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Andrew M Baker - One of the best experts on this subject based on the ideXlab platform.
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Taxonomy and redescription of the Swamp Antechinus, Antechinus minimus (E. Geoffroy) (Marsupialia: Dasyuridae)
Memoirs of the Queensland museum, 2020Co-Authors: Andrew M Baker, Steve Van DyckAbstract:We provide a taxonomic redescription of the dasyurid marsupial Swamp Antechinus, Antechinus minimus (Geoffroy, 1803). In the past, A. minimus has been classified as two subspecies: the nominate A. minimus minimus (Geoffroy, 1803), which is found throughout much of Tasmania (including southern Bass Strait islands) and A. minimus maritimus (Finlayson, 1958), which is found on mainland Australia (as well as some near-coastal islands) and is patchily distributed in mostly coastal areas between South Gippsland (Victoria) and Robe (South Australia). Based on an assessment of morphology and DNA, we conclude that A. minimus is both distinctly different from all extant congeners and that the two existing subspecies of Swamp Antechinus are appropriately taxonomically characterised. In our genetic phylogenies, the Swamp Antechinus was monophyletic with respect to all 14 known extant congeners; moreover, A. minimus was well-positioned in a large clade, together with all four species in the Dusky Antechinus complex, to the exclusion of all other Antechinus. Within A. minimus, between subspecies there were subtle morphological differences (A. m. maritimus skulls tend to be broader, with larger molar teeth, than A. m. minimus, but these differences were not significant); there was distinct, but only moderately deep genetic differences (3.9–4.5% at mtDNA) between A. minimus subspecies. Comparatively, across Bass Strait, the two subspecies of A. minimus are morphologically and genetically markedly less divergent than recently recognised species pairs within the Dusky Antechinus complex, found in Victoria (A. mimetes) and Tasmania (A. swainsonii) (9.4–11.6% divergent at mtDNA)
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vegetation structure and ground cover attributes describe the occurrence of a newly discovered carnivorous marsupial on the tweed shield volcano caldera the endangered black tailed dusky Antechinus Antechinus arktos
Ecology and Evolution, 2020Co-Authors: Caitlin E Riordan, Andrew M Baker, Coral Pearce, Bill J F Mcdonald, Ian GyntherAbstract:The black-tailed dusky Antechinus (Antechinus arktos) is a recently discovered, endangered, carnivorous marsupial mammal endemic to the Tweed Shield Volcano caldera, straddling the border between Queensland and New South Wales in eastern Australia. The species' preference for cool, high-altitude habitats makes it particularly vulnerable to a shifting climate as these habitats recede. Aside from basic breeding and dietary patterns, the species' ecology is largely unknown. Understanding fine-scale habitat attributes preferred by this endangered mammal is critical to employ successful conservation management. Here, we assess vegetation attributes of known habitats over three sites at Springbrook and Border Ranges National Parks, including detailed structure data and broad floristic assessment. Floristic compositional assessment of the high-altitude cloud rainforest indicated broad similarities. However, only 22% of plant species were shared between all sites indicating a high level of local endemism. This suggests a diverse assemblage of vegetation across A. arktos habitats. Habitat characteristics were related to capture records of A. arktos to determine potential fine-scale structural habitat requirements. Percentage of rock cover and leaf litter were the strongest predictors of A. arktos captures across survey sites, suggesting a need for foraging substrate and cover. Habitat characteristics described here will inform predictive species distribution models of this federally endangered species and are applicable to other mammal conservation programs.
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systematics biogeography and ancestral state of the australian marsupial genus Antechinus dasyuromorphia dasyuridae
Zoological Journal of the Linnean Society, 2019Co-Authors: Thomas Y Mutton, Andrew M Baker, Matthew J Phillips, Susan Fuller, Litticia M BryantAbstract:Since 2012 the number of recognized taxa in the Australian carnivorous marsupial genus Antechinus has increased from 10 to 15 species. The systematic relationships among these species and others in the genus are not well resolved. We undertook the first comprehensive, molecular systematic analysis of the genus, incorporating all known species and subspecies of Antechinus. Two mitochondrial (mtDNA) and four autosomal nuclear genes were sequenced. Four clades of Antechinus were consistently reconstructed in the concatenated and mtDNA analyses: (1) dusky Antechinuses (A. arktos, A. swainsonii, A. vandycki and A. mimetes) and A. minimus; (2) A. godmani; (3) A. agilis, A. stuartii and A. subtropicus; (4) A. argentus, A. mysticus, A. adustus, A. flavipes, A. leo and A. bellus. The inclusion of A. adustus in clade 4 is surprising, because previous morphology-based studies suggested it was a member of clade 3. However, analysis of the nuclear dataset and multi-species coalescence analysis did not separate clades 3 and 4. Within clade 3, A. stuartii is not monophyletic and may be more appropriately classified as two species. Timing of cladogenesis is estimated for all 15 species of Antechinus, permitting us to posit an evolutionary scenario for the group. BEAST analysis dated the divergence of Antechinus from extant congeners to the Late Miocene and cladogenesis among all extant Antechinus to the Plio-Pleistocene. Wet, closed habitat was reconstructed as the most probable ancestral state for the genus Antechinus and the four main Antechinus clades. Overall, increasing aridity from the Miocene to the Pleistocene and a number of well-known biogeographic barriers to mesic species, appear to have driven speciation in Antechinus.
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dietary composition and prey preference of a new carnivorous marsupial species the buff footed Antechinus Antechinus mysticus at the northern and southern limits of its range
Australian Journal of Zoology, 2017Co-Authors: Coral Pearce, Andrew M Baker, Chris J BurwellAbstract:The buff-footed Antechinus (Antechinus mysticus) is a newly described carnivorous marsupial from eastern Australia. We examined the diet composition and prey preference of this little known dasyurid in the southernmost (Brisbane) and northernmost (Eungella) populations. Animals were captured over three months (July–September) during 2014 encompassing the breeding period (late July and August) of the species. Seasonal sampling carried over into a second year which followed the succeeding cohort of juveniles as they dispersed from their maternal nest (summer), through their maturation (autumn), to the beginning of breeding (winter), sampling across one complete generation. The diet of A. mysticus consisted predominantly of invertebrates, with 16 prey orders identified (11 Insecta, two Arachnida, two Myriapoda, one Crustacea). Vertebrate (Family Scincidae) consumption was recorded in low abundance at both sites. The diet of A. mysticus was dominated by Araneae (spiders), Blattodea (cockroaches) and Coleoptera (beetles). Comparison of identified prey consumption in scats with prey availability in pitfall traps showed A. mysticus to be a dietary generalist, opportunistically consuming mostly invertebrate prey with supplementary predation on small vertebrates. Juvenile A. mysticus preyed predominantly on Blattodea (33.4% mean percentage volume) and Coleoptera (31.6% mean percentage volume), potentially suggesting a preference for larger, easier to catch, prey items. Further exploration into the relationship between prey and body size is required to determine this.
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can remote infrared cameras be used to differentiate small sympatric mammal species a case study of the black tailed dusky Antechinus Antechinus arktos and co occurring small mammals in southeast queensland australia
PLOS ONE, 2017Co-Authors: Emma Gray, Todd E Dennis, Andrew M BakerAbstract:The black-tailed dusky Antechinus (Antechinus arktos) is an endangered, small carnivorous marsupial endemic to Australia, which occurs at low population density along with abundant sympatric populations of other small mammals: Antechinus stuartii, Rattus fuscipes and Melomys cervinipes. Using A. arktos as a model species, we aimed to evaluate the effectiveness of infrared digital camera traps for detecting and differentiating small mammals and to comment on the broad applicability of this methodology. We also sought to understand how the detection probabilities of our target species varied over time and characterize their activity patterns. We installed 11 infrared cameras at one of only three known sites where A. arktos occurs for five consecutive deployments. Cameras were fixed to wooden stakes and oriented vertically, 35 cm above ground, directly facing bait containers. Using this method, we successfully recorded and identified individuals from all four species of small mammal known previously in the area from live trapping, including A. arktos. This validates the effectiveness of the infrared camera type and orientation for small mammal studies. Periods of activity for all species were highly coincident, showing a strong peak in activity during the same two-hour period immediately following sunset. A. arktos, A. stuartii and M. cervinipes also displayed a strong negative linear relationship between detection probability and days since deployment. This is an important finding for camera trapping generally, indicating that routine camera deployment lengths (of one-to-two weeks) between baiting events may be too long when targeting some small mammals.
Andrea C Taylor - One of the best experts on this subject based on the ideXlab platform.
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phenotype and gene flow in a marsupial Antechinus flavipes in contrasting habitats
Biological Journal of The Linnean Society, 2008Co-Authors: Hania Lada, Ralph Charles Mac Nally, Andrea C TaylorAbstract:Ecological factors are important drivers of phenotypic divergence, which may lead to incipient speciation. A variety of habitats should be preserved to maintain evolutionary potential. We used the marsupial, the yellow-footed Antechinus (Antechinus flavipes) as a model species for investigating phenotypic differentiation between animals inhabiting two habitat types in south-eastern Australia: flood-plain river red gum and box–ironbark forests. All tested phenotypic characteristics varied between years at the same sites and therefore were not useful for investigating morphological specialization that may lead to speciation. Males generally were significantly heavier when Antechinus densities were lower, but exceptions were found, possibly related to food availability. Teat-number variation recently has been shown to be associated with habitat specialization and incipient speciation within Antechinus agilis. We investigated genetic differentiation associated with this trait in A. flavipes. Population genetic analyses of microsatellite genotypes and mitochondrial DNA haplotypes revealed that sympatric 12-, 13- and 14-teat females in Chiltern forest were part of one freely interbreeding population. Our parentage analyses found two cases where 13-teat mothers produced 12-teat daughters. This suggests either plasticity or paternal genetic influence on the offspring's teat-number phenotype. Laboratory matings may be required to resolve the extent to which teat number is heritable in A. flavipes. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 303–314.
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distinguishing past from present gene flow along and across a river the case of the carnivorous marsupial Antechinus flavipes on southern australian floodplains
Conservation Genetics, 2008Co-Authors: Hania Lada, Ralph Charles Mac Nally, Andrea C TaylorAbstract:Humans have altered many floodplain ecosystems around the world by clearing vegetation, building towns and regulating river flows. Studies discerning gene flow and population structure of floodplain-dwelling animals are rare yet are necessary for understanding the effects of human actions on native populations. In south-eastern Australia, the yellow-footed Antechinus (Antechinus flavipes) is the only carnivorous marsupial on many lowland floodplains, yet our knowledge of impacts of human activities is limited. The control region of mitochondrial DNA and 11 microsatellite DNA markers were used to explore historic and current gene flow in A. flavipes across and along the Murray River. Simulations were carried out to test different migration models. We found evidence for historic gene flow along and across the river but inferred that small towns and farmland or cleared floodplain sections restricted current gene flow along the river. Populations along the river appear to be isolated, and should be maintained at large enough sizes to avoid genetic problems such as inbreeding depression and loss of evolutionary potential. We also investigated whether 50-year-long maintenance of high water levels for irrigation in summer, at the time of juvenile dispersal, has led to restrictions in gene flow across the river. We found no evidence for restrictions to gene flow across the river and suggest that large floods and dropping tree branches may aid dispersal across the river.
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responses of a carnivorous marsupial Antechinus flavipes to local habitat factors in two forest types
Journal of Mammalogy, 2008Co-Authors: Hania Lada, Ralph Charles Mac Nally, Andrea C TaylorAbstract:Abstract Ecosystems around the world have been degraded or destroyed by human activities, including regulation of river flows, clearance of vegetation, and removal of fallen timber. In southeastern Australia much of the original vegetation was converted to farmland. Remaining forests such as hilly box–ironbark and floodplain river red gum (Eucalyptus camaldulensis) are mostly regrowth. The yellow-footed Antechinus (Antechinus flavipes) inhabits both types of forests and is the only small, native, carnivorous mammal on most floodplains in southeastern Australia. In this region, frequency of flooding has been reduced by regulation of river flows, which has led to decline in conditions favorable for flood-adapted terrestrial and aquatic organisms. Here, we compared numbers of A. flavipes in box–ironbark forests, and in river red gum forests that were deprived of floods; partially inundated with environmental flows; flooded naturally; and watered in large, artificial floods. We found that abundance of A. flav...
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genetic reconstruction of the population dynamics of a carnivorous marsupial Antechinus flavipes in response to floods
Molecular Ecology, 2007Co-Authors: Hania Lada, Ralph Charles Mac Nally, Andrea C TaylorAbstract:Human activities such as regulating river flows, logging and removing fallen timber adversely affect floodplain ecosystems around the world. Studies of the dynamics of floodplain-dwelling populations will help to understand the effects of altered flood regimes and to manage and restore floodplains. The yellow-footed Antechinus (Antechinus flavipes) is the only small, native, carnivorous mammal (Marsupialia) on many degraded floodplains in south-eastern Australia, where its abundance appears to increase with proximity to floods, which is partly due to enhanced survival (as inferred from increased abundance of second-year females). We analysed population genetic patterns and maternity among samples collected following the period of postnatal dispersal, in the years preceding and following planned floods, at different distances from flood locations along the Murray River. Our genic and genotypic analyses of mitochondrial DNA (mtDNA) control region haplotypes and 11 microsatellite loci demonstrated high immigration rates into sites in close proximity to floods. All sampled males emigrated from their natal sites to points of capture, while some females were philopatric. There were high rates of dispersal of males among all sites within a partially flooded forest, while females dispersed more to locations closest to inundations rather than to distant places. These results suggest that environmental flows are beneficial to Antechinus both by enhancing adult survival and promoting dispersal of females.
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evaluating simultaneous impacts of three anthropogenic effects on a floodplain dwelling marsupial Antechinus flavipes
Biological Conservation, 2007Co-Authors: Hania Lada, James Robertson Thomson, Ralph Charles Mac Nally, Greg Horrocks, Andrea C TaylorAbstract:Regulation of river flows has altered floodplain ecosystems around the world. Floods are less frequent, which leads to reduction of favourable environmental conditions for many terrestrial and aquatic organisms adapted to natural flooding regimes. In Australia, the Murray River floodplains have been subjected to decline in inundations, to extensive logging and to removal of fallen timber. The yellow-footed Antechinus (Antechinus flavipes) is the only small, native, ground-dwelling/semi-arboreal mammal on most floodplains of south-eastern Australia, yet the effects of floods on its population dynamics largely are unknown. Here, we found positive effects of proximity to flooding, higher woodloads and of abundance of large, hollow-bearing trees on Antechinus numbers. Mean trapping rates of Antechinuses were lowest in 2003 following a 3-year period with no inundation, higher in 2004 following the first breeding season during a small, controlled flood in 2003, and higher again in 2005, following a small, controlled flood in 2004. In 2004 and 2005, trapping rates declined with distance from floodwaters. This study provides evidence for the benefits of using management flows to inundate floodplains, conserving large trees and ensuring high woodloads in floodplains for sustaining populations of the yellow-footed Antechinus.
Peter Templesmith - One of the best experts on this subject based on the ideXlab platform.
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females choose mates based on genetic relatedness in a small dasyurid marsupial the agile Antechinus Antechinus agilis
PLOS ONE, 2015Co-Authors: Marissa L Parrott, Simon J Ward, Peter Templesmith, Lynne SelwoodAbstract:Females in a variety of taxa mate with more than one male during a single oestrus and exhibit mate preferences for genetically compatible males, but the influence of female mate choice on siring success is not clearly understood. Whether females choose to mate with more than one male or endure forced copulations is also often unknown. Here, we examined the effects of genetic relatedness on female mate choice and siring success in a small semelparous carnivorous marsupial, the agile Antechinus (Antechinus agilis), during two consecutive breeding seasons. Experimental trials were conducted in captivity over periods of 72 hours using interconnected enclosures in which female Antechinus could choose to access any of four separated males, but males were only able to access females that entered their quarters. Females had access to two genetically similar and two genetically dissimilar males simultaneously and all behavioural interactions were observed and scored from continuous video recordings. Genetic similarity between mates and paternity of young was determined by microsatellite analyses. Some females chose to enter and mate with more than one male during a single oestrus period. Although females investigated all males, they spent significantly more time visiting, and mated more times with, genetically dissimilar males. Males that were genetically dissimilar to the female sired 88% of subsequent offspring. Whilst males mated readily with most females, they rejected the advances of some receptive females, indicating a previously unexpected level of male mate choice. The results show that genetic relatedness between mates has a significant influence on mate choice, breeding and siring success in the agile Antechinus.
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effects of drought on weight survival and breeding success of agile Antechinus Antechinus agilis dusky Antechinus a swainsonii and bush rats rattus fuscipes
Wildlife Research, 2007Co-Authors: Marissa L Parrott, Simon J Ward, Peter Templesmith, Lynne SelwoodAbstract:Extreme weather conditions, such as drought, significantly decrease the survival and breeding success of numerous species. Despite the frequent occurrence of such conditions in Australia, little is known about the effects of changing environmental conditions on the native small mammals. This study, conducted from 2002 to 2004, focussed on sympatric wild populations of the agile Antechinus (Antechinus agilis), with more limited information on the dusky Antechinus (A. swainsonii) and the bush rat (Rattus fuscipes). Bodyweights of agile Antechinus before and during the breeding season were significantly lower in 2003 (drought) than in 2002 or 2004. Survival of female agile Antechinus and the number of young per litter also decreased significantly during drought. In contrast, the dusky Antechinus showed no difference in mean bodyweights between years, high survival rates of females and similar litter sizes in 2002 and 2003. There was also no difference in bodyweight of bush rats between years. Low rainfall was recorded during pregnancy and lactation in the agile Antechinus, but rainfall was higher during pregnancy and lactation in the dusky Antechinus. The survival and breeding success of the agile Antechinus may have been adversely affected by a combination of interspecific competition, timing of the breeding season and severity of the drought.
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olfactory cues genetic relatedness and female mate choice in the agile Antechinus Antechinus agilis
Behavioral Ecology and Sociobiology, 2007Co-Authors: Marissa L Parrott, Simon J Ward, Peter TemplesmithAbstract:Females show mate preferences for males that are genetically dissimilar to themselves in a variety of taxa, but how females choose these males is not clearly understood. In this study, we examined the effects of olfactory stimuli and genetic relatedness on female mate choice in a small carnivorous marsupial, the agile Antechinus (Antechinus agilis), during two breeding seasons. Captive female Antechinus in oestrus were provided with a combination of male urine and body scent from two novel males, one more genetically similar and one more dissimilar to the females, in a Y-maze olfactometer. Genetic relatedness between females and pairs of males was determined using highly polymorphic, species-specific, microsatellite markers. Females consistently chose to visit the scents of males that were genetically dissimilar to themselves first, spent significantly more time near the source of those scents and showed more sexual and non-exploratory behaviours near those scents. These data demonstrate that chemosensory cues are important in mate choice in the agile Antechinus and that females prefer males that are genetically dissimilar to themselves.
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genetic similarity not male size influences female mate choice in the agile Antechinus Antechinus agilis
Australian Journal of Zoology, 2006Co-Authors: Marissa L Parrott, Simon J Ward, Peter TemplesmithAbstract:Our research investigates the effects of genetic relatedness between mates and male size on female mate choice in the agile Antechinus (Antechinus agilis). Females were provided with a simultaneous choice between one large and one small male, with a minimum 5 g (~20% of male weight) difference between males, in specially designed mate-choice enclosures. Genetic relatedness between males and females was determined using highly polymorphic, species-specific, microsatellite markers. Male size did not influence mate choice, with approximately equal numbers of large and small males chosen. Females chose males that were more genetically dissimilar to themselves significantly more times and showed significantly more sexual and non-exploratory behaviours near the genetically dissimilar males. The results show that, when free female mate choice is possible, female agile Antechinus choose males on the basis of genetic relatedness, rather than male size.
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mating behaviour in the agile Antechinus Antechinus agilis marsupialia dasyuridae
Journal of Zoology, 2002Co-Authors: David A Taggart, G A Shimmin, Peter TemplesmithAbstract:Antechinus agilis mate within a 2–3 week, highly synchronized period each year, with copulation consisting of short bouts of thrusting interrupted by longer bouts of rest during which time the male remains mounted. In the laboratory, mating can last as long as 8–12 h without any break in intromission, with captive paired animals generally copulating once per day (Woolley, 1966a, b). The mating programme used in this study examines the effects on copulatory behaviour of changing: (1) timing of access relative to ovulation; (2) order of mating; (3) the delay between the first and second males' mating access. The total mount time was divided into quarters and the changes in behavioural patterns assessed by examining changes in the frequency of five key activities; thrusting, pelvic side-to-side movements, walking, female resistance, and dismounts. No significant differences were observed in the time from initial pairing to first mount regardless of mating order or time of mating, nor was the total time mounted significantly affected by mating order. Significant reductions in the total time mounted were evident, however, for those males mating closer to the time of ovulation. The behavioural strategies associated with copulation in A. agilis significantly enhance arguments for equality between males and females in determining overall mating strategies.
Hania Lada - One of the best experts on this subject based on the ideXlab platform.
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Decline and potential recovery of Yellow‐footed Antechinus in parts of south‐eastern Australia: A perspective with implications for management
Ecological Management and Restoration, 2008Co-Authors: Hania Lada, Ralph Mac NallyAbstract:Summary The extent and intensity of European-induced changes to ecosystems in south-eastern Australia mean that remaining habitats, despite being degraded, are of high conservation value. Given the extinction of several species of native mammals in the last 160 years in the area, and conservation concerns regarding others, it is important to provide conservation managers with sufficient information to prevent further extinctions and maintain evolutionary potential of the species. A native, carnivorous marsupial, the Yellow-footed Antechinus (Antechinus flavipes) exists within these massively altered landscapes. We present conceptual models, derived from the literature, of persistence of populations of Yellow-footed Antechinus both before European colonization and in the 21st century. We conclude that preservation of large trees, restoration of fallen-timber volumes, spring flooding of floodplains and presence of vegetation corridors between forests should be undertaken to prevent local extinctions of Yellow-footed Antechinus. From historic and current gene flow, we identify remnant woodland and forest groupings that we consider should be managed as coherent units.
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phenotype and gene flow in a marsupial Antechinus flavipes in contrasting habitats
Biological Journal of The Linnean Society, 2008Co-Authors: Hania Lada, Ralph Charles Mac Nally, Andrea C TaylorAbstract:Ecological factors are important drivers of phenotypic divergence, which may lead to incipient speciation. A variety of habitats should be preserved to maintain evolutionary potential. We used the marsupial, the yellow-footed Antechinus (Antechinus flavipes) as a model species for investigating phenotypic differentiation between animals inhabiting two habitat types in south-eastern Australia: flood-plain river red gum and box–ironbark forests. All tested phenotypic characteristics varied between years at the same sites and therefore were not useful for investigating morphological specialization that may lead to speciation. Males generally were significantly heavier when Antechinus densities were lower, but exceptions were found, possibly related to food availability. Teat-number variation recently has been shown to be associated with habitat specialization and incipient speciation within Antechinus agilis. We investigated genetic differentiation associated with this trait in A. flavipes. Population genetic analyses of microsatellite genotypes and mitochondrial DNA haplotypes revealed that sympatric 12-, 13- and 14-teat females in Chiltern forest were part of one freely interbreeding population. Our parentage analyses found two cases where 13-teat mothers produced 12-teat daughters. This suggests either plasticity or paternal genetic influence on the offspring's teat-number phenotype. Laboratory matings may be required to resolve the extent to which teat number is heritable in A. flavipes. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 94, 303–314.
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distinguishing past from present gene flow along and across a river the case of the carnivorous marsupial Antechinus flavipes on southern australian floodplains
Conservation Genetics, 2008Co-Authors: Hania Lada, Ralph Charles Mac Nally, Andrea C TaylorAbstract:Humans have altered many floodplain ecosystems around the world by clearing vegetation, building towns and regulating river flows. Studies discerning gene flow and population structure of floodplain-dwelling animals are rare yet are necessary for understanding the effects of human actions on native populations. In south-eastern Australia, the yellow-footed Antechinus (Antechinus flavipes) is the only carnivorous marsupial on many lowland floodplains, yet our knowledge of impacts of human activities is limited. The control region of mitochondrial DNA and 11 microsatellite DNA markers were used to explore historic and current gene flow in A. flavipes across and along the Murray River. Simulations were carried out to test different migration models. We found evidence for historic gene flow along and across the river but inferred that small towns and farmland or cleared floodplain sections restricted current gene flow along the river. Populations along the river appear to be isolated, and should be maintained at large enough sizes to avoid genetic problems such as inbreeding depression and loss of evolutionary potential. We also investigated whether 50-year-long maintenance of high water levels for irrigation in summer, at the time of juvenile dispersal, has led to restrictions in gene flow across the river. We found no evidence for restrictions to gene flow across the river and suggest that large floods and dropping tree branches may aid dispersal across the river.
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responses of a carnivorous marsupial Antechinus flavipes to local habitat factors in two forest types
Journal of Mammalogy, 2008Co-Authors: Hania Lada, Ralph Charles Mac Nally, Andrea C TaylorAbstract:Abstract Ecosystems around the world have been degraded or destroyed by human activities, including regulation of river flows, clearance of vegetation, and removal of fallen timber. In southeastern Australia much of the original vegetation was converted to farmland. Remaining forests such as hilly box–ironbark and floodplain river red gum (Eucalyptus camaldulensis) are mostly regrowth. The yellow-footed Antechinus (Antechinus flavipes) inhabits both types of forests and is the only small, native, carnivorous mammal on most floodplains in southeastern Australia. In this region, frequency of flooding has been reduced by regulation of river flows, which has led to decline in conditions favorable for flood-adapted terrestrial and aquatic organisms. Here, we compared numbers of A. flavipes in box–ironbark forests, and in river red gum forests that were deprived of floods; partially inundated with environmental flows; flooded naturally; and watered in large, artificial floods. We found that abundance of A. flav...
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genetic reconstruction of the population dynamics of a carnivorous marsupial Antechinus flavipes in response to floods
Molecular Ecology, 2007Co-Authors: Hania Lada, Ralph Charles Mac Nally, Andrea C TaylorAbstract:Human activities such as regulating river flows, logging and removing fallen timber adversely affect floodplain ecosystems around the world. Studies of the dynamics of floodplain-dwelling populations will help to understand the effects of altered flood regimes and to manage and restore floodplains. The yellow-footed Antechinus (Antechinus flavipes) is the only small, native, carnivorous mammal (Marsupialia) on many degraded floodplains in south-eastern Australia, where its abundance appears to increase with proximity to floods, which is partly due to enhanced survival (as inferred from increased abundance of second-year females). We analysed population genetic patterns and maternity among samples collected following the period of postnatal dispersal, in the years preceding and following planned floods, at different distances from flood locations along the Murray River. Our genic and genotypic analyses of mitochondrial DNA (mtDNA) control region haplotypes and 11 microsatellite loci demonstrated high immigration rates into sites in close proximity to floods. All sampled males emigrated from their natal sites to points of capture, while some females were philopatric. There were high rates of dispersal of males among all sites within a partially flooded forest, while females dispersed more to locations closest to inundations rather than to distant places. These results suggest that environmental flows are beneficial to Antechinus both by enhancing adult survival and promoting dispersal of females.
Thomas Y Mutton - One of the best experts on this subject based on the ideXlab platform.
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systematics biogeography and ancestral state of the australian marsupial genus Antechinus dasyuromorphia dasyuridae
Zoological Journal of the Linnean Society, 2019Co-Authors: Thomas Y Mutton, Andrew M Baker, Matthew J Phillips, Susan Fuller, Litticia M BryantAbstract:Since 2012 the number of recognized taxa in the Australian carnivorous marsupial genus Antechinus has increased from 10 to 15 species. The systematic relationships among these species and others in the genus are not well resolved. We undertook the first comprehensive, molecular systematic analysis of the genus, incorporating all known species and subspecies of Antechinus. Two mitochondrial (mtDNA) and four autosomal nuclear genes were sequenced. Four clades of Antechinus were consistently reconstructed in the concatenated and mtDNA analyses: (1) dusky Antechinuses (A. arktos, A. swainsonii, A. vandycki and A. mimetes) and A. minimus; (2) A. godmani; (3) A. agilis, A. stuartii and A. subtropicus; (4) A. argentus, A. mysticus, A. adustus, A. flavipes, A. leo and A. bellus. The inclusion of A. adustus in clade 4 is surprising, because previous morphology-based studies suggested it was a member of clade 3. However, analysis of the nuclear dataset and multi-species coalescence analysis did not separate clades 3 and 4. Within clade 3, A. stuartii is not monophyletic and may be more appropriately classified as two species. Timing of cladogenesis is estimated for all 15 species of Antechinus, permitting us to posit an evolutionary scenario for the group. BEAST analysis dated the divergence of Antechinus from extant congeners to the Late Miocene and cladogenesis among all extant Antechinus to the Plio-Pleistocene. Wet, closed habitat was reconstructed as the most probable ancestral state for the genus Antechinus and the four main Antechinus clades. Overall, increasing aridity from the Miocene to the Pleistocene and a number of well-known biogeographic barriers to mesic species, appear to have driven speciation in Antechinus.
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life history breeding biology and movement in a new species of carnivorous marsupial the buff footed Antechinus Antechinus mysticus and a sympatric congener the subtropical Antechinus Antechinus subtropicus
Mammal Research, 2017Co-Authors: Thomas Y Mutton, Andrew M Baker, Susan Fuller, Emma GrayAbstract:Antechinus are one of just a few mammal genera worldwide which exhibit semelparous reproduction. Consequently, the life history of many Antechinus has been well studied. However, in the last few years, several new species have been described in the genus and their ecology is little known. Here, the first multi-year ecological study of breeding, growth and movement in one of these species, the buff-footed Antechinus, Antechinus mysticus, was undertaken. Over a 2-year period, monthly capture-mark-recapture data from two geographically close sites (~2.5 km apart) in south-east Queensland, Australia, were collected. At one site, the subtropical Antechinus, Antechinus subtropicus, also occurred. This allowed the investigation of possible competitive effects between this larger Antechinus species and A. mysticus. Intensive trapping across the breeding season of A. mysticus also allowed the growth rates of pouch young of a wild Antechinus population to be calculated for the first time. Results showed that A. mysticus followed the synchronous, semelparous breeding strategy seen in all congeners. Male A. mysticus were last caught in August, and females gave birth in September. Average distance moved by A. mysticus was comparable with congeners. Competition with A. subtropicus may affect A. mysticus because A. mysticus weighed more and males moved further when not in sympatry with A. subtropicus. However, female A. mysticus moved further when in sympatry with A. subtropicus, confounding clear interpretation. Overall, the life history information obtained for A. mysticus provides a foundation for further research and will aid the conservation management of this new species.
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evolutionary biology of the australian carnivorous marsupial genus Antechinus
2017Co-Authors: Thomas Y MuttonAbstract:Antechinus is an Australian genus of small carnivorous marsupials. Since 2012, the number of described species in the genus has increased by 50% from ten to fifteen. The systematic relationships of these new species and others in the genus have not been well resolved and a broad phylogeographic study of the genus is lacking. Moreover, little ecological information is known about these new species. Therefore, the present thesis examined the evolutionary biology of Antechinus in two complimentary components. The first component aimed to resolve the systematics and phylogeography of the genus Antechinus. The second component, at a finer spatiotemporal scale, aimed to improve understanding of the autecology, habitat use and risk of extinction within the group, with a focus on the recently named buff-footed Antechinus, A. mysticus and a partially sympatric congener, A. subtropicus.
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a taxonomic assessment of the australian dusky Antechinus complex a new species the tasman peninsula dusky Antechinus Antechinus vandycki sp nov and an elevation to species of the mainland dusky Antechinus Antechinus swainsonii mimetes thomas
Memoirs of the Queensland museum, 2015Co-Authors: Andrew M Baker, Thomas Y Mutton, Eugene D Mason, Emma GrayAbstract:In 2014, the northern outlying population of carnivorous marsupial Dusky Antechinus (Antechinus swainsonii) was nominated a new species, A. arktos. Here, we describe a further new species in the dasyurid A. swainsonii complex, which now contains five taxa. We recognise two distinct species from Tasmania, formerly represented by A. swainsonii swainsonii (Waterhouse); one species (and 2 subspecies) from mainland south-eastern Australia, formerly known as A. swainsonii mimetes (Thomas) and A. swainsonii insulanus Davison; and one species from the Tweed Caldera in mid-eastern Australia, formerly known as A. s. mimetes but recently described as A. arktos Baker, Mutton, Hines and Van Dyck. Primacy of discovery dictates the Tasmanian Dusky Antechinus A. swainsonii (Waterhouse) is nominate; the Mainland Dusky Antechinus taxa, one raised from subspecies within A. swainsonii mimetes (Thomas) is elevated to species (now A. mimetes mimetes) and the other, A. swainsonii insulanus Davison is transferred as a subspecies of A. mimetes (now A. mimetes insulanus); a species from Tasmania, the Tasman Peninsula Dusky Antechinus, is named A. vandycki sp. nov. These taxa are strongly differentiated: geographically (in allopatry), morphologically (in coat colour and craniodental features) and genetically (in mtDNA, 7.5-12.5% between species pairs).
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the black tailed Antechinus Antechinus arktos sp nov a new species of carnivorous marsupial from montane regions of the tweed volcano caldera eastern australia
Science & Engineering Faculty, 2014Co-Authors: Andrew M Baker, Thomas Y Mutton, Harry B Hines, Steve Van DyckAbstract:We describe a new species of dasyurid marsupial within the genus Antechinus that was previously known as a northern outlier of Dusky Antechinus (A. swainsonii). The Black-tailed Antechinus, Antechinus arktos sp. nov., is known only from areas of high altitude and high rainfall on the Tweed Volcano caldera of far south-east Queensland and north-east New South Wales, Australia. Antechinus arktos formerly sheltered under the taxonomic umbrella of A. swainsonii mimetes, the widespread mainland form of Dusky Antechinus. With the benefit of genetic hindsight, some striking morphological differences are herein resolved: A. s. mimetes is more uniformly deep brown-black to grizzled grey-brown from head to rump, with brownish (clove brown—raw umber) hair on the upper surface of the hindfoot and tail, whereas A. arktos is more vibrantly coloured, with a marked change from greyish-brown head to orange-brown rump, fuscous black on the upper surface of the hindfoot and dense, short fur on the evenly black tail. Further, A. arktos has marked orange-brown fur on the upper and lower eyelid, cheek and in front of the ear and very long guard hairs all over the body; these characters are more subtle in A. s. mimetes. There are striking genetic differences between the two species: at mtDNA, A. s. mimetes from north-east New South Wales is 10% divergent to A. arktos from its type locality at Springbrook NP, Queensland. In contrast, the Ebor A. s. mimetes clades closely with conspecifics from ACT and Victoria. A. arktos skulls are strikingly different to all subspecies of A. swainsonii. A. arktos are markedly larger than A. s. mimetes and A. s. swainsonii (Tasmania) for a range of craniodental measures. Antechinus arktos were historically found at a few proximate mountainous sites in south-east Queensland, and have only recently been recorded from or near the type locality. Even there, the species is likely in low abundance. The Black-tailed Antechinus has plausibly been detrimentally affected by climate change in recent decades, and will be at further risk with increasing warming trends.
