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1
J. Foley, William. "Marsupial Nutrition." Pacific Conservation Biology 5, no. 3 (1999): 240. http://dx.doi.org/10.1071/pc99240a.
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In the early 1980s advances in marsupial biology could no longer be encapsulated in a single volume such as Hugh Tyndale-Biscoe's "Life of Marsupials" and Cambridge University Press commissioned a series of monographs covering a range of different topics in marsupial biology. As it was, only three of that series were realized and among them was the ptedecessor to this book "Digestive Physiology and Nutrition of Marsupials" published in 1982. "Marsupial Nutrition" is a considerably expanded and comprehensive review of studies of nutrition and digestive physiology of Australasian and South American marsupials. In Australia, many ecologists view the limited nutrient status of our soils and vegetation as a fundamental limit to animal populations. This book explains firstly how Australian marsupials have responded to those limitations and secondly asks whether these responses are common amongst marsupials living in New Guinea and South America.
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Kirsch, John A. W., Mark S. Springer, and François-Joseph Lapointe. "DNA-hybridisation Studies of Marsupials and their Implications for Metatherian Classification." Australian Journal of Zoology 45, no. 3 (1997): 211. http://dx.doi.org/10.1071/zo96030.
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We review past DNA-hybridisation studies of marsupials and present a reanalysis of the data, utilising results from our and additional studies to formulate and rationalise a new classification of Marsupialia. In the reanalysis, 13 individual DNA-hybridisation matrices, many lacking some pairwise comparisons, were sutured in stages to provide the basis for generating a tree of 101 marsupials plus an outgroup eutherian; a fourteenth matrix provided data for a tree including eight additional eutherians and a monotreme. Validation was achieved by jackknifing on taxa for each matrix as well as on tables combining two or more matrices generated during assembly of the 102-taxon data set. The results are consistent with most conclusions from the individual studies and dramatise the unevenness of hierarchical levels in current classifications of marsupials. In particular, the affinities of the American marsupial Dromiciops gliroides with, and the distinctness of marsupial bandicoots from, Australasian metatherians are reaffirmed, while opossums are shown to be as internally divergent as are most members of the order Diprotodontia. Calibration of the 102-taxon tree and dating of the major dichotomies suggest that no extant marsupial lineage originated before the latest Cretaceous, and that all of them together with most South American and all Australasian fossils should be recognised as a monophyletic group contrasting with a largely Laurasian (if possibly paraphyletic) taxon. These inferences, together with the details of the phylogeny, mandate that the misleading ‘Australian’ v. ‘American’ distinction be abandoned, even as a geographic convenience.
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Pevsner, Spencer K., David M. Grossnickle, and Zhe-Xi Luo. "The functional diversity of marsupial limbs is influenced by both ecology and developmental constraint." Biological Journal of the Linnean Society 135, no. 3 (January 4, 2022): 569–85. http://dx.doi.org/10.1093/biolinnean/blab168.
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Abstract Extant marsupials are less ecologically diverse than placentals, and this is reflected by placentals exhibiting a greater diversity of locomotor modes, including powered flight and fully aquatic swimming. One proposed explanation for this discrepancy is that the development of more disparate marsupial forelimbs is prevented by the neonate’s crawl to the pouch, which requires precocious forelimb development for climbing adaptations. To test predictions of this Developmental Constraint Hypothesis (DCH), we pursue a comparative morphometric study on osteological traits of mammalian limbs, with an emphasis on functional differentiation of marsupial limbs among locomotor modes. We apply multivariate analyses to a large dataset of limb metrics and a diverse sample of mammals, with the placental sample limited to taxa whose locomotor modes are exhibited in marsupials. Overall, we do not find consistent evidence in support of the DCH. Diprotodontia serves as an exception, with comparisons of their forelimbs to hind limbs supporting the DCH. Our results suggest that developmental constraints on marsupial forelimbs may have limited marsupial diversity to some degree. Despite this, the marsupial locomotor groups show unexpectedly high levels of morphological differentiation relative to placentals of the same locomotor modes, indicating that ecological functions may overcome developmental constraints on a macroevolutionary scale.
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Harvey, Paul H. "Evolutionary ecology of marsupials." Animal Behaviour 34 (February 1986): 309–10. http://dx.doi.org/10.1016/0003-3472(86)90051-5.
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Cowan, P. E. "Evolutionary ecology of marsupials." Journal of the Royal Society of New Zealand 17, no. 4 (December 1987): 426–27. http://dx.doi.org/10.1080/03036758.1987.10430738.
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Main, A. R. "Evolutionary ecology of marsupials." Endeavour 9, no. 4 (January 1985): 208. http://dx.doi.org/10.1016/0160-9327(85)90099-7.
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Sunquist, Mel. "Evolutionary ecology of marsupials." Behavioural Processes 14, no. 3 (June 1987): 344–46. http://dx.doi.org/10.1016/0376-6357(87)90079-9.
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Cockburn, A. "Sex-Ratio Variation in Marsupials." Australian Journal of Zoology 37, no. 3 (1989): 467. http://dx.doi.org/10.1071/zo9890467.
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Many marsupials produce sex ratios biased towards male or female young. In several cases these changes are comfortably accommodated in the existing theory of sex allocation. Local resource competition and the Trivers-Willard hypothesis have been usefully applied to several data sets, and preliminary experimental work has supported the main tenets of theory. By contrast, several data sets lack explanation, and provide challenges to theoreticians. The high frequency of bias in marsupials does not result from data-dredging, as bias is usually reported in descriptive accounts of marsupial reproduction, without recourse to any theoretical or mechanistic explanations. It is not possible to distinguish whether the marsupial mode of reproduction is well suited to manipulate sex allocation, or whether it facilitates measurement of biased sex allocation. As for most eutherians and birds, the mechanism of prenatal sex allocation is unknown for any marsupial. However, the current interest in sex-determining mechanisms in marsupials suggests a profitable avenue for collaboration between geneticists, physiologists and evolutionary ecologists.
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Deakin, Janine E. "Marsupial X chromosome inactivation: past, present and future." Australian Journal of Zoology 61, no. 1 (2013): 13. http://dx.doi.org/10.1071/zo12113.
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Marsupial and eutherian mammals inactivate one X chromosome in female somatic cells in what is thought to be a means of compensating for the unbalanced X chromosome dosage between XX females and XY males. The hypothesis of X chromosome inactivation (XCI) was first published by Mary Lyon just over 50 years ago, with the discovery of XCI in marsupials occurring a decade later. However, we are still piecing together the evolutionary origins of this fascinating epigenetic mechanism. From the very first studies on marsupial X inactivation, it was apparent that, although there were some similarities between marsupial and eutherian XCI, there were also some striking differences. For instance, the paternally derived X was found to be preferentially silenced in marsupials, although the silencing was often incomplete, which was in contrast to the random and more tightly controlled inactivation of the X chromosome in eutherians. Many of these earlier studies used isozymes to study the activity of just a few genes in marsupials. The sequencing of several marsupial genomes and the advent of molecular cytogenetic techniques have facilitated more in-depth studies into marsupial X chromosome inactivation and allowed more detailed comparisons of the features of XCI to be made. Several important findings have come from such comparisons, among which is the absence of the XIST gene in marsupials, a non-coding RNA gene with a critical role in eutherian XCI, and the discovery of the marsupial RSX gene, which appears to perform a similar role to XIST. Here I review the history of marsupial XCI studies, the latest advances that have been made and the impact they have had towards unravelling the evolution of XCI in mammals.
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Sherwin, WB, and ND Murray. "Population and Conservation Genetics of Marsupials." Australian Journal of Zoology 37, no. 3 (1989): 161. http://dx.doi.org/10.1071/zo9890161.
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This article summarises current knowledge of marsupial population genetics, and discusses its relevance to the conservation of marsupial species. It has been suggested that there is much lower genetic variation within marsupial populations than in eutherian mammals. This trend is not evident in the electrophoretic data summarised here. However, genetic differentiation between populations, subspecies, and species of marsupials appears to be slightly lower than comparable values for eutherians. Genetic estimates of migration between populations are scarce at present, but show values that are comparable with eutherians. Some studies of marsupial population genetics have used non-electrophoretic characteristics, or have addressed the possibility of selection on the characters analysed. Although few, these studies indicate the suitability of marsupials for such investigations. Recent debate over the theories and applications of conservation genetics has made it clear that more research is required on individual species. Given the record of extinction of marsupials in the last 200 years, it is important to test the applicability of these theories to individual marsupial species. Several examples are discussed emphasising the need for ecological studies that estimate the effective number of reproducing individuals per generation. This figure, called the effective size, is the corner- stone of conservation genetics theory, being an important determinant of both the rate of loss of variation between individuals, and the rate of inbreeding. The effective size of the mainland population of the eastern barred bandicoot, Perameles gunnii, appears to be only about one-tenth of its census number. This result is comparable with estimates made in other vertebrates, and demonstrates that many marsupial species which appear to have an adequate census size on ecological grounds may face genetic problems resulting from small effective size.
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MARTIN, JENNY. "Marsupials." Austral Ecology 32, no. 6 (September 2007): 719–20. http://dx.doi.org/10.1111/j.1442-9993.2007.01780.x.
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Keast, Allen. "Evolutionary Ecology of Marsupials. Monographs on Marsupial Biology.Anthony K. Lee , Andrew Cockburn." Quarterly Review of Biology 61, no. 1 (March 1986): 120. http://dx.doi.org/10.1086/414813.
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Griffiths, M., and N. G. Simms. "Observations on the anatomy of mammary glands in two species of conilurine rodent (Muridae: Hydromyinae) and in an opossum (Marsupialia: Didelphidae)." Australian Mammalogy 16, no. 1 (1993): 9. http://dx.doi.org/10.1071/am93002.
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The pups of Pseudomys nanus and P. australis are attached to their mothers' teats for extended periods of time, analogous to the situation encountered in pouchless marsupials. The structures in the mammary glands involved in facilitating prolonged attachment are different in the two rodent species and both kinds are different from those in marsupial glands including those of Monodelphis domestica, the subject of the present study. In P. nanus, the teats are anchored to postero-ventrally directed, tubular diverticula of the body wall. In P. australis there are no diverticula. However, support for the mammary glands and teats is afforded by the body wall, in the form of two well-developed fan-shaped muscles dorsal to the mammary glands in conjunction with a broad lamina of connective tissue, smooth and striated muscle situated between the skin of the belly and the mammary glands. In M. domestica, the teats are anchored to swathes of striated voluntary muscle, derived from the ilio-marsupialis muscles which pass ventrally through the secretory parenchyma to be inserted onto the bases of the teats. Since this musculature has not been observed in the mammary glands of any eutherians so far studied, nor in those of Monotremata, it is put that it is a character unique to the Marsupialia.
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Cruz-Salazar, Bárbara, and Lorena Ruiz-Montoya. "Population viability analysis of common marsupials, Didelphis marsupialis and Didelphis virginiana, in a scenario of constant loss of native vegetation." Mammalia 84, no. 5 (September 25, 2020): 475–82. http://dx.doi.org/10.1515/mammalia-2019-0130.
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AbstractWe studied the population viability of two common marsupials, Didelphis marsupialis and Didelphis virginiana, based on field data and published ecological and genetic information. Using the VORTEX v. 10. 2.6 program, a 100-year simulation was performed with 1000 iterations for five populations of D. marsupialis and six of D. virginiana. A low probability of extinction was observed in both species, particularly for D. virginiana (0.000–0.007). Population size is higher considering a metapopulation dynamics approach versus individual populations for the two marsupials: 498.25 individuals for D. marsupialis and 367.41 individuals for D. virginiana. The estimated mean genetic diversity was high for both D. marsupialis (He = 0.77–0.78) and D. virginiana (He = 0.79–0.82). The survival of both species over time could be expected to increase if a metapopulation dynamics is favored over the coming decades, despite a 1.3% loss rate of forest cover. The monitoring of population size and genetic diversity is highly recommended to validate the trends suggested by the model; this is especially true for D. marsupialis, a species associated with conserved areas that are becoming progressively less abundant. This research provides information on the responses of common mammalian species to environmental changes such as deforestation.
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Cooper, DW, PG Johnston, JL Vandeberg, and ES Robinson. "X-Chromosome Inactivation in Marsupials." Australian Journal of Zoology 37, no. 3 (1989): 411. http://dx.doi.org/10.1071/zo9890411.
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Marsupial (metatherian) mammals resemble their eutherian ('placental') counterparts in having inacti- vation of one of the two X chromosomes in the soma and premeiotic germ cells of their females. The marsupial X-inactivation system differs from the eutherian system in two respects: firstly, inactivation occurs for the paternally derived allele, i.e. it is not random, and secondly it is often incomplete. Data are available for four X-linked loci, all controlling enzyme structure: glucose-6- phosphate dehydrogenase (G6PD), phosphoglycerate kinase 1 (PGKl), alpha-galactosidase (GLA) and hypoxanthine phosphoribosyl transferase (HPRT). Both the G6PD and PGKl loci exhibit incomplete X-chromosome inactivation. The pattern of partial expression differs from tissue to tissue and from species to species. One of the two X chromosomes exhibits late replication, even in cells where a paternally derived gene is partly active, showing that late replication and absence of transcription are not completely correlated. Sex chromatin bodies are not as easily found as in some eutherians. In marsupials they are most clearly demonstrable in species with small Y chromosomes. Investigations into X-inactivation in early development have just begun. Absence of inactivation at the G6PD locus in yolk sac of a kangaroo has been observed. All other tissues exhibited complete paternal X-inacti- vation for G6PD. In a dasyurid, GLA showed complete paternal X-inactivation in all embryonic and extra-embryonic tissues. The role, if any, of methylation of cytosine residues in CpG pairs in the maintenance of X-inactivation in marsupials is unclear. Preliminary evidence indicates that sex-specific differences in methylation of sex linked genes do exist in marsupials.
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Rodger, JC. "Prospects for the Artificial Manipulation of Marsupial Reproduction and Its Application in Research and Conservation." Australian Journal of Zoology 37, no. 3 (1989): 249. http://dx.doi.org/10.1071/zo9890249.
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Techniques to manipulate reproduction and productivity are well established features of the husbandry of domestic animals and the treatment of human infertility. Similar approaches are feasible in marsupials, but little work has been done to apply our considerable basic knowledge of marsupial reproduction to produce practical artificial breeding. If the reproduction and productivity of marsupials could be more effectively controlled it would greatly aid research and profoundly change both current practice in the management of zoo animals, and the strategies employed for the breeding and conservation of rare or endangered species. The present paper sets out the likely agenda, reports progress to date and discusses short and long-term prospects for the artificial breeding of marsupials. Topics discussed include: induced ovulation and superovulation, oocyte and embryo collection, semen collection and the frozen storage of sperm, artificial insemination, in vitro fertilization and embryo transfer, frozen storage of embryos, and the use of surrogate mothers in supporting both pregnancy to term, and the development of young in the pouch.
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Graves, Jennifer A. Marshall. "Kangaroo gene mapping and sequencing: insights into mammalian genome evolution." Australian Journal of Zoology 61, no. 1 (2013): 4. http://dx.doi.org/10.1071/zo13002.
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The deep divergence of marsupials and eutherian mammals 160 million years ago provides genetic variation to explore the evolution of DNA sequence, gene arrangement and regulation of gene expression in mammals. Following the pioneering work of Professor Desmond W. Cooper, emerging techniques in cytogenetics and molecular biology have been adapted to characterise the genomes of kangaroos and other marsupials. In particular, genetic and genomic work over four decades has shown that marsupial sex chromosomes differ significantly from the eutherian XY chromosome pair in their size, gene content and activity. These differences can be exploited to deduce how mammalian sex chromosomes, sex determination and epigenetic silencing evolved.
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Lapointe, FJ, and JAW Kirsch. "Construction And Verification Of A Large Phylogeny Of Marsupials." Australian Mammalogy 23, no. 1 (2001): 9. http://dx.doi.org/10.1071/am01009.
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Much of the controversy over marsupial phylogeny at higher-categorical levels stems from the piecemeal nature of the contributing studies or the paucity of taxonomic representation in many of them. Yet the problems of constructing large phylogenies are manyfold, involving the initial generation of the data as well as their efficient analysis. Often unaddressed, also, is the need to validate extremely large data sets and trees. Many of these problems can be ameliorated by treating the data as distances (or generating distances directly). We show that, contrary to the assertions of many protagonists in the total-evidence versus consensus debate, the validated data and pathlength (tree) matrices usually give very similar results, although a few additional unstable nodes may be found when the results of internal and external validations are themselves combined in a global-congruence test. Here we illustrate our protocols with a 109-taxon data set, representing combination of marsupial DNA-hybridisation data with similar information on a series of outgroups. Phylogenetically, the results affirm the marsupial groupings we have previously found, and suggest but do not unambiguously support a nearer relationship of monotremes than placentals to marsupials. This paper represents the first attempt to validate the tree of 101 marsupials presented earlier.
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Jolly, SE, GA Morriss, S. Scobie, and PE Cowan. "Composition of Milk of the Common Brushtail Possum, Trichosurus Vulpecula (Marsupialia: Phalangeridae): Concentrations of Elements." Australian Journal of Zoology 44, no. 5 (1996): 479. http://dx.doi.org/10.1071/zo9960479.
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The concentrations of 11 elements (calcium, copper, iron, magnesium, manganese, phosphorus, potassium, sodium, strontium, sulphur and zinc) were measured in milk samples collected from 193 lactating brushtail possums, Trichosurus vulpecula, at all stages of lactation. Most elements showed patterns of change during lactation similar to those of other marsupials. The most marked changes occurred at about 80-120 days, when the growth rate of the pouch young increased and developmental changes took place, such as eye opening and fur growth. Compared with eutherians, copper and iron concentrations were high in possum milk, as in other marsupials, but zinc levels were exceptionally high. Strontium and manganese levels, not measured before in marsupial milk, were considerably higher than levels reported in eutherian milk. In contrast to eutherian mammals, marsupial young must be supplied with large quantities of minerals in the milk as almost all growth and development occurs after birth, and possum young are entirely dependent on milk supplied by the mother for about the first 100 days.
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Snipes, RL, H. Snipes, and FN Carrick. "Morphometric data on the intestines of five Australian marsupials (Marsupialia)." Australian Mammalogy 25, no. 2 (2003): 193. http://dx.doi.org/10.1071/am03193.
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THE nutritional biology of marsupials has been a subject of numerous studies, culminating in valuable compilations covering a wide range of aspects (Osman Hill and Rewell 1954; Walton and Richardson 1989; Hume 1982, 1999; Kerle 2001). Despite this thorough coverage, there remains a scarcity of morphometric data on the intestines of monotremes and marsupials. In an attempt to approach this need, an effort was initiated to provide morphometric data on monotremes (Snipes et al. 2002) and marsupials (Snipes et al. 1993, 2003).
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Belov, Katherine, Robert D. Miller, Julie M. Old, and Lauren J. Young. "Marsupial immunology bounding ahead." Australian Journal of Zoology 61, no. 1 (2013): 24. http://dx.doi.org/10.1071/zo12111.
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Marsupial immune responses were previously touted as ‘primitive’ but we now know that the marsupial immune system is complex and on par with that of eutherian mammals. In this manuscript we review the field of marsupial immunology, focusing on basic anatomy, developmental immunology, immunogenetics and evolution. We concentrate on advances to our understanding of marsupial immune gene architecture, made possible by the recent sequencing of the opossum, tammar wallaby and Tasmanian devil genomes. Characterisation of immune gene sequences now paves the way for the development of immunological assays that will allow us to more accurately study health and disease in marsupials.
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Beyer, Georgia L., and Ross L. Goldingay. "The value of nest boxes in the research and management of Australian hollow-using arboreal marsupials." Wildlife Research 33, no. 3 (2006): 161. http://dx.doi.org/10.1071/wr04109.
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Nest boxes have been recognised as research and management tools for arboreal marsupials in Australia for over 20 years. We review the published literature with the aim of describing the scope of studies conducted in Australia thus far and providing guidance to future research. We recognise three types of application in research: (1) detection of species, (2) study of a species’ ecology, and (3) investigation of box designs preferred by different species. Several species of arboreal marsupial may be detected more readily in nest boxes than by conventional survey techniques, allowing description of key aspects of their ecology; e.g. feathertail glider (Acrobates pygmaeus), eastern pygmy possum (Cercartetus nanus) and brush-tailed phascogale (Phascogale tapoatafa). Identifying the most favoured nest-box design for any species has implications for detection and management uses of nest boxes. More research is needed but preliminary findings suggest that species prefer narrow entrance holes, while height of the nest box above 3 m may be inconsequential. We recognise three types of management application: (1) species introduction, (2) support of populations of endangered species, and (3) strategic placement such as to enhance habitat connectivity. Currently there have been few attempts to use nest boxes to manage arboreal marsupials but further research is needed to realise their potential as a management tool.
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JARMAN, PETER J. "Life of Marsupials." Austral Ecology 31, no. 5 (August 2006): 670. http://dx.doi.org/10.1111/j.1442-9993.2006.01646.x.
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Churcher, C. S. "Dental functional morphology in the marsupial sabre-tooth Thylacosmilus atrox (Thylacosmilidae) compared to that of the felid sabre-tooths." Australian Mammalogy 8, no. 4 (October 1, 1985): 201–20. http://dx.doi.org/10.1071/am85020.
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The South American Middle to Late Pliocene fauna of Argentina included the borhyaenid marsupials Thylacosmilus atrox and Notosmilus pattersoni, the latter known only from a single Late Pliocene occurrence. Thylacosmilus atrox has been interpreted as a marsupial with a carnivorous specialisation convergent on the fissipede and machairodont sabre-tooths of Eurasia, Africa and North America. Thylacosmilus atrox superficially resembles placental sabre-tooths in general conformation but also shows remarkable divergences, some of which are attributable to its marsupial ancestry.
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Hayman, DL. "Marsupial Cytogenetics." Australian Journal of Zoology 37, no. 3 (1989): 331. http://dx.doi.org/10.1071/zo9890331.
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This review includes a list of the chromosome numbers of marsupials and a summary of the main features of chromosome evolution in this group of mammals. Special topics discussed include sex chromosome mosaicism, the size of the marsupial X chromosome, X chromosomes and nucleolar organisers, complex sex chromosome systems, repeated DNA sequences and aspects of meiosis.
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Westerman, M. "Phylogenetic-Relationships of the Marsupial Mole, Notoryctes-Typhlops (Marsupialia, Notoryctidae)." Australian Journal of Zoology 39, no. 5 (1991): 529. http://dx.doi.org/10.1071/zo9910529.
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The phylogenetic position of the marsupial mole, Notorcytes typhlops, has been difficult to ascertain with morphological characters because of its highly specialised fossorial lifestyle. On the basis of serological data, Kirsch (1977b) suggested that this species was sufficiently different from other marsupials to warrant placing it in its own suborder. Using the DNA-DNA hybridisation technique on single-copy DNA to assess sequence differences over the entire genome, I confirm that N. typhlops is not closely related to any other marsupial family, and warrants placement in its own order.
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Messer, M., D. C. Shaw, A. S. Weiss, P. Rissmiller, and M. Griffiths. "Estimation of Divergence Dates for Monotremes From Comparisons of A-Lactalbumin Amino Acid Sequences." Australian Mammalogy 20, no. 2 (1998): 310. http://dx.doi.org/10.1071/am98323.
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cx-Lactalbumins were isolated from milk of the platypus (Ornithorhynchus anatinus) and the echidna (Tachyglossus aculeatus). Their amino acid sequences were determined and compared with those of the cx- lactalbumins often eutherian and two marsupial species, using the computer programme ("Distances") to calculate the number of differences (substitutions) between a total of 36 pairs of cx-lactalbumins. As expected, the amino acid sequences of the monotreme cx-lactalbumins were more similar to each other than to those of other mammals, as were the sequences of the marsupial and the eutherian cx-lactalbumins. If one makes the common assumption that marsupials and eutherians diverged from each other 135 Myr ago then simple calculations from the data would suggest that the platypus and echidna lineages diverged 56 ± 8 (SD) Myr ago and that monotremes diverged from the other mammals 152 ± 29 Myr ago. These values are not inconsistent with the little that is known about the palaeontology of the monotremes and are very similar to those derived from previous studies on globin sequences. If, however, monotreme cx-lactalbumins evolved more slowly than the cx-lactalbumins of eutherians and marsupials, these dates could be underestimates.
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Simmonds, Michael J., Oguz K. Baskurt, Herbert J. Meiselman, Michael Pyne, Michael Kakanis, Ekua Brenu, James Keane, Rhys Christy, and Sonya M. Marshall-Gradisnik. "Haemorheology of the eastern grey kangaroo and the Tasmanian devil." Australian Journal of Zoology 59, no. 1 (2011): 26. http://dx.doi.org/10.1071/zo10083.
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The blood of two Australian marsupials, the eastern grey kangaroo (Macropus giganteus) and the Tasmanian devil (Sarcophilus harrisii), has been reported to have greater oxygen-carrying capacity (i.e. haemoglobin content) when compared with that of placental mammals. We investigated whether alterations of blood rheological properties are associated with the increased oxygen-carrying capacity of these marsupials. Eastern grey kangaroos (n = 6) and Tasmanian devils (n = 4) were anaesthetised for blood sampling; human blood (n = 6) was also sampled for comparison. Laboratory measurements included blood and plasma viscosity, red blood cell (RBC) deformability, RBC aggregation and the intrinsic tendency of RBC to aggregate, RBC surface charge and haematological parameters. Scanning electron micrographs of RBC from each species provided morphological information. High-shear blood viscosity at native haematocrit was highest for the Tasmanian devil. When haematocrit was adjusted to 0.4 L L–1, lower-shear blood viscosity was highest for the eastern grey kangaroo. RBC deformability was greatly reduced for the Tasmanian devil. Eastern grey kangaroo blood had the highest RBC aggregation, whereas Tasmanian devil RBC did not aggregate. The surface charge of RBC for marsupials was ~15% lower than that of humans. The dependence of oxygen-delivery effectiveness on haemoglobin concentration (i.e. oxygen content) and blood viscosity was quantitated by calculating the haematocrit to blood viscosity ratio and was 15–25% lower for marsupials compared with humans. Our results suggest that environmental pressures since the marsupial–monotreme divergence have influenced the development of vastly different strategies to maintain a match between oxygen demand and delivery.
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Ferreira, Mariana Silva, Rui Cerqueira, and Marcus Vinícius Vieira. "What are the main drivers of survival and recruitment in tropical forest marsupials? A 16-year study." Journal of Mammalogy 101, no. 2 (February 22, 2020): 515–25. http://dx.doi.org/10.1093/jmammal/gyaa013.
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Abstract Tropical forest marsupials exhibit large interannual variation in population sizes, with direct negative density dependence capturing the essential features of their dynamics. However, the demographic mechanisms underlying population growth rate and driving both survival and reproduction are still unclear. We used a 16-year capture-mark-recapture data set for five tropical forest marsupials to test for seasonal and interannual density dependence in survival and recruitment. Hypotheses regarding the effects of exogenous (rainfall and minimum temperature) factors on survival, recruitment, and reproductive parameters (fecundity, litter size, and proportion of reproductive females) were also tested. Population size negatively affected survival in three of five species. High population sizes in a given year reduced survival rates in the following year, with strong detrimental effects on males. Recruitment and proportion of reproductive females were highly dependent on weather variables, and were not affected by previous population sizes (except for Metachirus nudicaudatus). Fecundity (number of female offspring/female) was related negatively to population size only in the black-eared opossum (Didelphis aurita), while litter size was a relatively conservative parameter, largely independent of external conditions. Our analyses indicate that density-dependent survival is the mechanism that regulates population size of tropical forest marsupials, either through a reduction in survival or an increase in emigration rates. This general regulatory mechanism may be common to other marsupials in the Atlantic Forest and other tropical forests. Marsupiais de florestas tropicais exibem grande variação interanual nos tamanhos populacionais, com dependência negativa e direta da densidade capturando a essência de sua dinâmica populacional. No entanto, os mecanismos demográficos subjacentes à taxa de crescimento populacional e determinantes da sobrevivência e reprodução ainda são incertos. Nós usamos 16 anos de dados de captura-marcação-recaptura de cinco espécies de marsupiais de florestas tropicais para avaliar a dependência de densidade sazonal e interanual na sobrevivência e recrutamento. Hipóteses sobre efeitos de fatores exógenos (pluviosidade e temperatura mínima) na sobrevivência, recrutamento e parâmetros reprodutivos (fecundidade, tamanho da ninhada e proporção de fêmeas reprodutivas) também foram testadas. O tamanho da população afetou negativamente a sobrevivência em três das cinco espécies. O tamanho populacional elevado em um ano reduziu as taxas de sobrevivência no ano seguinte, com efeitos mais negativos nos machos. Recrutamento e proporção de fêmeas reprodutivas foram dependentes das variáveis climáticas e não foram afetados pelos tamanhos populacionais anteriores (com exceção de Metachirus nudicaudatus). A fecundidade (número de filhotes fêmea/fêmea) foi relacionada negativamente ao tamanho da população do gambá-de-orelha-preta (Didelphis aurita), enquanto o tamanho da ninhada foi um parâmetro relativamente conservador e independente das condições externas. Nossas análises indicam que a sobrevivência dependente da densidade regula as populações de marsupiais em florestas tropicais, seja através da redução na sobrevivência ou no aumento da emigração. Esse mecanismo regulatório pode ser comum a outros marsupiais na Mata Atlântica e outras florestas tropicais.
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Firestone, K. B. "Isolation and characterization of microsatellites from carnivorous marsupials (Dasyuridae: Marsupialia)." Molecular Ecology 8, no. 6 (June 1999): 1084–86. http://dx.doi.org/10.1046/j.1365-294x.1999.00655_6.x.
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Geiser, F. "Hibernation and Daily Torpor in Marsupials - a Review." Australian Journal of Zoology 42, no. 1 (1994): 1. http://dx.doi.org/10.1071/zo9940001.
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Most heterothermic marsupials appear to display one of the two patterns of torpor that have been described in placental mammals. During shallow, daily torpor body temperature (T(b)) falls for several hours from about 35-degrees-C to values between 11 and 28-degrees-C, depending on the species, and metabolic rates fall to about 10-60% of the basal metabolic rate (BMR). In contrast during deep and prolonged torpor (hibernation), T(b) falls to about 1-5-degrees-C, metabolic rates to about 2-6% of BMR and torpor bouts last for 5-23 days. Shallow, daily torpor has been observed in the opossums (Didelphidae), the carnivorous marsupials (Dasyuridae) and the small possums (Petauridae). Daily torpor may also occur in the numbat (Myrmecobiidae) and the marsupial mole (Notoryctidae). Deep and prolonged torpor (hibernation) has been observed in the pygmy possums (Burramyidae), feathertail glider (Acrobatidae) and Dromiciops australis (Microbiotheriidae). The patterns of torpor in marsupials are paralleled by those of monotremes, placentals and even birds. These similarities in torpor patterns provide some support to the hypothesis that torpor may be plesiomorphic. However, as endothermy and torpor in birds apparently has evolved separately from that in mammals and as torpor occurrence in mammals can change within only a few generations it appears more likely that torpor in endotherms is convergent.
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Irlbeck, NA, and ID Hume. "The role of Acacia in the diets of Australian marsupials ? A review." Australian Mammalogy 25, no. 2 (2003): 121. http://dx.doi.org/10.1071/am03121.
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Many of the 600 species of Acacia found in Australia form part of the diet of several groups of marsupials. Acacia foliage is generally high in tannins but is consumed by several folivorous possums and by some macropods (kangaroos and wallabies), but the macropods eat it mainly as dry leaf litter during times of food shortage (in dry seasons and drought). Acacia gum is an important diet component of two omnivorous possums (Petaurus breviceps, Gymnobelidius leadbeateri) and, to a lesser extent, two rat-kangaroos (Bettongia sp.). Acacia seeds are consumed by marsupials to a limited extent, but are an important seasonal component of the diet of the mountain brushtail possum (Trichosurus cunninghami), and possibly the tammar wallaby (Macropus eugenii) on Kangaroo Island. Likewise, Acacia arils (lipid-rich appendages to the seeds of some species) are an important seasonal component of the diet of the mahogany glider (Petaurus gracilis). Acacia pollen and nectar are consumed by several omnivorous possums (e.g., Petaurus norfolcensis) as well as by at least one species of rock-wallaby (Petrogale sp.), but the quantitative contributions made by these floral products to the protein and energy budgets of the consumers have been difficult to determine. Thus several parts of the Acacia plant are food resources for one or more groups of marsupials, but the contribution of the genus to marsupial nutrition is often overlooked.
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Taggart, D. A., D. Schultz, and P. D. Temple-Smith. "Development and Application of Assisted Reproductive Technologies in Marsupials: Their Value for Conservation of Rock-wallabies." Australian Mammalogy 19, no. 2 (1996): 183. http://dx.doi.org/10.1071/am97183.
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Assisted reproductive technology is used routinely in management to treat infertility and in domestic species in basic husbandry. In eutherian mammals application of this technology is also well established in wildlife conservation programs. The development and application of this technology in marsupials, however, is a relatively new field. The reproductive techniques currently available for marsupial studies, their benefits and implications for conservation are discussed in order to remove any previous misconceptions and provide an insight into how these techniques might be applied. The potential of this technology for maintaining genetic variability and enhancing reproductive output of threatened marsupial species is highlighted, with particular reference to the conservation of rock wallabies.
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Riley, J., DM Spratt, and PJA Presidente. "Pentastomids (Arthropoda) Parasitic in Australian Reptiles and Mammals." Australian Journal of Zoology 33, no. 1 (1985): 39. http://dx.doi.org/10.1071/zo9850039.
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Records of pentastomid arthropods parasitic in Australian reptiles and mammals are reviewed, with particular reference to material collected recently. Specimens representative of six genera are described. Sebekia sp. from the estuarine crocodile, Crocodylusporosus, is the first record of the genus in Australia and probably represents a new species. A nymph with double hooks, from the dasyurid marsupial Satanellus hallucatus, is determined as Waddycephalus sp. This represents the first evidence of double hooks in nymphal forms of the genus and of the role of marsupials as intermediate hosts of Waddycephalus. Nymphs from the peramelid marsupial, Isoodon macrourus, and from S, hallucatus are determined as Armillifer australis Riley & Self, 1981; those from Perameles nasuta are identified as A. arborealis Riley & Self, 1981. These represent the first records of marsupials as intermediate hosts of Armillifer. Adults of the genus Elenia Heymons, 1932 are confirmed as parasites of varanid lizards. E. australis Heymons, 1932 is recognized and it is suggested that specimens described by Heymons (1939), allegedly from Varanus varius at Townsville, Qld, may represent a new species. The cosmopolitan porocephalid Linguatula serrata Frolich, 1789 is recorded from the nasopharynx of the dingo or wild dog and the validity of the indigenous species, L. dingophila Johnson, 1910 is discussed. The cephalobaenid Raillietiella amphiboluri Mahon, 1954 is reported from Amphibolurus barbatus.
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Williams, W. F., Hugh Tyndale-Biscoe, and Marilyn Renfree. "Reproductive Physiology of Marsupials." Journal of Wildlife Management 53, no. 2 (April 1989): 511. http://dx.doi.org/10.2307/3801160.
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Shaw, Geoff, and Marilyn B. Renfree. "Parturition and perfect prematurity: birth in marsupials." Australian Journal of Zoology 54, no. 3 (2006): 139. http://dx.doi.org/10.1071/zo05070.
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Marsupials are distinguished from eutherian mammals in their mode of reproduction. They give birth to a highly altricial young, which completes its development whilst attached to a teat, usually within a pouch. The marsupial neonate has relatively well-developed digestive, respiratory and circulatory systems but retains its fetal excretory system with a fully functional mesonephric kidney and undifferentiated gonads and genitalia. We have investigated birth in the tammar wallaby (Macropus eugenii) and shown that the tiny (400 mg) fetus determines the time of its own delivery. Although plasma progesterone falls, and oestradiol associated with the postpartum oestrus typically rises, around the time of parturition, neither hormone is essential for the timing of birth. However relaxin may loosen the connective tissue of the cervix and vaginae for birth. Labour starts suddenly and is completed within minutes. Both prostaglandins and mesotocin are essential for the contractions that deliver the young. Prostaglandins from the reproductive tract act via the brain to control parturient behaviour. In the last 2 days of gestation fetal adrenal glucocorticoid production increases, promoting lung maturation and surfactant production and ultimately triggering labour. The accessibility of the altricial neonatal marsupial provides a unique opportunity for experimental manipulation of organ development and maturation.
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Harman, AM. "The Optic Chiasm of Australian Marsupials." Australian Journal of Zoology 43, no. 5 (1995): 467. http://dx.doi.org/10.1071/zo9950467.
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The optic chiasm of mammals is the region of the nervous system in which optic axons have a choice of route, either they enter the optic tract on the same side of the brain or they cross the chiasm and enter the opposite optic tract. in eutherian (placental) mammals, axons approach the midline of the chiasm and then either continue across the chiasm or turn back to enter the tract on the same side of the brain. The midline of the chiasm provides guidance cues that repel uncrossed but not crossed axons. However, it has recently been shown that in a marsupial, the quokka wallaby, axons destined to stay on the same side of the brain remain in the lateral part of the optic nerve and chiasm and never approach the midline. The structure of the chiasm reflects this partitioning of axons with different routes by having a tripartite structure. The two lateral regions contain only uncrossed axons in rostral chiasmatic regions and the central region contains only crossed axons. Therefore, axons passing through the chiasm of this species must use guidance cues that differ from those of eutherian mammals. Here I show that the chiasms of species of both diprotodont and polyprotodont Australian marsupials have a similar tripartite structure and that uncrossed axons are confined to lateral regions. It seems likely, therefore, that the chiasm of marsupials has fundamental differences in structure and optic axon trajectory compared with that of eutherian mammals studied to date.
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van Tets, I. G. "Can Flower-Feeding Marsupials Meet Their Nitrogen Requirements on Pollen in The Field?" Australian Mammalogy 20, no. 3 (1998): 383. http://dx.doi.org/10.1071/am98383.
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Two arboreal marsupials, the eastern pygmy possum (Cercartetus nanus) and the sugar glider (Petaurus breviceps) have exceptionally low maintenance nitrogen requirements on pollen diets. This study compares their nitrogen requirements with the density of Banksia pollen that is available in the Barren Grounds Nature Reserve, New South Wales, a site where both species are known to forage on Banksia inflorescences. The pollen density was sufficiently high that both species were capable of meeting their maintenance nitrogen requirements on pollen whenever Banksia spp. were in flower. C. nanus required a smaller proportion of its home range than P. breviceps to do so and pollen was likely to be of much greater nutritional significance to both species in winter than in summer. This corresponds closely with the results of field studies comparing the diets of these mammals at different times of the year. Pollen is an important source of nitrogen for flower-feeding marsupials but its importance will vary between species depending on the marsupial's requirements, its body size and on the quantity of pollen that is available.
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Marín-Gual, Laia, Laura González-Rodelas, Gala Pujol, Covadonga Vara, Marta Martín-Ruiz, Soledad Berríos, Raúl Fernández-Donoso, et al. "Strategies for meiotic sex chromosome dynamics and telomeric elongation in Marsupials." PLOS Genetics 18, no. 2 (February 7, 2022): e1010040. http://dx.doi.org/10.1371/journal.pgen.1010040.
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During meiotic prophase I, homologous chromosomes pair, synapse and recombine in a tightly regulated process that ensures the generation of genetically variable haploid gametes. Although the mechanisms underlying meiotic cell division have been well studied in model species, our understanding of the dynamics of meiotic prophase I in non-traditional model mammals remains in its infancy. Here, we reveal key meiotic features in previously uncharacterised marsupial species (the tammar wallaby and the fat-tailed dunnart), plus the fat-tailed mouse opossum, with a focus on sex chromosome pairing strategies, recombination and meiotic telomere homeostasis. We uncovered differences between phylogroups with important functional and evolutionary implications. First, sex chromosomes, which lack a pseudo-autosomal region in marsupials, had species specific pairing and silencing strategies, with implications for sex chromosome evolution. Second, we detected two waves of γH2AX accumulation during prophase I. The first wave was accompanied by low γH2AX levels on autosomes, which correlated with the low recombination rates that distinguish marsupials from eutherian mammals. In the second wave, γH2AX was restricted to sex chromosomes in all three species, which correlated with transcription from the X in tammar wallaby. This suggests non-canonical functions of γH2AX on meiotic sex chromosomes. Finally, we uncover evidence for telomere elongation in primary spermatocytes of the fat-tailed dunnart, a unique strategy within mammals. Our results provide new insights into meiotic progression and telomere homeostasis in marsupials, highlighting the importance of capturing the diversity of meiotic strategies within mammals.
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Hayward, John S., and Paul A. Lisson. "Evolution of brown fat: its absence in marsupials and monotremes." Canadian Journal of Zoology 70, no. 1 (January 1, 1992): 171–79. http://dx.doi.org/10.1139/z92-025.
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Species from all extant families of marsupials and monotremes were examined to clarify whether these mammalian subclasses possess brown adipose tissue. To optimize the chance of finding this tissue, special emphasis was given to sampling species adapted to colder regions, species with small adult body size, and individuals at a stage of development equivalent to the newborn stage of placentals (late pouch life in the case of marsupials). Evidence based on gross morphology and light, electron, and fluorescence microscopy failed to show the presence of brown adipose tissue in any marsupial or monotreme. All adipose tissue was typical white fat, including special instances where multilocularity of lipid droplets occurred in association with white adipocyte development or with fat mobilization resulting from nutritional or cold stress. These results, combined with lack of positive identification of brown adipose tissue in birds or other vertebrates, indicate that brown adipose tissue is unique to eutherian (placental) mammals and probably evolved early in the radiation of this subclass. This uniqueness presents the opportunity to suggest a more satisfactory name for the subclass: Thermolipia (from the Greek for "warm fat") or, commonly, thermolipials.
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Munn, Adam J., Peter Banks, and Ian D. Hume. "Digestive plasticity of the small intestine and the fermentative hindgut in a marsupial herbivore, the tammar wallaby (Macropus eugenii)." Australian Journal of Zoology 54, no. 4 (2006): 287. http://dx.doi.org/10.1071/zo06004.
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We investigated the effects of a ground, pelleted diet versus natural forage on the gross morphology of the gastrointestinal tract of a medium-sized (5–7 kg body mass) macropodid marsupial, the tammar wallaby (Macropus eugenii). The empty wet mass (g) of the small intestine of tammar wallabies maintained on a pelleted diet for 6 weeks was 22% greater than that of animals maintained on natural forage, once body mass was taken into account by ANCOVA. Similarly, the body-mass-adjusted length of the tammar wallaby caecum and proximal colon combined was 25% longer in animals maintained on the pelleted diet compared with those maintained on forage. Our data suggest that food particle size may be directly involved in controlling the size of the post-gastric alimentary tract in tammar wallabies, and thus in their diet choice and nutritional ecology. Notably, this is the first study that links phenotypic plasticity of the gut directly to diet in a marsupial and we conclude that the tammar wallaby is an excellent model for exploring the causes and consequences of digestive plasticity in macropodid marsupials.
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Jones, Menna, and Chris Dickman. "Introduction: Carnivorous marsupials." Wildlife Research 28, no. 5 (2001): I. http://dx.doi.org/10.1071/wrv28n5_in.
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Population dynamics and movements were investigated in a population of Pseudantechinus macdonnellensis, a dasyurid marsupial occupying rocky habitats in the Australian arid zone. Intra-annual cycling in abundance, activity and numbers of resident and transient individuals was not regular from year to year, although the number of residents was high compared with the number of transients. Juvenile recruitment varied between years and was as low as 18%. Densities were low (0.05–0.2 ha–1 for females and 0.05–0.3 ha–1 for males), and individuals exhibited large stable long-term ranges – mean Minimum Convex Polygon (MCP) area for males was 427 m2 and for females 171 m2. The constraints of the monoestrous, synchronised reproductive strategy of P. macdonnellensis, together with the ameliorating effect of its rocky habitat, which may decrease food limitation and increase survival, seem to have produced a different pattern of population dynamics to that seen in arid-zone dasyurids that are polyoestrous plains-dwellers. The patterns of movement in P. macdonnellensis also differ from plains-dwelling species, in which individuals display high life-time mobility. The existence of large but non-drifting ranges in P. macdonnellensis may be seen as a consequence of a low but relatively predictable food supply, which precludes the necessity for individuals to shift their activity to temporary patches of high food supply, but requires them to occupy a large range to obtain enough food to meet energy requirements.
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Sankovic, Natasha, Wayne Bawden, John Martyn, Jennifer A. M. Graves, and Kurt Zuelke. "Construction of a marsupial bacterial artificial chromosome library from the model Australian marsupial, the tammar wallaby (Macropus eugenii)." Australian Journal of Zoology 53, no. 6 (2005): 389. http://dx.doi.org/10.1071/zo05033.
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With the accelerating recognition of the power of comparative genomics, there is now enormous interest in sequencing the genomes of a broad range of species. Marsupials diverged at an important evolutionary time. The model Australian marsupial, the tammar wallaby (Macropus eugenii), has long been a resource for biological and genetic studies of marsupials, and the availability of a bacterial artificial chromosome (BAC) library will be a valuable resource in these studies. A tammar wallaby BAC library was constructed using pRazorBAC vector. It contains 55 296 clones with an average insert size of 108 kb, representing 2.2 times coverage of the wallaby genome (based on an estimated 2.7 × 109 bp haploid genome size). The library was arrayed in 384-well plates, and spotted in duplicate onto nylon membranes. Screening these membranes has yielded clones containing 34 single-copy genes distributed over the genome, while it failed for only one gene. Each probe isolated 1–12 BAC clones and, to date, no chimeric clones have been found. This BAC library will constitute an invaluable resource for creating physical maps, positional cloning of genes and other sequences in the tammar wallaby, as well as comparative mapping studies in mammals.
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Frigo, L., and PA Woolley. "Development of the Skeleton of the Stripe-Faced Dunnart, Sminthopsis Macroura (Marsupialia: Dasyuridae)." Australian Journal of Zoology 44, no. 2 (1996): 155. http://dx.doi.org/10.1071/zo9960155.
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Development of the skeleton of the stripe-faced dunnart, Sminthopsis macroura (Gould), a small carnivorous marsupial, was examined in captive-bred pouch young of known age. Skeletal tissue was differentially stained with the dyes alcian blue and alizarin red to demonstrate the presence of cartilage and bone, respectively. The skeleton of the neonate is cartilaginous and ossification centres are first apparent in the skull by Day 5 post partum. The skeleton of S. macroura is well invested with bone by Day 40 of the lactation period, when the young can relinquish the nipple. The sequence of ossification is similar to that reported for other marsupials. Comparisons are made with the eutherian pattern of ossification. This study is the first published work on the ossification of a dasyurid marsupial as shown by whole-mount staining.
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Baudinette, RV. "Locomotion in Macropodoid Marsupials - Gaits, Energetics and Heat-Balance." Australian Journal of Zoology 42, no. 1 (1994): 103. http://dx.doi.org/10.1071/zo9940103.
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This review examines gaits used by marsupials and their coupling with respiratory and cardiac cycles. It also examines the energy requirements and heat balance in exercising marsupials. Marsupials have mass-specific metabolic rates that lie at the lower end of the mammalian range but this is not reflected in locomotory energetics as quadrupedal marsupials fit the Predictive model derived from placentals. The group that does not conform to the model contains the larger hopping macropods in which an independence between metabolic rate and hopping speed is achieved on treadmills at most speeds by the storage of elastic strain energy in tendons. This yields a saving of up to 50% of the energy that would be otherwise used for locomotion. The carriage of pouch young appears to reduce the maximum running speed in quadrupedal marsupials but may be cost-neutral in hopping species. Respiration is entrained to the step cycle in wallabies by means of a visceral piston, but no entrainment of the cardiac cycle has been observed. The consequences of these phenomena are discussed. Marsupials appear to exploit their low body temperatures as a means of storing heat generated during running. Paradoxically, this does not lessen their dependence on evaporative heat loss.
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Cruz, Y. P., H. Morton, A. C. Cavanagh, L. Selwood, S. D. Wilson, and M. Sasaki. "Early pregnancy factor in marsupials." Australian Journal of Zoology 54, no. 3 (2006): 211. http://dx.doi.org/10.1071/zo05050.
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Maternal recognition of pregnancy in marsupials occurs in more subtle ways than it does in eutherians. For instance, unlike in eutherians, the plasma progesterone profiles of pregnant and non-pregnant animals are similar during the luteal phase. It is typically during the brief luteal phase that both gestation and parturition occur in marsupials. Yet histological and physiological changes have been documented between gravid and non-gravid uteri in certain monovular marsupials and between pregnant and non-pregnant animals in polyovular marsupials. Early pregnancy factor (EPF), a 10.8-kDa serum protein known to be homologous to chaperonin 10, is associated with maternal immunosuppression, embryonic development and pregnancy in eutherian mammals. It has been reported in two Australian marsupials: the dasyurid Sminthopsis macroura and the phalangerid Trichosurus vulpecula. This paper documents its occurrence in the New World didelphid Monodelphis domestica. EPF is detectable by rosette inhibition assay in the peripheral circulation of pregnant but not of non-pregnant or pseudopregnant animals. Our work focuses on the embryo–maternal signalling role of EPF during pregnancy. Because progesterone-driven changes are similar in pregnant and non-pregnant marsupials, these animals are an excellent laboratory model in which to investigate the role of EPF in orchestrating the physiological changes necessary to sustain pregnancy.
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Bettiol, Silvana S., Jennifer S. Kettlewell, Norman J. Davies, and John M. Goldsmid. "Giardiasis in Native Marsupials of Tasmania." Journal of Wildlife Diseases 33, no. 2 (April 1997): 352–54. http://dx.doi.org/10.7589/0090-3558-33.2.352.
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Cooper, C. E., and P. C. Withers. "Gross renal morphology of the numbat (Myrmecobius fasciatus) (Marsupialia:Myrmecobiidae)." Australian Mammalogy 32, no. 2 (2010): 95. http://dx.doi.org/10.1071/am10005.
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There is a strong correlation between the structure of the mammalian kidney and its urinary concentrating ability. We examine here the kidney of an endangered termitivorous marsupial (Myrmecobius fasciatus) and use the measured kidney morphometrics to calculate maximal urinary concentration. The relative medullary area (1.34) of the kidney of M. fasciatus is typical of other dasyuromorph marsupials, as is its predicted maximal urinary concentration of 3617 mOsm kg–1 H2O, despite its historically semiarid/arid distribution. The termitivorous diet of M. fasciatus presumably provides it with sufficient water to limit selection for a high urinary concentrating capacity.
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Low, Bobbi S. "Marsupials: Evolutionary Ecology of Marsupials . Anthon K. Lee and Andrew Cockburn. Cambridge University Press, New York, 1985. viii, 274 pp., illus. $54.50. Monographs on Marsupial Biology." Science 232, no. 4746 (April 4, 1986): 111–12. http://dx.doi.org/10.1126/science.232.4746.111.b.
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Low, Bobbi S. "Marsupials: Evolutionary Ecology of Marsupials . Anthon K. Lee and Andrew Cockburn. Cambridge University Press, New York, 1985. viii, 274 pp., illus. $54.50. Monographs on Marsupial Biology." Science 232, no. 4746 (April 4, 1986): 111–12. http://dx.doi.org/10.1126/science.232.4746.111-b.
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