Journal articles on the topic 'Whole mammal'
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WATANABE, MASAHITO, and TAKASHI KIHARA. "Carbohydrate distribution in mammal; Whole-body autoradiographic approach." Acta Histochemica et Cytochemica 19, no. 2 (1986): 161–88. http://dx.doi.org/10.1267/ahc.19.161.
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Loggins, Anne A., Ara Monadjem, Laurence M. Kruger, Brian E. Reichert, and Robert A. McCleery. "Vegetation structure shapes small mammal communities in African savannas." Journal of Mammalogy 100, no. 4 (June 7, 2019): 1243–52. http://dx.doi.org/10.1093/jmammal/gyz100.
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Abstract Disturbance by large herbivores, fires, and humans shapes the structure of savannas, altering the amount of woody vegetation and grass. Due to change in the intensity and frequency of these disturbances, savannas are shifting toward grass-dominated or shrub-dominated systems, likely altering animal communities. Small mammals are critical components of savannas, and their distributions likely are affected by these ecosystem-wide changes in vegetative cover. We assessed the responses of small mammals to a gradient of woody cover in low-lying savannas of southeastern Africa. In Kruger National Park (South Africa) and in three nearby reserves (Eswatini), we livetrapped for over 2 years to build multispecies occupancy models that assessed the responses of the small mammal community to grass and woody cover. Overall, whole-community occupancy increased with grass biomass. More species responded positively to woody cover than to grass biomass, but woody cover was associated with reduced occurrence of one species (Mastomys natalensis). Our results suggest that an increase in grass biomass enhances whole-community occupancy of small mammals, but regional diversity is likely to be higher in areas that contain patches of high grass biomass as well as patches of woody cover.
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Jia, Kuntong, Chao Bian, Yunhai Yi, Yanping Li, Peng Jia, Duan Gui, Xiyang Zhang, et al. "Whole Genome Sequencing of Chinese White Dolphin (Sousa chinensis) for High-Throughput Screening of Antihypertensive Peptides." Marine Drugs 17, no. 9 (August 28, 2019): 504. http://dx.doi.org/10.3390/md17090504.
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Chinese white dolphin (Sousa chinensis), also known as the Indo-Pacific humpback dolphin, has been classified as “Vulnerable” on the IUCN Red List of Threatened Species. It is a special cetacean species that lives in tropical and subtropical nearshore waters, with significant differences from other cetaceans. Here, we sequenced and assembled a draft genome of the Chinese white dolphin with a total length of 2.3 Gb and annotation of 18,387 protein-coding genes. Genes from certain expanded families are potentially involved in DNA replication and repairing, suggesting that they may be related to adaptation of this marine mammal to nearshore environments. We also discovered that its historical population had undergone a remarkable bottleneck incident before the Mindel glaciation. In addition, a comparative genomic survey on antihypertensive peptides (AHTPs) among five representative mammals with various residential habitats (such as remarkable differences in exogenous ion concentrations and sea depth) revealed that these small bioactive peptides were highly conserved among these examined mammals, and they had the most abundant hits in collagen subunit proteins, especially for two putative AHTP peptides Gly-Leu-Pro (GLP) and Leu-Gly-Pro (LGP). Our genome assembly will be a valuable resource for further genetic researches on adaptive ecology and conservation biology of cetaceans, and for in-depth investigations into bioactive peptides in aquatic and terrestrial mammals for development of peptide-based drugs to treat various human cardiovascular diseases.
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Hulbert, AJ, and PL Else. "Mammalian metabolism: insights from arid zone reptiles." Australian Mammalogy 26, no. 1 (2004): 111. http://dx.doi.org/10.1071/am04111.
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Mammals, being endotherms have very high metabolic rates compared to ectothermic reptiles. Similarly, small mammals have high rates of mass-specific metabolism compared to larger mammals. This review examines the mechanistic basis of why particular mammal species have a specific metabolic rate. Initial studies compared mammals with arid zone reptile species of the same size and Tb. Mammals have larger internal organs, with more mitochondrial membrane surface area than the reptiles. The cells of mammals are leakier to Na+ ions and their mitochondrial membranes are leakier to H+ ions than in reptile cells. These leakier membranes have membrane lipids that are polyunsaturated and less monounsaturated than their less leaky counterparts. Examination of the cellular basis of allometric variation in metabolism in mammals reveals very similar findings with polyunsaturated membranes associated with the high mass-specific metabolic rates of small mammal species and monounsaturated membranes with low rates of metabolism of large mammals. These findings have resulted in the development of the ?membrane pacemaker? theory of metabolism, which proposes that membrane bilayer composition is regulated in animals and that highly polyunsaturated membranes result in enhanced molecular activity of membrane proteins and in turn this results in an elevated metabolic rate of cells, tissues and consequently whole animals. This theory is also supported by the recent examination of the basis of body-size variation in the metabolic rates of birds. The ?membrane pacemaker? theory of metabolism is currently the only explanation of the mechanisms determining the metabolic rate and thus the cost of living of animals. It has implications for the effect of food habits on metabolism and the relationship between metabolism and lifespan.
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Lacher, Thomas Edward, Shelby D. McCay, Gledson Vigiano Bianconi, Lilianna K. Wolf, Nicolette S. Roach, and Alexandre Reis Percequillo. "Conservation status of the order Rodentia of Brazil: taxonomic and biogeographical patterns." Boletim do Museu Paraense Emílio Goeldi - Ciências Naturais 15, no. 3 (December 21, 2020): 535–56. http://dx.doi.org/10.46357/bcnaturais.v15i3.234.
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The Global Mammal Assessment (GMA) evaluates the risk of extinction for all species of mammals, providing important data on their status to national and global conservation agencies and conventions. We assessed all of the species of Brazilian rodents as part of the GMA activities of the International Union for the Conservation of Nature Species Survival Commission (IUCN SSC) Small Mammal Specialist Group. A total of 234 species were evaluated against the IUCN Red List Criteria and placed into one of eight categories. Although rodents do not have elevated extinction risk compared to mammals as a whole, several families of caviomorph rodents have high levels of either threat, data deficiency, or both. The family Echimyidae has a large number of species and one-third of those either are species of conservation concern or data deficient. The family Ctenomyidae also is of concern in this regard. There are also strong geographic patterns to threat and poor knowledge. The focal areas for conservation effort are the Atlantic Forest and the Cerrado, and for Data Deficient species Atlantic Forest, Cerrado, and Amazonia, in particular the eastern Amazon. The results highlight the need for targeted field research and the application of ecological and spatial data to the development of conservation actions.
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SANTOS-FILHO, Manoel dos, Patrick Ricardo DE LÁZARI, Cícero Pedro Farias de SOUSA, and Gustavo Rodrigues CANALE. "Trap efficiency evaluation for small mammals in the southern Amazon." Acta Amazonica 45, no. 2 (June 2015): 187–94. http://dx.doi.org/10.1590/1809-4392201401953.
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The effectiveness of ecological researches on small mammals strongly depends on trapping techniques to survey communities and populations accurately. The main goal of this study was to assess the efficiency of three types of traps (Sherman, Tomahawk and Pitfall) to capture non-volant small mammals. We installed traps in 22 forest fragments in the southern Brazilian Amazonia. We captured 873 individuals belonging to 21 species; most of the individuals (N = 369) and species (N = 19) were trapped using Pitfalls, followed by Shermans (N = 271 individuals; N = 15 species) and Tomahawks (N = 233 individuals; N = 15 species). Pitfalls trapped a richer community subset of small mammals than the two other types of traps, and a more abundant community subset than Tomahawks. Proechimys sp. was the most abundant species trapped (N = 125) and Tomahawk was the most efficient type of trap to capture this species (N = 97 individuals). Neacomys spinosus and Marmosops bishopi were more trapped in Pitfalls (N = 92 and 100 individuals, respectively) than Shermans and Tomahawks. Monodelphis glirina was more trapped in Shermans and Pitfalls than Tomahawks. Species composition trapped using the three types of traps were distinct. Pitfalls captured a more distinct subset of the small mammal community than the two other live traps. We recommend the association of the three types of traps to reach a more comprehensive sampling of the community of small mammals. Thus, as stated by previous studies, we also recommend the complementary use of Shermans, Tomahawks and Pitfalls to account for a thorough sampling of the whole small mammal community in researches conducted in the tropical forests of Amazonia.
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Boschin, Francesco, Paolo Boscato, Claudio Berto, Jacopo Crezzini, and Annamaria Ronchitelli. "The palaeoecological meaning of macromammal remains from archaeological sites exemplified by the case study of Grotta Paglicci (Upper Palaeolithic, southern Italy)." Quaternary Research 90, no. 3 (November 2018): 470–82. http://dx.doi.org/10.1017/qua.2018.59.
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AbstractBone accumulation in Palaeolithic archaeological sites is often the result of activities carried out by hunter-gatherer groups. Cultural choices may have influenced prey representation in archaeological assemblages, distorting their palaeoecological meaning. We present a comparison between large mammal and small mammal assemblages from the Upper Palaeolithic sequence of Grotta Paglicci (Apulia, southern Italy) that extends from the Marginally Backed Bladelet Aurignacian (about 39,000 cal yr BP) to the Final Epigravettian (about 13,000 cal yr BP). At Paglicci, the high frequency of horse and ibex remains indicates open and dry environments for most of the Upper Palaeolithic. This is confirmed by the predominance of the common vole among small mammals. The alternation between horse and ibex, which takes place during the Upper Palaeolithic, however, looks to be more related to variations in hunting territories. Taxon frequencies change abruptly at 17,955–16,696 cal yr BP, with an increase in woodland-related ungulates together with micromammals, indicating a climatic evolution towards milder and more humid conditions. Results demonstrate that when the association of ungulate taxa is considered as a whole, it has a good palaeoecological signal, whilst considering taxa separately can help to better understand cultural choices of past hunter-gatherer communities.
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Pereira, LG, and L. Geise. "Karyotype composition of some rodents and marsupials from Chapada Diamantina (Bahia, Brasil)." Brazilian Journal of Biology 67, no. 3 (August 2007): 509–18. http://dx.doi.org/10.1590/s1519-69842007000300016.
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The Chapada Diamantina (CD) is located in Bahia State, between 11-14° S and 41-43° W, being part of the Serra do Espinhaço. The occurrence of different habitats and transition areas permits an interesting mammal fauna composition, with species from different biomes living in sympatry. Species of Didelphimorphia and Rodentia are important members of mammal communities in almost all different habitats, and morphological and cytogenetic characters are important for a correct identification of most of these species. In this work 258 specimens of small mammals from the orders Didelphimorphia (six genera and six species) and Rodentia (two families, five Sigmodontinae tribes, nine genera and 11 species) were collected during the whole field work (44 nights with traps). Chromosome preparations were obtained from 145 specimens from the species: Marmosops incanus, Gracilinanus microtarsus, Monodelphis domestica, Akodon aff. cursor, Necromys lasiurus, Cerradomys sp., Oligoryzomys fornesi, O. nigripes, O. rupestris, Calomys expulsus, Rhipidomys macrurus, Wiedomys pyrrhorhinus and Thrichomys inermis. Didelphis albiventris, Micoureus demerarae, Thylamys karymii and Nectomys sp. were identified by morphological characters. Most analyzed specimens do not show karyotype variation. However, numerical chromosomic variation was found in two individuals of Akodon aff. cursor (2n = 15) and in one individual of Cerradomys sp. (2n = 51). Structural variation in karyotype was observed in seven individuals of Cerradomys sp., showing one additional pair of metacentric chromosomes.
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Markham, A. Catherine, Laurence R. Gesquiere, Susan C. Alberts, and Jeanne Altmann. "Optimal group size in a highly social mammal." Proceedings of the National Academy of Sciences 112, no. 48 (October 26, 2015): 14882–87. http://dx.doi.org/10.1073/pnas.1517794112.
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Group size is an important trait of social animals, affecting how individuals allocate time and use space, and influencing both an individual’s fitness and the collective, cooperative behaviors of the group as a whole. Here we tested predictions motivated by the ecological constraints model of group size, examining the effects of group size on ranging patterns and adult female glucocorticoid (stress hormone) concentrations in five social groups of wild baboons (Papio cynocephalus) over an 11-y period. Strikingly, we found evidence that intermediate-sized groups have energetically optimal space-use strategies; both large and small groups experience ranging disadvantages, in contrast to the commonly reported positive linear relationship between group size and home range area and daily travel distance, which depict a disadvantage only in large groups. Specifically, we observed a U-shaped relationship between group size and home range area, average daily distance traveled, evenness of space use within the home range, and glucocorticoid concentrations. We propose that a likely explanation for these U-shaped patterns is that large, socially dominant groups are constrained by within-group competition, whereas small, socially subordinate groups are constrained by between-group competition and predation pressures. Overall, our results provide testable hypotheses for evaluating group-size constraints in other group-living species, in which the costs of intra- and intergroup competition vary as a function of group size.
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An, Xiaopeng, Yue Zhang, Fu Li, Zhanhang Wang, Shaohua Yang, and Binyun Cao. "Whole Transcriptome Analysis: Implication to Estrous Cycle Regulation." Biology 10, no. 6 (May 25, 2021): 464. http://dx.doi.org/10.3390/biology10060464.
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Estrous cycle is one of the placental mammal characteristics after sexual maturity, including estrus stage (ES) and diestrus stage (DS). Estrous cycle is important in female physiology and its disorder may lead to diseases, such as polycystic ovary syndrome, ovarian carcinoma, anxiety, and epilepsy. In the latest years, effects of non-coding RNAs and messenger RNA (mRNA) on estrous cycle have started to arouse much concern, however, a whole transcriptome analysis among non-coding RNAs and mRNA has not been reported. Here, we report a whole transcriptome analysis of goat ovary in estrus and diestrus periods. Estrus synchronization was conducted to induce the estrus phase and on day 32, the goats shifted into the diestrus stage. The ovary RNA of estrus and diestrus stages was respectively collected to perform RNA-sequencing. Then, the circular RNA (circRNA), microRNA (miRNA), long non-coding RNA (lncRNA), and mRNA databases of goat ovary were acquired, and the differential expressions between estrus and diestrus stages were screened to construct circRNA-miRNA-mRNA/lncRNA and lncRNA-miRNA/mRNA networks, thus providing potential pathways that are involved in the regulation of estrous cycle. Differentially expressed mRNAs, such as MMP9, TIMP1, 3BHSD, and PTGIS, and differentially expressed miRNAs that play key roles in the regulation of estrous cycle, such as miR-21-3p, miR-202-3p, and miR-223-3p, were extracted from the network. Our data provided the miRNA, circRNA, lncRNA, and mRNA databases of goat ovary and each differentially expressed profile between ES and DS. Networks among differentially expressed miRNAs, circRNAs, lncRNAs, and mRNAs were constructed to provide valuable resources for the study of estrous cycle and related diseases.
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Dilekova, Olga, Cristina Pavlova, Valentina Shpygova, Nikolai Agarkov, and Vladislav Porublyov. "Dynamics of morphometric parameters of α-endocrinocytes of mammal pancreas." E3S Web of Conferences 175 (2020): 03023. http://dx.doi.org/10.1051/e3sconf/202017503023.
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In domestic animals in postnatal ontogenesis, statistically significant changes in the number of α-endocrinocytes and the values of their nuclear-cytoplasmic ratio in the endocrine islets of pancreas have been revealed, which reflects the species and age-related dynamic processes of its morphofunctional development in animals. In cattle and small cattle (sheep), pigs, dogs and cats, two critical periods of postnatal development of the pancreas have been identified. The first critical period is observed from the birth to the age of three months. It is associated with an alimentary factor: the transition from a dairy diet to roughage, which leads to a decrease in the values of morphometric indicators of the pancreas and the restructuring of the functional work of the organ as a whole. The second critical period is registered in animals during puberty, that is, at 6 months of age, which is associated with the release of hormonal inducers aimed primarily at the implementation of physiological changes in the body.
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Graham, Daniel, Andrea Avena-Koenigsberger, and Bratislav Mišić. "Editorial: Network Communication in the Brain." Network Neuroscience 4, no. 4 (January 2020): 976–79. http://dx.doi.org/10.1162/netn_e_00167.
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Communication models describe the flow of signals among nodes of a network. In neural systems, communication models are increasingly applied to investigate network dynamics across the whole brain, with the ultimate aim to understand how signal flow gives rise to brain function. Communication models range from diffusion-like processes to those related to infectious disease transmission and those inspired by engineered communication systems like the internet. This Focus Feature brings together novel investigations of a diverse range of mechanisms and strategies that could shape communication in mammal whole-brain networks.
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Wright, Traver, Randall W. Davis, Heidi C. Pearson, Michael Murray, and Melinda Sheffield-Moore. "Skeletal muscle thermogenesis enables aquatic life in the smallest marine mammal." Science 373, no. 6551 (July 8, 2021): 223–25. http://dx.doi.org/10.1126/science.abf4557.
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Basal metabolic rate generally scales with body mass in mammals, and variation from predicted levels indicates adaptive metabolic remodeling. As a thermogenic adaptation for living in cool water, sea otters have a basal metabolic rate approximately three times that of the predicted rate; however, the tissue-level source of this hypermetabolism is unknown. Because skeletal muscle is a major determinant of whole-body metabolism, we characterized respiratory capacity and thermogenic leak in sea otter muscle. Compared with that of previously sampled mammals, thermogenic muscle leak capacity was elevated and could account for sea otter hypermetabolism. Muscle respiratory capacity was modestly elevated and reached adult levels in neonates. Premature metabolic development and high leak rate indicate that sea otter muscle metabolism is regulated by thermogenic demand and is the source of basal hypermetabolism.
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Gudova, Marinat, Fatimat Tembotova, Marita Emkuzheva, Albina Amshokova, and Ekaterina Kuchinova. "Current diversity of small mammals of the “Sarykum Barkhans” of Dagestan Reserve." BIO Web of Conferences 35 (2021): 00010. http://dx.doi.org/10.1051/bioconf/20213500010.
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We studied the species diversity and abundance of small terrestrial mammals in the spring and autumn period of 2016-2019 in four groups of habitats of the protected area “Sarykum barkhans” of the Dagestan Nature Reserve: barkhan, floodplain forest, ailant plantations, the territory of the cordon. During the study period, 10 species of terrestrial small mammals were recorded – E. roumanicus, C. suaveolens, C. leucodon, M. musculus, M. macedonicus, A. fulvipectus, C. migratorius, M. socialis, D. sagitta, D. nitedula. Apodemus and Mus mice are the dominant species in the studied area. Mice of Apodemus and M. macedonicus were registered for the first time in the territory of barchans. Indicator species of xerophilic ecosystems – C. migratorius, M. socialis, D. sagitta, were recorded locally, exclusively in the only biotope of barkhan. H. auritus, S. pygmaeus, A. major, M. arvalis, A. terrestris, R. norvegicus, M. tamariscinus, which were previously noted by several authors, were not registered (both traces of vital activity and animals themselves) in the studied area during the whole period of research (2016-2019). Seasonal and annual fluctuations of species diversity and abundance taking into account groups of biotopes and small mammal habitats were revealed.
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Benedek, Ana Maria, Anamaria Lazăr, Niculina Viorica Cic, Maria Denisa Cocîrlea, and Ioan Sîrbu. "Effects of Long-Term Habitat Protection on Montane Small Mammals: Are Sorex araneus and S. minutus More Sensitive Than Previously Considered?" Diversity 14, no. 1 (January 8, 2022): 38. http://dx.doi.org/10.3390/d14010038.
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Protection of natural areas by restricting human activities aims to preserve plant and animal populations and whole communities, ensuring the conservation of biological diversity and enhancement of ecosystem services. Therefore, it is expected that the longer the protection, the stronger the desired effects. We evaluated the responses of small mammals at the population and community levels under protection in the southern Carpathian Mountains. We surveyed small mammals for five years in sites with long- and short-term protection and non-protected. Besides protection status, we included elevation, habitat heterogeneity, and the month of survey as predictors in our models. As response variables, we considered abundance, presence, species composition and species richness. Community abundance responded to all four predictors and species composition was influenced by protection status and month of study. The shrews Sorex araneus and S. minutus had positive responses to protection, both in terms of abundance and relative abundance (their ratio within the community). Our results suggest that overall, montane small mammal communities respond positively to long-term protection, especially S. araneus and S. minutus. These shrew species are considered habitat generalists, but they appear to be in fact sensitive to the habitat quality enhanced through protection.
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Byrom, Andrea E., Ally J. K. Nkwabi, Kristine Metzger, Simon A. R. Mduma, Guy J. Forrester, Wendy A. Ruscoe, Denné N. Reed, John Bukombe, John Mchetto, and A. R. E. Sinclair. "Anthropogenic stressors influence small mammal communities in tropical East African savanna at multiple spatial scales." Wildlife Research 42, no. 2 (2015): 119. http://dx.doi.org/10.1071/wr14223.
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Context Protection of natural ecosystems undoubtedly safeguards ecological communities, with positive benefits for ecosystem processes and function. However, ecosystems are under threat from anthropogenic stressors that reduce the resilience both of component species and the system as a whole. Aims To determine how anthropogenic stressors (land use and climate change) could impact the diversity and resilience of a small mammal community in the greater Serengeti ecosystem, an East African savanna comprising Serengeti National Park (SNP) and adjacent agro-ecosystems, at local (SNP) and Africa-wide geographic scales. Methods We recorded small mammal species in 10 habitats in the greater Serengeti ecosystem, including the agro-ecosystem, over 48 years (1962–2010). We calculated richness and diversity for each habitat type, and used an index of similarity to quantify differences in the community among habitats. Species accumulation curves were also generated for each habitat type. Key results We recorded 40 species of small mammals in the greater Serengeti ecosystem. At the local scale, restricted habitat types in SNP (each <1% of the total area) made a disproportionately large contribution to diversity. Agro-ecosystems had lower richness and were less likely to contain specialist species. At regional and Africa-wide scales, local endemics were less likely to be recorded in the agro-ecosystem (57% species loss) compared with those with regional (33% loss) or Africa-wide (31%) geographic distributions. Conclusions At the local scale, the variety of habitats in SNP contributed to overall diversity. However, the ability to maintain this diversity in the adjacent agro-ecosystem was compromised for localised endemics compared with species with Africa-wide ranges. Land use intensification adjacent to SNP and projected changes in rainfall patterns for East Africa under global climate scenarios may compromise the future resilience of the small mammal community in this tropical savanna ecosystem. Implications The loss of rare or specialised species from protected areas and human-modified ecosystems could be mitigated by: (1) increasing habitat complexity and maintaining specialist habitats in the agro-ecosystem; and (2) creating buffers at the boundary of protected natural ecosystems that accommodate regime shifts in response to climatic change. These measures would increase the resilience of this coupled human–natural savanna ecosystem.
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Guppy, M., S. D. Bradshaw, B. Fergusson, I. A. Hansen, and C. Atwood. "Metabolism in lizards: low lactate turnover and advantages of heterothermy." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 253, no. 1 (July 1, 1987): R77—R82. http://dx.doi.org/10.1152/ajpregu.1987.253.1.r77.
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The bobtail lizard (Tiliqua rugosa) encounters environmental temperatures that range from 7 to 40 degrees C. We have studied the effects of temperature on the whole-body turnover of glucose, lactate, and fatty acid. At 35 degrees C turnover rates of glucose and fatty acid account for the majority of O2 uptake and reflect the low metabolic rate of the bobtail compared with that of a mammal of equivalent mass. Lactate turnover at rest is very low. The low rates of lactate production correlate with a lack, or relative lack, of those tissues that normally produce most of the lactate in a resting mammal, such as nonnucleated red blood cells, renal medulla, and smooth muscle associated with blood vessels. Q10 (change in rate with a 10 degrees C change in temperature) values for turnover rates of glucose and fatty acid increase as temperature decreases. It is concluded that there is an inverse temperature effect that minimizes fuel usage during torpor.
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Bano-Otalora, Beatriz, Franck Martial, Court Harding, David A. Bechtold, Annette E. Allen, Timothy M. Brown, Mino D. C. Belle, and Robert J. Lucas. "Bright daytime light enhances circadian amplitude in a diurnal mammal." Proceedings of the National Academy of Sciences 118, no. 22 (May 24, 2021): e2100094118. http://dx.doi.org/10.1073/pnas.2100094118.
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Mammalian circadian rhythms are orchestrated by a master pacemaker in the hypothalamic suprachiasmatic nuclei (SCN), which receives information about the 24 h light–dark cycle from the retina. The accepted function of this light signal is to reset circadian phase in order to ensure appropriate synchronization with the celestial day. Here, we ask whether light also impacts another key property of the circadian oscillation, its amplitude. To this end, we measured circadian rhythms in behavioral activity, body temperature, and SCN electrophysiological activity in the diurnal murid rodent Rhabdomys pumilio following stable entrainment to 12:12 light–dark cycles at four different daytime intensities (ranging from 18 to 1,900 lx melanopic equivalent daylight illuminance). R. pumilio showed strongly diurnal activity and body temperature rhythms in all conditions, but measures of rhythm robustness were positively correlated with daytime irradiance under both entrainment and subsequent free run. Whole-cell and extracellular recordings of electrophysiological activity in ex vivo SCN revealed substantial differences in electrophysiological activity between dim and bright light conditions. At lower daytime irradiance, daytime peaks in SCN spontaneous firing rate and membrane depolarization were substantially depressed, leading to an overall marked reduction in the amplitude of circadian rhythms in spontaneous activity. Our data reveal a previously unappreciated impact of daytime light intensity on SCN physiology and the amplitude of circadian rhythms and highlight the potential importance of daytime light exposure for circadian health.
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Luchnikova, Ekaterina, Vadim Ilyashenko, Natalya Teplova, Alexander Kovalevsky, and Kirill Zubko. "Impact of agrocenoses on the populations of small mammals of recreational pine forests in the Tom River Valley." E3S Web of Conferences 175 (2020): 14002. http://dx.doi.org/10.1051/e3sconf/202017514002.
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The paper is devoted to studying the influence of agricultural land on the formation of small mammal communities in the pine forests of the Tom River Valley. For the analysis, we took sites of natural and artificial pine forests of different areas experiencing various anthropogenic pressures. It was revealed that species composition, species richness and species diversity of small mammalian communities depend on a whole complex of factors. Thus, the population of right-bank forests is largely determined by the influence of mountain-taiga complexes of mammals in the adjacent territories. Cutting down taiga forests and using the vacant spaces for agricultural purposes lead to the introduction of species that prefer open biotopes to the initial community. A correlation was found between the size of the pine forest and its resistance to invasive species. The creation of artificial pine forests in the forest-steppe does not lead to the formation of typical forest communities of small mammals, due to their limited ability to resettle. Quite extensive, but to varying degrees isolated natural and artificial pine forests within the city and along the boundaries of the city are unique ecological “islands” that play a significant role in maintaining the diversity of the urban fauna ofmammals.
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Hao, Yan, and Daniel Graham. "Creative destruction: Sparse activity emerges on the mammal connectome under a simulated communication strategy with collisions and redundancy." Network Neuroscience 4, no. 4 (January 2020): 1055–71. http://dx.doi.org/10.1162/netn_a_00165.
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Signal interactions in brain network communication have been little studied. We describe how nonlinear collision rules on simulated mammal brain networks can result in sparse activity dynamics characteristic of mammalian neural systems. We tested the effects of collisions in “information spreading” (IS) routing models and in standard random walk (RW) routing models. Simulations employed synchronous agents on tracer-based mesoscale mammal connectomes at a range of signal loads. We find that RW models have high average activity that increases with load. Activity in RW models is also densely distributed over nodes: a substantial fraction is highly active in a given time window, and this fraction increases with load. Surprisingly, while IS models make many more attempts to pass signals, they show lower net activity due to collisions compared to RW, and activity in IS increases little as function of load. Activity in IS also shows greater sparseness than RW, and sparseness decreases slowly with load. Results hold on two networks of the monkey cortex and one of the mouse whole-brain. We also find evidence that activity is lower and more sparse for empirical networks compared to degree-matched randomized networks under IS, suggesting that brain network topology supports IS-like routing strategies.
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Driessen, Michael M., Peter J. Jarman, Micah Visoiu, and Elise Dewar. "Mammal responses to moderate-intensity planned burning in a small, isolated woodland reserve." Wildlife Research 48, no. 6 (2021): 561. http://dx.doi.org/10.1071/wr20165.
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Abstract ContextFire management advice for fauna conservation in protected areas must often be based on expert opinion and extrapolation from very few scientific studies. More monitoring and research are needed to better inform land managers tasked with both managing for biodiversity and managing the threat of bushfires. AimsTo document changes in the activity of native and introduced mammal species in response to planned burns in a small, isolated woodland reserve in Tasmania. MethodsOver a 10-year period, mammal activity was monitored before and after two separate moderate-intensity planned burns in 20-ha management blocks and in unburnt blocks of similar size by using live-trapping and camera-trapping. Vegetation density was monitored concurrently, and we also searched burnt areas for animals killed by fire. Key resultsThe activity of most mammal populations was largely unaffected by the two planned burns. However, during one of the burns, over 20 rufous-bellied pademelons were directly killed as a result of a need to conduct a backburn. The population recovered after 3 years. The activity of red-necked wallabies, common brushtail possums and short-beaked echidnas generally increased across the whole study area during the 10-year monitoring period. Limited evidence suggests that eastern barred bandicoot and European rabbit activity increased after fire. No swamp rat activity was recorded in burnt areas following the planned burns. Unexpectedly they did not recolonise burnt areas and also ceased to be active in control areas for the last 3 years of the study; we hypothesise that this may be due to the increased dryness and thinning of vegetation. ConclusionsWe found that most of the mammal populations within this small, isolated reserve were resilient to the planned burning program, with no or limited short-term effect for all but one species. The absence of swamp rats from burnt or unburnt areas for the last 3 years of our study suggests that factors other than fire are also affecting this species. ImplicationsPlanned burning is an important tool for biodiversity conservation, but its use needs to be underpinned by empirical data because mammal fire responses are likely to be site-, time- and context-specific.
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Menzel, Viviana A., M. Carolina Cassará, Roland Benz, Vito De Pinto, Angela Messina, Vincenzo Cunsolo, Rosaria Saletti, Klaus-Dieter Hinsch, and Elvira Hinsch. "Molecular and functional characterization of VDAC2 purified from mammal spermatozoa." Bioscience Reports 29, no. 6 (July 22, 2009): 351–62. http://dx.doi.org/10.1042/bsr20080123.
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VDAC (voltage-dependent anion channel) is the pore-forming protein located in the outer mitochondrial membrane. In higher eukaryotes, three genes encode VDAC. Nevertheless, the knowledge of VDAC isoforms is mainly restricted to VDAC1, the only isoform that has been characterized from living tissues to date. We have highly enriched the isoform VDAC2 using as starting material bovine spermatozoa. VDAC2 was obtained in the hydroxyapatite/celite pass-through of sperm proteins solubilized with Triton X-100. This fraction showed in SDS/PAGE two major bands and one faint band in the molecular mass range of 30–35 kDa. Two-dimensional electrophoresis resolved these bands in ten spots with various Coomassie Blue staining intensities. Western-blot analysis with antibodies monospecific for each isoform and MS peptide sequencing showed that the main protein resolved in electrophoresis was VDAC2 with minor contaminations of the other isoforms. Proteomic analysis of the higher molecular mass VDAC2 protein allowed the coverage of the whole protein with the exception of the tripeptide A24AR26. In the same material, the presence of two possible amino acid substitutions (T88 to L88 and A97 to Q97) was revealed. Reconstitution of VDAC2 pores in planar lipid bilayers showed typical features of mitochondrial porins. Stepwise increases in membrane conductance were observed with a predominant conductance of approx. 3.5 nS (nanoSiemens) in 1 M KCl. Very often, small short-lived fluctuations were observed with single-channel conductance of approx. 1.5 nS. Bovine spermatozoa VDAC2 was anion selective and showed voltage dependence. The present study is the first work to report the purification and characterization of VDAC2 from a mammalian tissue.
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Woinarski, J. C. Z., C. Palmer, A. Fisher, K. Brennan, R. Southgate, and P. Masters. "Distributional patterning of mammals on the Wessel and English Company Islands, Arnhem Land, Northern Territory, Australia." Australian Journal of Zoology 47, no. 1 (1999): 87. http://dx.doi.org/10.1071/zo99004.
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Eighteen non-marine mammal species (including seven species of bats) were recorded from a total of 49 islands in the Wessel and English Company island chains off north-eastern Arnhem Land, Northern Territory. Most individual species were restricted to, or had higher incidence on, larger islands, and species richness as a whole increased as island size increased. The most notable exception was the semi-aquatic Hydromys chrysogaster, which occurred relatively equitably across island sizes; this species, two bat species and the macropod Petrogale brachyotis were recorded from islands smaller than 10 ha. However, the variation between islands in the number of native terrestrial mammal species was not best predicted by island size, but rather by a combination of sampling effort and altitude (which explained 64% of the deviance in species richness), or altitude and distance to larger land mass (explaining 63% of deviance). Richness–area patterns for individual islands in these chains were reasonably consistent with those of other islands sampled in northern Australia. However, the fauna of the Wessel and English Company groups as a whole was less rich than that of the Pellew and Kimberley islands, and individual islands appeared to have lower species richness than comparable mainland areas. Species that were notably absent or that were recorded from relatively few islands include large macropods, Tachyglossus aculeatus, Antechinus bellus, Phascogale tapoatafa, Sminthopsis spp., Mesembriomys gouldii, Rattus colletti, Leggadina lakedownensis and Pseudomys calabyi. Some of these species may be absent through lack of suitable habitat; others have presumably disappeared since isolation, possibly due to Aboriginal hunting. Richness at the quadrat (50 × 50 m) scale was generally very low. Habitat relationships are described for the 7 species recorded from more than 5 quadrats. At a quadrat-scale, the richness of native mammals was greater on islands larger than 1000 ha than on islands smaller than 1000 ha. Quadrat-scale species richness varied significantly among the islands sampled by the most quadrats (even when the comparison was restricted to either of the two most extensive vegetation types), but this variation was not closely related to either area or altitude. The two most frequently recorded species, the rodents Melomys burtoni and Zyzomys argurus, showed distinct habitat segregation on islands where both were present, but tended to expand their habitat range on islands where only one of the species occurred. The most notable conservation feature of the mammal fauna of the Wessel and English Company Islands is the occurrence of the golden bandicoot, Isoodon auratus, a vulnerable species apparently now extinct on the Northern Territory mainland. Four feral animal species (Rattus rattus, Canis familiaris, Bubalus bubalis and Capra hircus) were recorded from a total of 6 islands.
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Full, R. J., R. Blickhan, and L. H. Ting. "Leg design in hexapedal runners." Journal of Experimental Biology 158, no. 1 (July 1, 1991): 369–90. http://dx.doi.org/10.1242/jeb.158.1.369.
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Many-legged animals, such as crabs and cockroaches, utilize whole-body mechanics similar to that observed for running bipeds and trotting quadrupedal mammals. Despite the diversity in morphology, two legs in a quadrupedal mammal, three legs in an insect and four legs in a crab can function in the same way as one leg of a biped during ground contact. To explain how diverse leg designs can result in common whole-body dynamics, we used a miniature force platform to measure the ground reaction forces produced by individual legs of the cockroach Blaberus discoidalis. Hexapedal runners were not like quadrupeds with an additional set of legs. In trotting quadrupedal mammals each leg develops a similar ground reaction force pattern that sums to produce the whole-body pattern. At a constant average velocity, each leg pair of the cockroach was characterized by a unique ground reaction force pattern. The first leg decelerated the center of mass in the horizontal direction, whereas the third leg was used to accelerate the body. The second leg did both, much like legs in bipedal runners and quadrupedal trotters. Vertical force peaks for each leg were equal in magnitude. In general, peak ground reaction force vectors minimized joint moments and muscle forces by being oriented towards the coxal joints, which articulate with the body. Locomotion with a sprawled posture does not necessarily result in large moments around joints. Calculations on B. discoidalis showed that deviations from the minimum moments may be explained by considering the minimization of the summed muscle forces in more than one leg. Production of horizontal forces that account for most of the mechanical energy generated during locomotion can actually reduce total muscle force by directing the ground reaction forces through the leg joints. Whole-body dynamics common to two-, four-, six- and eight-legged runners is produced in six-legged runners by three pairs of legs that differ in orientation with respect to the body, generate unique ground reaction force patterns, but combine to function in the same way as one leg of a biped.
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HANUM, CUT MAILA, MA’RIFATIN ZAHRAH, MALAHAYATI DAUD, and ROZZA TRI KWATRINA. "Mammals’ abundance in Lingga Isaq Hunting Park Landscape, Aceh." Jurnal Natural 22, no. 3 (October 31, 2022): 148–55. http://dx.doi.org/10.24815/jn.v22i3.27067.
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Hunting-park is a conservation area with the unique attraction of periodically hunting in terms of wildlife management. Lingga Isaq Hunting-Park (LIHP) is one of 13 hunting parks in Indonesia. However, the utilization of LIHP as a hunting park is still facing obstacles; two of which are conflicts of interest among authorities and no data of the animals, especially mammals – the most hunted creatures in the park. Therefore, a study was conducted to identify the mammalian abundance and distribution. This data would be usefull as essential decision-making for hunting-tourist attractions in LIHP. This study used the transect method, with 12 transect strips evenly distributed in those four function areas; three per each. We found 11 species of mammalian that belonging to 8 families. The protected forest had the highest biodiversity value (H’=1.50), while other use areas had the lowest biodiversity value (H’=1.16). Macaca fascicularis had the highest abundance (23 individu), while Sus scrofa was the most evenly distributed mammal in the whole landscape. Protected forests and other utilization areas have the highest habitat similarity, identified as having intense anthropogenic activities. The protected forest also has habitat similarity with hunting-park as both areas are legally protected. Nevertheless, there are only Cervus unicolor, Muntiacus muntjak, and Sus scrofa that are highly recommended for hunting tourism attractions.
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Gheerbrant, Emmanuel, Jean Sudre, Henri Cappetta, Cécile Mourer-Chauviré, Estelle Bourdon, Mohamed Iarochene, Mbarek Amaghzaz, and Baâdi Bouya. "The mammal localities of Grand Daoui Quarries, Ouled Abdoun Basin, Morocco, Ypresian : A first survey." Bulletin de la Société Géologique de France 174, no. 3 (May 1, 2003): 279–93. http://dx.doi.org/10.2113/174.3.279.
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Abstract The unexpected discovery of mammals such as the earliest known proboscidean Phosphatherium escuilliei in the Ouled Abdoun phosphate Basin (Morocco), which is otherwise renowned for its very rich marine vertebrate fauna, has opened major new perspectives on the early African placental fauna. It was the impetus for several field parties by us between 1997 and 2001 which has allowed this survey of the geological, stratigraphic and paleontological context of Phosphatherium localities. This is the first important paleontological field work dealing with higher vertebrates in the Ouled Abdoun Basin since the work of C. Arambourg. Most of the material of Phosphatherium and other Ouled Abdoun mammals was found by local people searching for fossils for dealing, in an area where the economy is widely dominated by the mining development, in addition to more traditional but very poor agricultural resources. All Phosphatherium remains were found in the northeasternmost quarries of the Ouled Abdoun Basin, from a restricted quarrying area called Grand Daoui (fig. 3). In all Grand Daoui recognized localities (8), the mammals come from the lowermost Eocene level. The stratigraphically re-situated mammalian material was found in a bone-bed of the level called “Intercalaire Couches II/I” which is dated as early(iest) Ypresian on the basis of its relative stratigraphic position and its selachian fauna. At present, the occurrence of several mammal horizons in the “Intercalaire Couches II/I” (and Couche I ?) cannot be excluded, but their age difference seems not significant according to both the associated selachian taxa and the mammalian material, in present data. The bone-bed is very rich in macro-vertebrates. It includes especially large teeth of the shark Otodus obliquus which are the subject of very active research for dealing, and which explains the recent discovery of mammals such as Phosphatherium The level “Intercalaire Couches II/I” is made of a hardened phosphatic bioclastic limestone which is separated from underlying Paleocene levels by a major discontinuity. It is the first deposit of the Eocene sequence (megasequence C) in the Ouled Abdoun phosphate series. Deposition of this new sequence partly reworked the underlying Thanetian levels in the lowermost horizons of the level “Intercalaire Couches II/I”, such as the mammals bearing bone-bed. This explains the recovery of Thanetian selachians in the matrix of the holotype of P. escuilliei and its initial allocation to the Thanetian by Gheerbrant et al. [1996, 1998]. These Thanetian selachian species are now clearly recognized as reworked. Studies of new samples of selachians associated with the newly recovered remains of P. escuilliei and other Grand Daoui mammals have confirmed our field observations owing to the identification of typical early Ypresian species which are listed in table I. P. escuilliei and other mammals from Grand Daoui quarries are confidently dated here as early(iest) Ypresian. As a general rule, there is no known concentration of fossil remains of species of terrestrial origin in the Ouled Abdoun epicontinental Basin. The mammals are exceedingly rare, documented by very few occurrences in contrast to the associated very rich marine vertebrate remains in the phosphate deposits. The occurrence of several rare mammals in these marine facies is related to a peculiar taphonomy characterized by a transport from near shores and continental hinterland under conditions of low hydrodynamic energy such as floated bodies. This is consistent with both the scattered nature of the material in the basin and with its well preserved state (e.g., dental rows, skulls) with respect to other early African mammal localities such as the Ouarzazate basin sites. Up to now, the Grand Daoui sites have yielded 7 species of mammals, which is not an inconsiderable diversity. The provisional faunal list includes a new hyaenodontid creodont, a small (P. escuilliei) and a large (Daouitherium rebouli) proboscidean, the two “condylarths” Abdounodus hamdii (cf. Mioclaneidae) and Ocepeia daouiensis (cf. Phenacodonta), and two indeterminate species which are described here. One of these, known only by a broken bilophodont lower molar, might belong to a new “condylarth” or a new ungulate. It has a reduced one-rooted M/3. An isolated M/3 belongs to another new species close to the genus Seggeurius. It is the oldest known hyracoidean along with an indeterminate species from the Ypresian of N’Tagourt 2 (Morocco). In the mammalian Ouled Abdoun « fauna », P. escuilliei is largely predominant. As a whole this “fauna” shows typical endemic African affinities. It provides new insight into the origin and initial radiation of major endemic African placental taxa. Despite their scarcity, the well preserved Ouled Abdoun mammal remains provide new data especially on the earliest known African ungulates. This is indeed the only known locality bearing large mammals in the Paleocene and early Eocene of Africa, probably in connection to the peculiar taphonomy of continental vertebrates in the phosphatic facies. The vertebrates associated with the Grand Daoui mammals include selachians, osteichthyans, marine reptiles (crocodilians, turtles, and the snakes Palaeophis) and also marine birds which are here reported for the first time in the Ouled Abdoun and other African phosphate basins. The Ouled Abdoun birds are diversified and much less rare than the mammals. They are the oldest known birds in Africa and among the oldest representatives of modern marine groups. Preliminary identifications indicate the occurrence of Procellariiformes (cf. Diomedeidae, cf. Procellariidae), Pelecaniformes (cf. Phaethontidae, cf. Prophaethontidae, cf. Fregatidae, cf. Pelagornithidae), and Anseriformes (cf. Presbyornithidae).
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Dotta, Graziela, and Luciano M. Verdade. "Trophic categories in a mammal assemblage: diversity in an agricultural landscape." Biota Neotropica 7, no. 2 (2007): 287–92. http://dx.doi.org/10.1590/s1676-06032007000200031.
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Mammals play an important role in the maintenance and regeneration of tropical forests since they have essential ecological functions and can be considered key-species in structuring biological communities. In landscapes with elevated anthropogenic pressure and high degree of fragmentation, species display distinct behavioral responses, generally related to dietary habits. The landscape of Passa-Cinco river basin, in the central-eastern region of São Paulo State, shows a high degree of anthropogenic disturbance, with sugar cane plantations, eucalyptus forests, native semideciduous forest remnants and pastures as the key habitat types in the region. We surveyed medium to large mammals in those habitats and determined species richness and relative abundance for each of the following trophic categories: Insectivore/Omnivores, Frugivore/Omnivores, Carnivores, Frugivore/Herbivores and Herbivore/Grazers. Differences in species richness and relative abundance among habitats were tested using one-way analysis of variance, followed by Tukey test, considering 1) each of the trophic categories individually and 2) the set of categories together. Between July 2003 and June 2004, 284.4 km were walked and 22 species were recorded (20 native and two exotics). Analysis of variance did not detect differences in species richness for any of the trophic categories or for the assemblage. Considering relative abundance, the analysis detected significant differences only for the whole assemblage, with the assemblage being more abundant in sugar cane plantations compared to pastures. Our results indicate that the heterogeneous landscape of the study area is dominated by generalist species adapted to use different habitat types and food items.
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Heatubun, Fabianus Sebastian. "Gelak-Tawa sebagai Sinyal Transendensi Manusia." MELINTAS 30, no. 3 (July 22, 2015): 346. http://dx.doi.org/10.26593/mel.v30i3.1450.346-359.
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Comic dimension, on the one hand, is a human condition. It is a basic precondition for a human being called to be <em>humanum</em>, to be authentic, complete and true human being. ‘Comic’ (laughter) can be seen as a cultural product that has become nurtural. On the other hand, essentially comic or laughter is innate by origin. The nature of human can be conceived as a mammal that is able of distinguishing itself from other mammals. Thus human as <em>mangel wesen</em> (incomplete and weak being) by laughter has a capacity to transcend herself or himself, her or his body and whole life. It might even further to be said that that comic dimension has a capability to save humankind. In a mystical sense, when we laugh, we live through our most fundamental life. Laughter makes life more alive. Laughter becomes a sacred moment, for it is a blending event of the human with the divine, and in turn it brings back men and women to their original nature as a human being.<br /><br />
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Turvey, Samuel T., and Nathalie Pettorelli. "Spatial congruence in language and species richness but not threat in the world's top linguistic hotspot." Proceedings of the Royal Society B: Biological Sciences 281, no. 1796 (December 7, 2014): 20141644. http://dx.doi.org/10.1098/rspb.2014.1644.
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Languages share key evolutionary properties with biological species, and global-level spatial congruence in richness and threat is documented between languages and several taxonomic groups. However, there is little understanding of the functional connection between diversification or extinction in languages and species, or the relationship between linguistic and species richness across different spatial scales. New Guinea is the world's most linguistically rich region and contains extremely high biological diversity. We demonstrate significant positive relationships between language and mammal richness in New Guinea across multiple spatial scales, revealing a likely functional relationship over scales at which infra-island diversification may occur. However, correlations are driven by spatial congruence between low levels of language and species richness. Regional biocultural richness may have showed closer congruence before New Guinea's linguistic landscape was altered by Holocene demographic events. In contrast to global studies, we demonstrate a significant negative correlation across New Guinea between areas with high levels of threatened languages and threatened mammals, indicating that landscape-scale threats differ between these groups. Spatial resource prioritization to conserve biodiversity may not benefit threatened languages, and conservation policy must adopt a multi-faceted approach to protect biocultural diversity as a whole.
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Sigler, Mike, Doug DeMaster, Peter Boveng, Michael Cameron, Erin Moreland, Kresimir Williams, and Rick Towler. "Advances in Methods for Marine Mammal and Fish Stock Assessments: Thermal Imagery and CamTrawl." Marine Technology Society Journal 49, no. 2 (March 1, 2015): 99–106. http://dx.doi.org/10.4031/mtsj.49.2.10.
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AbstractNational Oceanic and Atmospheric Administration (NOAA) has adopted an integrated ecosystem research approach to understand climate effects on fish, seabirds, and marine mammals in the Arctic. The integrated ecosystem approach combines traditional oceanography, fisheries, and mammal research techniques to improve scientific understanding of how ecosystems function as a whole. Innovative technologies are being developed to aid in this effort. Two new technologies that NOAA deploys in the Arctic are an advanced thermal imaging technology used to survey ice seal abundance and a high-resolution, nonlethal technology, which integrates cameras and trawls to sample pelagic fishes (CamTrawl). The ice seal surveys relied on thermal imagery to detect warm seal bodies hauled out on cold sea ice. Compared to observer-based surveys, thermal detection surveys require fewer personnel and less postsurvey processing time, can be flown at a higher altitude (reducing disturbance of seals), and yield higher rates of seal detection. The CamTrawl is a self-contained stereo-camera system fitted to the aft end of a trawl at the cod end (i.e., capture bag), which can be left open. By integrating a camera system in the aft portion of a trawl, the CamTrawl concentrates marine organisms and presents this captive group to the cameras without having to recover them for onboard counting, as is done in traditional trawl tows. Compared to traditional survey methods, the CamTrawl more precisely places marine organisms spatially in their environment, which is useful because of small-scale variation in the composition and distribution of fish schools.
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Parchman, A. J. "Whole-body mechanics and gaits in the gray short-tailed opossum Monodelphis domestica: integrating patterns of locomotion in a semi-erect mammal." Journal of Experimental Biology 206, no. 8 (April 15, 2003): 1379–88. http://dx.doi.org/10.1242/jeb.00267.
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D’Andrea, PS, R. Gentile, LS Maroja, FA Fernandes, R. Coura, and R. Cerqueira. "Small mammal populations of an agroecosystem in the Atlantic Forest domain, southeastern Brazil." Brazilian Journal of Biology 67, no. 1 (February 2007): 179–86. http://dx.doi.org/10.1590/s1519-69842007000100025.
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This study reports 2 years of the population dynamics and reproduction of a small mammal community using the removal method. The study was conducted in a rural area of the Atlantic Forest, in Sumidouro, Rio de Janeiro State, Brazil. The population sizes, age structure and reproduction were studied for the four most common species in the study area. The overall diversity was 1.67 and ranged between 0.8 to 1.67. The species richness was 13 considering the whole study. The most abundant species were the rodents Nectomys squamipes (n = 133), Akodon cursor (n = 74), Oligoryzomys nigripes (n = 25) and the marsupials Didelphis aurita (n = 58) and Philander frenatus (n = 50). Seven other rodents were captured once: Necromys lasiurus, Akodon montensis, Sooretamys angouya, Oecomys catherine, Oxymycterus judex, Euryzygomatomys spinosus and Trinomys iheringi. There were higher peaks for diversity and species richness during the winter (dry) months, probably due to higher food availability. The marsupials had a seasonal reproduction with highest population sizes at the end of the rainy seasons. Nectomys squamipes reproduced mostly during rainy periods. Akodon cursor reproduced predominantly in the winter with the highest population peaks occurring during this season. The analysis of the population dynamics of the rodent species indicated that no species behaved as an agricultural pest, probably due to the heterogeneous landscape of high rotativity of vegetable cultivation. Rodent populations were more susceptible to the removal procedure than marsupial ones.
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Antsiferova, Anna A., Marina Yu Kopaeva, Vyacheslav N. Kochkin, Pavel K. Kashkarov, and Mikhail V. Kovalchuk. "Disturbance in Mammalian Cognition Caused by Accumulation of Silver in Brain." Toxics 9, no. 2 (February 3, 2021): 30. http://dx.doi.org/10.3390/toxics9020030.
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The influence of daily prolonged administration of silver nanoparticles on the cognitive functions of a model mammal was studied. The accumulation of silver in the whole brain and the hippocampus, cerebellum, cortex and residual brain tissue of the mouse was investigated by highly precise and representative neutron activation analysis, and histological studies were conducted. Here, we show that long-term memory impairments were caused by the accumulation of silver nanoparticles in the brain and its subregions, such as the hippocampus, cerebellum and cortex, in a step-like manner by disturbance of hippocampal cell integrity. Three different approaches allowed us to observe this phenomenon and discover the reasons it occurred.
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Zitterbart, Daniel P., Heather R. Smith, Michael Flau, Sebastian Richter, Elke Burkhardt, Joe Beland, Louise Bennett, et al. "Scaling the Laws of Thermal Imaging–Based Whale Detection." Journal of Atmospheric and Oceanic Technology 37, no. 5 (May 2020): 807–24. http://dx.doi.org/10.1175/jtech-d-19-0054.1.
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AbstractMarine mammals are under growing pressure as anthropogenic use of the ocean increases. Ship strikes of large whales and loud underwater sound sources including air guns for marine geophysical prospecting and naval midfrequency sonar are criticized for their possible negative effects on marine mammals. Competent authorities regularly require the implementation of mitigation measures, including vessel speed reductions or shutdown of acoustic sources if marine mammals are sighted in sensitive areas or in predefined exclusion zones around a vessel. To ensure successful mitigation, reliable at-sea detection of animals is crucial. To date, ship-based marine mammal observers are the most commonly implemented detection method; however, thermal (IR) imaging–based automatic detection systems have been used in recent years. This study evaluates thermal imaging–based automatic whale detection technology for its use across different oceans. The performance of this technology is characterized with respect to environmental conditions, and an automatic detection algorithm for whale blows is presented. The technology can detect whales in polar, temperate, and subtropical ocean regimes over distances of up to several kilometers and outperforms marine mammal observers in the number of whales detected. These results show that thermal imaging technology can be used to assist in providing protection for marine mammals against ship strike and acoustic impact across the world’s oceans.
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Battistoni, Maria, Renato Bacchetta, Francesca Di Renzo, Francesca Metruccio, Roberta Pennati, and Elena Menegola. "Teratogenic Potential of Traditionally Formulated and Nano-Encapsulated Vitamin A in Two Vertebrate Models, Rattus norvegicus and Xenopus Laevis." International Journal of Food and Nutritional Science 6, no. 1 (May 17, 2019): 43–51. http://dx.doi.org/10.15436/2377-0619.19.2493.
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Nano-encapsulation is applied for the preparation of functional food to preserve micronutrients degradation and to ameliorate their absorption. Being nano-encapsulation already related to increased vitamin A embryotoxicity, we aimed to evaluate the effect of traditionally formulated (BULK-A) and nano-encapsulated vitamin A (NANO-A) in two different vertebrate models: rat post implantation Whole Embryo Culture (WEC) and Frog Embryo Teratogenesis Assay-Xenopus (FETAX). After benchmark-dose modelling, WEC results showed that NANO-A was 7 times more effective than BULK-A, while FETAX results indicated that X. laevis development was affected only by NANO-A. The relative potency of WEC was 14 times the potency of FETAX, suggesting a minor role of preformed vitamin A in X. laevis development in respect to mammal embryogenesis. Results from this work prompt the necessity to monitor the use of food supplemented with NANO A, since even low doses can elicit teratogenic effects on vertebrate embryos due to its increased bioavailability.
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Scherbarth, Frank, Victoria Diedrich, Rebecca A. Dumbell, Herbert A. Schmid, Stephan Steinlechner, and Perry Barrett. "Somatostatin receptor activation is involved in the control of daily torpor in a seasonal mammal." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 309, no. 6 (September 15, 2015): R668—R674. http://dx.doi.org/10.1152/ajpregu.00191.2015.
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Siberian hamsters ( Phodopus sungorus) show spontaneous daily torpor only after ∼2 mo in winter-like short photoperiods (SP). Although some SP-induced hormonal changes have been demonstrated to be necessary for the occurrence of seasonal torpor, the whole set of preconditions is still unknown. Recent findings provide evidence that the hypothalamic pituitary growth axis is involved in endocrine responses to SP exposure in the photoperiodic hamsters. To examine whether suppression of growth hormone (GH) and insulin-like growth factor-1 (IGF-1) secretion affects the incidence of daily torpor, we used two somatostatin receptor agonists, pasireotide (SOM230) and octreotide, with different affinity profiles for receptor subtypes. Pasireotide strikingly increased the torpor frequency in male hamsters compared with sham-treated controls, and torpor duration was often increased, which in some cases exceeded 12 h. In contrast, administration of octreotide reduced the body weight of SP hamsters but had only a marginal effect on torpor frequency in males and no effect in females. Together with measured concentrations of circulating IGF-1, the present results strongly suggest that reduced activity of the GH/IGF-1 axis is not critical for stimulation of torpor expression but activation of specific somatostatin receptors is critical. This putative role for certain somatostatin receptor subtypes in torpor induction provides a promising new approach to unravel the endocrine mechanisms of torpor regulation.
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Mzilikazi, Nomakwezi, Martin Jastroch, Carola W. Meyer, and Martin Klingenspor. "The molecular and biochemical basis of nonshivering thermogenesis in an African endemic mammal, Elephantulus myurus." American Journal of Physiology-Regulatory, Integrative and Comparative Physiology 293, no. 5 (November 2007): R2120—R2127. http://dx.doi.org/10.1152/ajpregu.00427.2007.
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Uncoupling protein 1 (UCP1) mediated nonshivering thermogenesis (NST) in brown adipose tissue (BAT) is an important avenue of thermoregulatory heat production in many mammalian species. Until recently, UCP1 was thought to occur exclusively in eutherians. In the light of the recent finding that UCP1 is already present in fish, it is of interest to investigate when UCP1 gained a thermogenic function in the vertebrate lineage. We elucidated the basis of NST in the rock elephant shrew, Elephantulus myurus (Afrotheria: Macroscelidea). We sequenced Ucp1 and detected Ucp1 mRNA and protein restricted to brown fat deposits. We found that cytochrome c oxidase activity was highest in these deposits when compared with liver and skeletal muscle. Consistent with a thermogenic function of UCP1 isolated BAT mitochondria showed increased state 4 respiration in the cold, as well as palmitate-induced, GDP-sensitive proton conductance, which was absent in liver mitochondria. On the whole animal level, evidence of thermogenic function was further corroborated by an increased metabolic response to norepinephrine (NE) injection. Cold acclimation (18°C) led to an increased basal metabolic rate relative to warm acclimation (28°C) in E. myurus, but there was no evidence of additional recruitment of NE-induced NST capacity in response to cold acclimation. In summary, we showed that BAT and functional UCP1 are already present in a member of the Afrotheria, but the seasonal regulation and adaptive value of NST in Afrotherians remain to be elucidated.
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Bocherens, Hervé, Daniel Billiou, Marylène Patou-Mathis, Dominique Bonjean, Marcel Otte, and André Mariotti. "Paleobiological Implications of the Isotopic Signatures (13C,15N) of Fossil Mammal Collagen in Scladina Cave (Sclayn, Belgium)." Quaternary Research 48, no. 3 (November 1997): 370–80. http://dx.doi.org/10.1006/qres.1997.1927.
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An isotopic investigation of upper Pleistocene mammal bones and teeth from Scladina cave (Sclayn, Belgium) demonstrated the very good quality of collagen preservation. A preliminary screening of the samples used the amount of nitrogen in whole bone and dentine in order to estimate the preserved amount of collagen before starting the extraction process. The isotopic abundances of fossil specimens from still-extant species are consistent with their trophic position. Moreover, the15N isotopic abundance is higher in dentine than in bone in bears and hyenas, a phenomenon already observed in modern specimens. These results demonstrate that the isotopic compositions of samples from Scladina cave can be interpreted in ecological terms. Mammoths exhibit a high15N isotopic abundance relative to other herbivores, as was the case in Siberian and Alaskan samples. These results suggest distinctive dietary adaptations in herbivores living in the mammoth steppe. Cave bears are clearly isotopically different from coeval brown bears, suggesting an ecological separation between species, with a pure vegetarian diet for cave bear and an omnivorous diet for brown bear.
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Capasso, Clemente, Vincenzo Carginale, Orlando Crescenzi, Daniela Di Maro, Roberta Spadaccini, Piero Andrea Temussi, and Elio Parisi. "Structural and functional studies of vertebrate metallothioneins: cross-talk between domains in the absence of physical contact." Biochemical Journal 391, no. 1 (September 26, 2005): 95–103. http://dx.doi.org/10.1042/bj20050335.
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In previous studies, we showed that the chemical and dynamic properties of fish and mouse MTs (metallothioneins) present a number of distinctive differences linked to their primary structures, and that phylogenetic relationships of mammal and fish MTs correlate with their three-dimensional structures. The different behaviours of MTs may also be linked to the interaction between their two domains. In the present study, we have compared the physicochemical properties of the isolated recombinant domains constituting Notothenia coriiceps and mouse MTs, and compared them with those of the corresponding whole MTs. NMR spectra of the separated domains of N. coriiceps are almost superimposable on those of the parent MT, suggesting an apparent lack of interaction between the two domains in the protein. However, certain dynamic and physicochemical features of the isolated domains are unlike those of the whole protein. In particular, the temperature-induced changes in the chiroptical properties, thiol reactivity of the Zn-MT domains and the Zn2+/Cd2+ rate of exchange are different for the two domains and with respect to the whole protein. Taken together, these results provide a strong argument in favour of the interaction of the two domains in the MT molecule, in spite of the elusive evidence provided by the structural analyses.
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Polanco, C., J. L. Samaniego, T. Buhse, F. G. Mosqueira, A. Negron-Mendoza, S. Ramos-Bernal, and J. A. Castanon-Gonzalez. "Characterization of Selective Antibacterial Peptides by Polarity Index." International Journal of Peptides 2012 (April 1, 2012): 1–11. http://dx.doi.org/10.1155/2012/585027.
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In the recent decades, antibacterial peptides have occupied a strategic position for pharmaceutical drug applications and became subject of intense research activities since they are used to strengthen the immune system of all living organisms by protecting them from pathogenic bacteria. This work proposes a simple and easy statistical/computational method through a peptide polarity index measure by which an antibacterial peptide subgroup can be efficiently identified, that is, characterized by a high toxicity to bacterial membranes but presents a low toxicity to mammal cells. These peptides also have the feature not to adopt to an alpha-helicoidal structure in aqueous solution. The double-blind test carried out to the whole Antimicrobial Peptide Database (November 2011) showed an accuracy of 90% applying the polarity index method for the identification of such antibacterial peptide groups.
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Spasojević, Ivan. "Integrative concept of homeostasis: translating physiology into medicine." F1000Research 3 (December 8, 2014): 299. http://dx.doi.org/10.12688/f1000research.5922.1.
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To truly understand living systems they must be viewed as a whole. In order to achieve this and to come to some law that living systems comply with, the reductionist approach, which has delivered a tremendous amount of data so far, should be complemented with integrative concepts. The current paper represents my humble attempt towards an integrative concept of homeostasis that would describe the (patho)physiological setup of adult human/mammal system, and that might be applicable in medicine. Homeostasis can be defined as time- and initial-condition-independent globally stabile state of non-equilibrium of a living system in which the interactions of system with the surroundings and internal processes are overall in balance or very near it. The presence of homeostasis or the shift from homeostasis of an adult human/mammal system can be described by equation that takes into account energy and informational input and output, catabolism and anabolism, oxidation and reduction, and entropy, where changes in the input should equal changes in the output within a specific period of time. Catabolism and oxidation are presented on the input side since the drive of the surroundings is to decompose and oxidize living systems, i.e. systems are under constant 'catabolic and oxidative pressure'. According to the equation, homeostasis might be regained by changing any of the input or output components in a proper manner (and within certain limits), not only the one(s) that has/have been changed in the first place resulting in the deviation from homeostasis.
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Erbajeva, M. A., A. A. Shchetnikov, A. Yu Kazansky, G. G. Matasova, F. I. Khenzykhenova, I. A. Filinov, O. D. Ts Namzalova, and I. O. Nechaev. "New pleistocene key section Ulan-Zhalga of the Western Transbaikalia." Доклады Академии наук 488, no. 3 (September 26, 2019): 277–81. http://dx.doi.org/10.31857/s0869-56524883277-281.
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The currant paper presents the preliminary results of the multidisciplinary study of the new Pleistocene section Ulan-Zhalga (51°29′40.75″ С, 107°20′18.11″ В) discovered in the Western Transbauikalaia in 2017. On the base of the paleontological, paleomagmetic, and lithological data the early, middle and late Pleistocene sediments were recognized in the section. The analysis of the rich small mammal fossils resulted in to trace the paleoenvironmental and climatic changes in the region during the Quaternary. The unique alternation of the 19 faunistic horizons and 11 fossil soils in the whole section, the high correlation of the paleomagnetic and paleontological data allow us to refer the studied section Ulan-Zhalga to addition new late Cenozoic Key section of the south Eastern Siberia. The new geological and paleontological data would be important for paleogeographical reconstruction and biostratigraphic analysis.
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Baker, Jason D., and Paul M. Thompson. "Temporal and spatial variation in age-specific survival rates of a long-lived mammal, the Hawaiian monk seal." Proceedings of the Royal Society B: Biological Sciences 274, no. 1608 (November 14, 2006): 407–15. http://dx.doi.org/10.1098/rspb.2006.3737.
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Estimates of variability in pinniped survival rates are generally based on observations at single sites, so it is not certain whether observed rates represent the whole population. Here, we provide a comprehensive analysis of spatio-temporal variation in age-specific survival rates for endangered Hawaiian monk seals ( Monachus schauinslandi ) based on capture–recapture analyses of more than 85% of the pups weaned in this population over the last two decades. Uniquely, these data have been collected from six subpopulations, encompassing all major breeding sites across its 1800 km long core range. Analyses of individual subpopulations revealed similar patterns in age-specific survival, characterized by the relatively low survival rates from weaning to 2 years of age, intermediate rates to 4 years of age, and then by relatively high ‘mature’ survival rates until 17 years of age, after which a senescent decline was observed. Juvenile, subadult and adult survival rates all varied significantly over time. Trends in survival among subpopulations were coherent with their relative geographical positions, suggesting regional structuring and connectedness within the archipelago. Survival rates for different age classes tended to be positively correlated, suggesting that similar factors may influence the survival for seals of all ages.
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Ulicsni, Viktor, and Dániel Babai. "Traditional Ecological Knowledge in Connection with Non-Domesticated Animals in the Slovenian and Hungarian Borderland." Acta Ethnographica Hungarica 65, no. 2 (December 31, 2020): 453–80. http://dx.doi.org/10.1556/022.2020.00020.
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Although a significant proportion of folk knowledge of nature concerns knowledge of invertebrates and vertebrates living in the wild, very little ethnozoological research has been carried out in Central Europe focusing on the whole fauna. In writing the present paper, our aim was to contribute to filling this gap by interviewing 40 local farmers who are particularly knowledgeable on this topic, half of them from the Őrség region of Hungary, and half from the neighboring villages in Slovenia, and by recording their knowledge with respect to non-domesticated animals.Our research identified the second highest number of taxa (242 species-level folk taxa) in terms of investigations carried out in the Hungarian language area in relation to the entire fauna. These included 129 invertebrate folk taxa, 73% of which were called by a species-specific name. They also included 109 vertebrate folk taxa, 103 of which had a separate species-level local name. In the case of two groups (butterflies and mammals), we also investigated attributes that were important and salient from the point of view of species knowledge: morphology and size were of particular relevance in relation to mammal species; while salient habitat features and frequency were relevant in relation to butterfly species. In the case of both groups, usefulness was the least important factor.Despite the general erosion of traditional ecological knowledge in Europe, these recently collected data indicate that a rich, vibrant knowledge is still to be found among the Hungarians whom we interviewed in the Őrség region and the neighboring villages in Slovenia. The especially large number of recorded folk taxa, and the accurate knowledge required to differentiate between them confirm, that even today it is worth carrying out investigations on this topic in East Central Europe in the interests of obtaining knowledge of, and conserving cultural and natural values.
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Watson, Simon J., Rick S. Taylor, Lisa Spence-Bailey, Dale G. Nimmo, Sally Kenny, Luke T. Kelly, Angie Haslem, et al. "The Mallee fire and biodiversity project." Proceedings of the Royal Society of Victoria 124, no. 1 (2012): 38. http://dx.doi.org/10.1071/rs12038.
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Fire is a widespread disturbance and an important ecological process in semi-arid mallee ecosystems of southern Australia. Understanding the effects of fire on plants and animals is a key challenge for the conservation and management of biodiversity in this ecosystem. Commencing in 2006, the Mallee Fire and Biodiversity Project is investigating the effects of fire on a range of taxa (vascular plants, invertebrates, reptiles, birds and mammals), with a focus on the influence of the properties of ‘fire mosaics’ on biota. A ‘whole of landscape’ design was employed, in which the flora and fauna were sampled in 28 study landscapes, each 4 km in diameter (12.5 km2) across a 104, 000 km2 area of the Murray Mallee region of Victoria, SA and NSW. Here, we summarise some key results and outputs from this project to date. These include: detailed maps of fire history and major vegetation types; a method for predicting the age of mallee vegetation; novel information about the distribution of fire age-classes in the region; and changes to vegetation structure and in the occurrence of reptile, bird and mammal species over a century-long post-fire time-frame. We also present an overview of the effects of fire mosaics (extent of particular age classes, diversity of fire age-classes) on the richness of some mallee fauna. A wealth of knowledge has been developed through the Mallee Fire and Biodiversity Project that will assist the management of mallee ecosystems in southern Australia for the future.
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Mishin, T. V. "Bycatch of marine mammals in the Northwest Atlantic during commercial fishery (based on literature materials and observations by the Polar branch of VNIRO in 2013-2020)." Vestnik MGTU 25, no. 2 (June 30, 2022): 110–19. http://dx.doi.org/10.21443/1560-9278-2022-25-2-110-119.
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This paper describes one of the most acute problem for both environmental companies and fisheries - bycatch of marine mammals caused by bioresource exploitation in the Northwest Atlantic (NWA). There is no doubt that fishing has some impact on marine mammals, but information on bycatch of marine mammals is needed to understand the extent of the impact of different fishing gears. The paper is based on data from reports of observers of the Polar branch of VNIRO from fishing vessels in the 3LMNO NAFO zone (Newfoundland Island), as well as literary materials. As a result of the analysis, it has been found that small species of marine mammals, such as gray, common, harp seals from the Phocidae family, common dolphin, short-finned pilot whale (Delphinidae family) as well as harbour porpoise from the Phocoenidae family are most often injured by various fishing gears. Toothed whales (sperm whale, bottlenose whale) are the least susceptible to bycatch. Among the baleen whales, humpback whale, northern right whale and minke whale are often the victims of fishing. Gillnets, trawl fishing, and longlines are the greatest threats to small marine mammal species, while baleen whales are most vulnerable to traps, usually to catch ten-legged crustaceans Decapoda. Analysis of the literature has shown that, in general, the stocks of most marine mammal species in the NWA, excluding the northern right whale, are in a stable condition. The manuscript considers measures aimed at reducing bycatch of marine mammals.
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Stenfors, Lars-Eric, Helga-Marie Bye, and Tapani Tikkakoski. "Shrapnell’s membrane in a mammal exposed to extreme pressure variations: morphological and radiological observations in the hooded seal." Journal of Laryngology & Otology 117, no. 10 (October 2003): 756–62. http://dx.doi.org/10.1258/002221503770716151.
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The function of Shrapnell’s membrane (pars flaccida; PF) in middle-ear mechanics is still an enigma, though numerous proposals have been put forward, e.g. protection of pars tensa, equalizing of middle-ear pressure, sound transmission, and the site of origin of otitis media. In this study the PF was studied in a mammal (the hooded seal) which exposes itself to extreme pressure differences (from 1 to 100 atmospheres) when diving.Formaldehyde-fixed temporal bones obtained from newborn, one-year-old, and adult seals (three of each) were cleansed and decalcified in 10 per cent EDTA. The lateral wall of the middle-ear cavity, including the whole tympanic membrane with its bony surroundings, was then excised and photodocumented. Thin sections were cut parallel with, and perpendicular to, the handle of the malleus, stained with haematoxylin-eosin, toluidine blue or Giemsa stain and examined under a light microscope. One seal head was subjected to high resolution computerized tomography (HRCT) before sectioning. The PF was observed to be a narrow fissure measuring a maximum of 0.8 mm between processus brevis of the malleus and the notch of Rivinus in pars squamosa (pars tensa diameter 10–12 mm). It seems unlikely that the PF of the hooded seal participates in pressure equalization in the middle ear. The main function of the lateral wall of the attic, including the minimal PF, appears to be to protect the middle-ear ossicles and allow movement of the malleus.
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Hu, Yibo, Arjun Thapa, Huizhong Fan, Tianxiao Ma, Qi Wu, Shuai Ma, Dongling Zhang, et al. "Genomic evidence for two phylogenetic species and long-term population bottlenecks in red pandas." Science Advances 6, no. 9 (February 2020): eaax5751. http://dx.doi.org/10.1126/sciadv.aax5751.
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The red panda (Ailurus fulgens), an endangered Himalaya-endemic mammal, has been classified as two subspecies or even two species – the Himalayan red panda (A. fulgens) and the Chinese red panda (Ailurus styani) – based on differences in morphology and biogeography. However, this classification has remained controversial largely due to lack of genetic evidence, directly impairing scientific conservation management. Data from 65 whole genomes, 49 Y-chromosomes, and 49 mitochondrial genomes provide the first comprehensive genetic evidence for species divergence in red pandas, demonstrating substantial inter-species genetic divergence for all three markers and correcting species-distribution boundaries. Combined with morphological evidence, these data thus clearly define two phylogenetic species in red pandas. We also demonstrate different demographic trajectories in the two species: A. styani has experienced two population bottlenecks and one large population expansion over time, whereas A. fulgens has experienced three bottlenecks and one very small expansion, resulting in very low genetic diversity, high linkage disequilibrium, and high genetic load.
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Court, Nicholas, and Mohamed Mahboubi. "Reassessment of Lower Eocene Seggeurius amourensis: aspects of primitive dental morphology in the mammalian order Hyracoidea." Journal of Paleontology 67, no. 5 (September 1993): 889–93. http://dx.doi.org/10.1017/s002233600003715x.
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New lower dental material of the fossil hyracoid mammal, Seggeurius amourensis Crochet, 1986, from Eocene deposits of the Southern Atlas in Algeria, has prompted a reevaluation of the genus. The dentition as a whole is first described in detail, thus providing a more precise characterization of the genus than has hitherto been available. Peculiarities, particularly in upper molar morphology, are sufficient to uphold a generic distinction. However, based largely on lower molar morphology Seggeurius amourensis is transferred from the subfamily Geniohyinae to Saghatheriinae. In the upper molars, absence of a postmetacrista and the presence of a preprotocrista continuous with the parastyle are interpreted as primitive features in hyracoids. In the lower molars, extreme reduction of the paracristid and the presence of a mesoconid are also considered primitive for hyracoids. These features together with small size, bunodonty, low crown height, and very simple premolar morphology indicate that Seggeurius amourensis is the most primitive hyrax yet recovered.
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Ostrander, Elaine A., Guo-Dong Wang, Greger Larson, Bridgett M. vonHoldt, Brian W. Davis, Vidhya Jagannathan, Christophe Hitte, et al. "Dog10K: an international sequencing effort to advance studies of canine domestication, phenotypes and health." National Science Review 6, no. 4 (April 10, 2019): 810–24. http://dx.doi.org/10.1093/nsr/nwz049.
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ABSTRACT Dogs are the most phenotypically diverse mammalian species, and they possess more known heritable disorders than any other non-human mammal. Efforts to catalog and characterize genetic variation across well-chosen populations of canines are necessary to advance our understanding of their evolutionary history and genetic architecture. To date, no organized effort has been undertaken to sequence the world's canid populations. The Dog10K Consortium (http://www.dog10kgenomes.org) is an international collaboration of researchers from across the globe who will generate 20× whole genomes from 10 000 canids in 5 years. This effort will capture the genetic diversity that underlies the phenotypic and geographical variability of modern canids worldwide. Breeds, village dogs, niche populations and extended pedigrees are currently being sequenced, and de novo assemblies of multiple canids are being constructed. This unprecedented dataset will address the genetic underpinnings of domestication, breed formation, aging, behavior and morphological variation. More generally, this effort will advance our understanding of human and canine health.