reduce the sharing of space. The similarity in species composition of the present study were compared with 15 locations in the State of Sao Paulo and were associated with the dominant vegetation type, distance and altitude of the sampled areas. The subgroups formed on the similarity analysis suggests that topography and altitudinal gradient is a primary factor that points to the similarities in composition of frogs in conjunction with the distance between locations.

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Ogilvy, Victoria. "The influence of carotenoids on fitness related traits in anurans : implications for ex situ conservation." Thesis, University of Manchester, 2011. https://www.research.manchester.ac.uk/portal/en/theses/the-influence-of-carotenoids-on-fitness-related-traits-in-anurans-implications-for-ex-situ-conservation(f1f58dbc-77ba-4a34-9378-886a215191a0).html.

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Amphibians are facing an extinction crisis, and in many cases it has become necessary to conserve species in captivity. Unfortunately, our understanding of the nutritional requirements of amphibians in captivity is currently limited. There have been anecdotal reports that captive bred amphibians have duller skin colouration than wild members of the same species. Many amphibians use carotenoid pigments in skin colouration. Carotenoids are yellow-red pigments synthesised by photosynthetic tissues, however vertebrates cannot synthesise them de novo and rely entirely on dietary sources. Reduced colour in captive bred amphibians could therefore result from limited carotenoid availability in the diet. Limited access to carotenoids could have further negative consequences on health and reproductive success since carotenoids are known to function in the immune, antioxidant and reproductive systems of other vertebrate taxa. The role of carotenoids in amphibian fitness is currently unknown, and the aim of this PhD was to assess the importance of carotenoids to anuran amphibians. Skin colour may be influenced by carotenoid availability, and it was therefore important to establish a suitable method for quantifying skin colour in amphibians. In Chapter 1 I assessed two methods for colour quantification, including digital photography and spectrometry. Neither method was significantly more accurate than the other, however I chose to use photography for my studies for reasons of practicality. In Chapters 2 and 3 I assessed the role of carotenoids in the reproductive systems of wild frogs. I found that carotenoid-based skin colouration was involved in the breeding behaviour of wild Agalychnis moreletii frogs. I found positive assortative mating by colour in that frogs were found mating with individuals with similar carotenoid-based colouration. This assortative mating by colour may be driven by mutual mate choice, or may have evolved to prevent mismatched pairing with a sympatric and phenotypically similar species (A. callidryas). I then analysed the carotenoid composition of eggs produced by wild A. moreletii and Phyllomedusa trinitatis, which are tree frogs with similar reproductive ecology but different egg deposition strategies: Agalychnis moreletii deposits green eggs on the surface of leaves while P. trinitatis wraps pale cream eggs in leaves. The concentration and diversity of carotenoids was significantly higher in A. moreletii than P. trinitatis and potential ecological explanations for this are discussed. In Chapter 4 I investigated carotenoid availability in the diet of captive amphibians by analysing the carotenoid composition of commonly used feeder-invertebrates. I assessed interspecific variation in carotenoid accumulation in three feeder-cricket species (Gryllus bimaculatus, Gryllodes sigillatus and Acheta domesticus), which were all fed one of three diets (wheat-bran, fish-food based diet, fresh fruit and vegetables). All three cricket species were a poor source of carotenoids unless they were gut-loaded on a carotenoid-rich diet. Nutrient retention over a two-day period was poor across species. Finally, there were significant interspecific differences in gut-loading capacity, with G. bimaculatus having the greatest capacity. This study shows that carotenoid availability to captive amphibians will be limited unless they are fed specific feeder invertebrate species, recently gut-loaded on carotenoid-rich foods. In Chapters 5, 6 and 7 I assessed the influence of carotenoids on fitness related traits in captive anurans. I firstly assessed colour degradation in captive-reared A. moreletii frogs and looked at whether skin colour could be improved through increased carotenoid availability in the diet. I found that carotenoid-based skin colour degraded quickly in captivity but could be improved through dietary supplementation with carotenoids, however there was a critical period during post-metamorphic growth for deposition of carotenoids in the skin. Next, I investigated the effect of carotenoids on larval growth and development, and post-metamorphic growth, development, skin colour and reproductive success in captive A. callidryas frogs. I found no direct effect of carotenoids during larval stages, however there were carry-over effects on post-metamorphic growth and skin colour. Increased post-metamorphic carotenoid availability positively influenced growth, skin colour and reproductive success. Similarly to A. moreletii, there was a critical period during post-metamorphic growth for deposition of carotenoids in the skin. Finally, I examined the protective potential of carotenoids in Silurana (Xenopus) tropicalis tadpoles that were exposed to ultraviolet (UV) light. Exposure to UV light significantly reduced tadpole survival and there was no evidence that carotenoids afforded any protection. Nevertheless, in tadpoles that were not exposed to enhanced UV light, carotenoids increased survival. Furthermore, carotenoids had a significantly positive effect on the developmental rate of tadpoles in both UV limited and UV enhanced environments. The studies in this PhD show that carotenoid availability has important consequences on fitness related traits in anuran amphibians, which include effects on growth, skin colour, reproductive success and survival. Carotenoid availability to captive amphibians will, however, be low unless they are provided with feeder invertebrates that have been recently gut-loaded on carotenoid-rich foods. These findings should be considered when recommendations are made on the nutritional requirements of amphibians in captivity as they could significantly improve the fitness of captive-bred individuals, and thus increase the success of ex situ conservation programmes.

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Solano, Florez Liliana. "Diversity, phylogeography and conservation of two groups of anurans of the family Hylidae in Mesoamerica." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/diversity-phylogeography-and-conservation-of-two-groups-of-anurans-of-the-family-hylidae-in-mesoamerica(ff757f14-8031-4882-a93d-77e1a16a6d88).html.

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The amphibian fauna of Mesoamerica is one the most diverse, yet the most endangered in the area, perfectly exemplifying why the region is one of the world biodiversity hotspots. I carried out analyses from three interrelated perspectives: Conservation Genetics, species delimitation and Comparative Phylogeography of two genera of the family Hylidae in most of Mesoamerica: Agalychnis and Dendropsophus. First I performed a species delimitation analysis for the genus Agalychnis, with the specific aim of testing for cryptic diversity within the species A. callidryas, which exhibits wide morphological variation and the uncertainty of whether or not it represents more than one species has not been solved. Secondly, I did a conservation analysis of the genus Agalychnis adopting a comparative approach between endangered and non-endangered species and integrating ecological modelling and genetic information, with the aim of gathering key information for a better management and conservation planning at a regional scale of this genus in particular and Hylid frogs in general. This analysis resulted in the suggestion of short-term alternatives for conservation of critically endangered species and the management of non-endangered species at regional scale. Finally, I applied a comparative phylogeographic analysis between the two genera Agalychnis and Dendropsophus with the general objective of identifying factors and processes underlying species origin and dispersal within Mesoamerica. I proposed hypotheses for the colonization and dispersal of species of these two genera within Mesoamerica, on the basis of genetic data, geographical information, and ecological niche modelling. As part of data gathering for the latter analysis a new country record leading to the considerable extension of the geographical distribution of D. phlebodes is reported.

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Escoriza, Daniel. "Factors regulating the invasion of two Mediterranean anurans. The role of niche conservatism, species interaction and habitat selection." Doctoral thesis, Universitat de Girona, 2015. http://hdl.handle.net/10803/300902.

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Amphibians are a group in worldwide decline. The factors that are causing this decline are not well known, but could be multifactorial, related to the recent expansion of pathogens and habitat disturbance. One of these factors related to the loss of habitat quality is the introduction of alien species. These species can compete with or prey on species of the recipient community, producing deep changes in the structure of these communities. For this reason it is a priority to know which factors act by facilitating the invasion process and which species could be more affected by the presence of this alien species. In Catalonia has become established an alien frog, the painted frog. Introduced in the extreme south of France in the early XXth century, this species has expanded gradually, reaching the Llobregat delta to the south and Llanguedoc to the north. This region is rich in native species of amphibians, some of them endemic, and therefore it is necessary to know how this newcomer species interacts with each of these species. We have used a novel approach when analyzing these interactions, applying the theory of morphospaces. The morphospace is the range of morphological variation observed within a community. This morphology is correlated with the use of a niche, and hence the morphological similarities between the invasive and native species serve as a proxy to assess the functional overlap. These analogies in morphospace were evaluated also in the area of native species and among other species of Discoglossus. The question asked is "Does the invasive species occupy a vacant niche, maintaining a similar morphological gap than that observed in the source assemblage and in the case of other species of the genus Discoglossus?”.
Els amfibis són un grup en declivi a nivell mundial. Els factors que estan causant aquest declivi no són coneguts, però podria ser multifactorial, en relació amb l'expansió recent de certs patògens i les alteracions dels hàbitats. Un d'aquests factors que es relacionen amb la pèrdua de qualitat dels hàbitats és la introducció d'espècies exòtiques. Aquestes espècies poden competir o depredar sobre les espècies de la comunitat recipient, produint profundes alteracions en l'estructura d'aquestes comunitats. Per aquesta raó és prioritari conèixer que factors actuen facilitant el procés invasiu i quines espècies es poden veure més afectades per la presència d'una espècie exòtica. A Catalunya s'ha establert una espècie de anur d'origen africà, la granota pintada. Introduïda a l'extrem sud de França a inicis del segle XX, aquesta espècie s'ha anat expandint de forma progressiva, fins a arribar pel sud al delta del Llobregat i pel nord el Llenguadoc. Aquesta regió és rica en espècies natives d'amfibis, algunes d'elles endèmiques, i per tant cal conèixer com interacciona aquesta espècie recent arribada amb cadascuna d'aquestes espècies. Nosaltres hem utilitzat un enfocament nou en el moment d'analitzar aquestes interaccions, aplicant la teoria dels morfoespais. El morfoespai és el rang de variació morfològica que s'observa dins d'un acoblament. Aquesta morfologia es correlaciona amb l'ús d'un nínxol, i per tant les analogies morfològiques entre l'espècie invasora i les espècies natives poden servir com una aproximació per valorar el solapament funcional. Aquestes analogies en el morfoespai s'han avaluat també en l'area nativa de l'espècie i entre altres espècies de Discoglossus. La pregunta formulada és "ocupa l'espècie invasora un nínxol vacant, mantenint una distància morfològica similar que a l'acoblament d'origen i que altres espècies del gènere Discoglossus?".

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Bowe, Kelsey Lyn. "USE OF ADULT ANURAN COMMUNITIES AND DIETS TO ASSESS THE EFFECTS OF STREAM RESTORATION ON AQUATIC TO TERRESTRIAL FOOD WEB SUBSIDIES." OpenSIUC, 2019. https://opensiuc.lib.siu.edu/theses/2607.

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The boundaries between freshwater and terrestrial ecosystems can be areas of important subsidy transfers. These subsidies, such as leaf litter inputs to streams or aquatic emerging insects into riparian zones, link food webs and provide benefits to consumers in the form of nutrients and energy. Subsidies from aquatic systems tend to have high levels of essential long chain polyunsaturated fatty acids (LC-PUFAs), such as eicosapentaenoic acid (EPA; 20:5n-3) and docosahexaenoic acid (DHA; 22:6n-3) that are only produced by certain forms of aquatic algae. These LC-PUFAs are highly important in growth, development, and other metabolic functions across animal groups (Brett and Muller-Navarra 1997, Gladyshev et al. 2009).

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O'Grady, Richard Terence. "Phylogenetic systematics and the evolutionary history of some intestinal flatworm parasites (Trematoda : Digenea: Plagiorchioidea) of Anurans." Thesis, University of British Columbia, 1987. http://hdl.handle.net/2429/27502.

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Historical structuralism is presented as a research program in evolutionary biology. It uses patterns of common ancestry as initial hypotheses in explaining evolutionary history. Such patterns, represented by phylogenetic trees, or cladograms, are postulates of persistent ancestral traits. These traits are evidence of historical constraints on evolutionary change. Patterns and processes consistent with a cladogram are considered to be consistent with an initial hypothesis of historical constraint. As an application of historical structuralism, a phylogenetic analysis is presented for members of the digenean plagiorchioid genera Glypthelmins Stafford, 1905 and Haplometrana Lucker, 1931. The eight species studied are intestinal parasites of frogs and toads in North, Central, and South America. In a Wagner parsimony analysis of 21 morphological characters with both the PAUP and PHYSYS computer programs, a single phylogenetic tree with a consistency index of 84.8% can be inferred. This suggests strong historical constraint in the evolution of the characters examined. It is postulated that the eight species form a monophyletic group (clade), consisting of two less inclusive clades. Glypthelmins hyloreus and G. pennsylvaniensis comprise one of these clades; G. robustus, G. shastai, H. intestinalis, G. californiensis, G. quieta, and G. facioi comprise the other. G. robustus, found in Bufo marinus in Colombia, is both the southernmost and the most plesiomorphic member of its clade. Glypthelmins californiensis, G. quieta, and G. facioi form a clade, and parasitize frogs in the Rana pipiens complex in Mexico, eastern North America, and Central America, respectively. Glypthelmins shastai and H. intestinalis, the latter of which is the only member of its genus, form a western North American clade, and parasitize Bufo boreas and Rana pretiosa, respectively. The phylogenetic analysis includes a redescription of G. shastai, the synonymy of the genus Haplometrana with Glypthelmins, the redescription of H. intestinali s as G. intestinalis, an emended diagnosis of the genus Glypthelmins, and the first account of the life cycle of G. californiensis. Three aspects of phylogenetic analysis are examined in detail. These are the coding of multistate character trees, the use of parasite data to infer host relationships, and the properties of the Consistency Index and the F-Ratio. It is proposed that the Consistency Index be calculated without non-homoplasious autapomorphic characters. For the present study, this modification gives a value of 76.9%. Using the phylogenetic tree as a general reference system of patterns of common ancestry, it is inferred from developmental studies that (1) there is no conflict between the phylogenetic relationships indicated by only larval or only adult characters, and that (2) the evolution of some of the characters involved certain types of heterochrony. Paedomorphic heterochrony is inferred to have occurred in the evolution of the uterus in G. shastai, H. intestinalis, G. californiensis, G. quieta, and G. facioi. Peramorphic heterochrony is inferred to have occurred in the evolution of the penetration glands in G. facioi, and of the hindbody in H. intestinalis. The relatively longer hindbody of H. intestinalis was experimentally induced to show paedomorphic development by raising specimens of H. intestinalis in Bufo boreas, which is the host of G. shastai, its sister-species. By one year after infection, the relative length of the hindbody is shorter, and is equal to that of the primitive state found in G. shastai. The phylogenetic relationships among the anuran hosts are re-analyzed. There is 80% congruence between them and the postulated phylogenetic tree for their parasites, suggesting strong historical association between the parasite and host groups. This inference of coevolution is further supported by the concordance of the present geographical distributions of the parasites and their hosts with the historical geology of the areas in which they occur. This implies an historical association between the areas and the organisms.
Science, Faculty of
Zoology, Department of
Graduate

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Dissertations / Theses on the topic 'Anurans'

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