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The use of correct taxonomy to describe and name the earth's biodiversity is fundamental to conservation and management. However, there are issues that need to be overcome to ensure that the described taxa and their scientific names are both appropriate and widely adopted. Obstacles to this include the use of different species definitions, taxonomic instability due to accumulation of additional specimens in analyses and the progression of science that allows better resolution of species boundaries, and the inappropriate description and naming of new taxa without adequate scientific basis in self-published journals (known as 'taxonomic vandalism'). In an effort to manage taxonomic instability, the Australasian Mammal Taxonomy Consortium (AMTC), an affiliated body of the Australian Mammal Society, has developed several tools that include: (1) a standardised list of Australian mammal common and scientific names; (2) recommendations for information that should be included in published species descriptions; and (3) support for the publication of aspidonyms (i.e. a scientifically acceptable name proposed to overwrite a pre-existing unscientific name). This review discusses these issues, reaffirms the foundations for appropriate taxonomic research, and provides guidelines for those publishing taxonomic research on Australian mammals. Correct taxonomy is fundamental to conservation and management. Obstacles to correct taxonomy include the use of different species definitions, taxonomic instability due to accumulation of additional specimens in analyses and the progression of science that allows better resolution of species boundaries, and the inappropriate description and naming of new taxa without adequate scientific basis in self-published journals (known as 'taxonomic vandalism'). The Australasian Mammal Taxonomy Consortium (AMTC), an affiliated body of the Australian Mammal Society, has developed several tools to overcome these issues including: (1) developing a standardised list of Australian mammal common and scientific names; (2) recommending information that should be included in published species descriptions; and (3) supporting for the publication of aspidonyms (i.e. a scientifically acceptable name proposed to overwrite a pre-existing unscientific name). [ABSTRACT FROM AUTHOR]

Maintenance of genetic diversity within species is a key objective of biodiversity conservation, and small, isolated populations are particularly vulnerable to genetic erosion. Conservation management actions such as predator removal, captive breeding and reintroduction can facilitate numerical recovery of a population, but species often remain at risk from depleted genetic diversity and inbreeding. We investigated dispersal, genetic bottlenecks and genetic population structuring in the island‐dwelling Lord Howe woodhen, a species that came perilously close to extinction in the 1970s. Analyses of mark‐resighting records and variable genetic markers (single‐nucleotide polymorphisms) collected from the contemporary population and 100‐year‐old museum specimens found strong evidence of restricted dispersal at fine spatial scales, with both the contemporary and historic populations exhibiting strong population structuring between mountain and lowland/slopes sites. Additionally, genetic comparison of the contemporary population and historic specimens demonstrated a decline in genetic diversity over the past century. Specifically for the Lord Howe woodhen, we recommend ongoing genetic monitoring and translocations to increase genetic diversity within the re‐established lowland subpopulation. More generally, our results demonstrate how pronounced genetic erosion can arise in species subject to human persecution and predation by introduced predators, and how genetic fragmentation of natural populations can be present at fine geographical scales (less than hundreds of metres). Moreover, without prior information about genetic structure and subsequent genetic monitoring, conservation management can have unexpected negative consequences for the genetic health of populations. Therefore, genetic monitoring and management early in the recovery of populations is desirable to maximize their adaptive potential. [ABSTRACT FROM AUTHOR]

Active management is essential to the survival of many threatened species globally. Captive breeding programmes can play an important role in facilitating the supplementation, translocation and reintroduction of wild populations. However, understanding the genetic dynamics within and among wild and captive populations is crucial to the planning and implementation of ex situ management, as adaptive potential is, in part, driven by genetic diversity. Here, we use 14 microsatellite loci and mitochondrial Control Region sequence to examine the population genetics of both wild populations and captive colonies of the endangered warru (the MacDonnell Ranges race of the black-footed rock-wallaby Petrogale lateralis) in central Australia, to understand how historical evolutionary processes have shaped current diversity and ensure effective ex situ management. Whilst microsatellite data reveal significant contemporary differentiation amongst remnant warru populations, evidence of contemporary dispersal and relatively weak isolation by distance, as well as a lack of phylogeographic structure suggests historical connectivity. Genetic diversity within current captive populations is lower than in the wild source populations. Based on our genetic data and ecological observations, we predict outbreeding depression is unlikely and hence make the recommendation that captive populations be managed as one genetic group. This will increase genetic diversity within the captive population and as a result increase the adaptive potential of reintroduced populations. We also identify a new site in the Musgrave Ranges which contains unique alleles but also connectivity with a population 6 km away. This novel genetic diversity could be used as a future source for supplementation. [ABSTRACT FROM AUTHOR]

Habitat loss and fragmentation are key threats to local koala (Phascolarctos cinereus) populations. Broad-scale management is suboptimal for koalas because distribution models are not easily generalised across regions. Therefore, it is imperative that data relevant to local management bodies are available. Genetic data provides important information on gene flow and potential habitat barriers, including anthropogenic disturbances. Little genetic data are available for nationally significant koala populations in north-eastern New South Wales, despite reported declines due to urbanisation and habitat loss. In this study, we develop 14 novel microsatellite loci to investigate koala populations in north-easternNew South Wales (Port Macquarie, Coffs Harbour, Tyagarah, Ballina) and south-eastern Queensland (Coomera). All locations were significantly differentiated (FST = 0.096-0.213; F0 ST = 0.282-0.582), and this pattern was not consistent with isolation by distance (R² = 0.228, P = 0.058). Population assignment clustered the more northern populations (Ballina, Tyagarah and Coomera), suggesting contemporary gene flow among these sites. For all locations, low molecular variation among (16%) rather than within (84%) sites suggests historical connectivity. These results suggest that koala populations in north-eastern NewSouth Wales and south-eastern Queensland are experiencing contemporary impediments to gene flow, and highlight the importance of maintaining habitat connectivity across this region. [ABSTRACT FROM AUTHOR]

Introgressive hybridization has traditionally been regarded as rare in many vertebrate groups, including mammals. Despite a propensity to hybridize in captivity, introgression has rarely been reported between wild sympatric macropodid marsupials. Here we investigate sympatric populations of western (Macropus fuliginosus) and eastern (Macropus giganteus) grey kangaroos through 12 autosomal microsatellite loci and 626 bp of the hypervariable mitochondrial DNA (mtDNA) control region. M. fuliginosus and M. giganteus within the region of sympatry corresponded, both genetically and morphologically, to their respective species elsewhere in their distributions. Of the 223 grey kangaroos examined, 7.6% displayed evidence of introgression, although no F1 hybrids were detected. In contrast to captive studies, there was no evidence for unidirectional hybridization in sympatric grey kangaroos. However, a higher portion of M. giganteus backcrosses existed within the sample compared with M. fuliginosus. Hybridization in grey kangaroos is reflective of occasional breakdowns in species boundaries, occurring throughout the region and potentially associated with variable conditions and dramatic reductions in densities. Such rare hybridization events allow populations to incorporate novel diversity while still retaining species integrity. [ABSTRACT FROM AUTHOR]

In marsupial karyotypes with little heterochromatin, the telomeric sequence (T2AG3)n, is involved in chromosome rearrangements. Here we compare the distribution of the (T2AG3)n sequence in chromosomes recently derived by fusions and other rearrangements (7–0.5 MYBP) with its distribution in chromosomes derived earlier (24–9 MYBP). We have previously shown that the (T2AG3)n sequence is consistently retained during chromosome rearrangements that are recent (7–0.5 MYBP). We suggest that in less recent rearrangements (24–9 MYBP) the pattern observed is initial retention followed by loss or amplification. We also suggest that the presence of interstitial (T2AG3)n sequence is related to the evolutionary status of single chromosomes rather than entire karyotypes. Copyright © 2007 S. Karger AG, Basel [ABSTRACT FROM AUTHOR]

Ecological genetic studies have demonstrated that spatial patterns of mating dispersal, the dispersal of gametes through mating behaviour, can facilitate inbreeding avoidance and strongly influence the structure of populations, particularly in highly philopatric species. Elements of breeding group dynamics, such as strong structuring and sex-biased dispersal among groups, can also minimize inbreeding and positively influence levels of genetic diversity within populations. Rock-wallabies are highly philopatric mid-sized mammals whose strong dependence on rocky terrain has resulted in series of discreet, small colonies in the landscape. Populations show no signs of inbreeding and maintain high levels of genetic diversity despite strong patterns of limited gene flow within and among colonies. We used this species to investigate the importance of mating dispersal and breeding group structure to inbreeding avoidance within a ‘small’ population. We examined the spatial patterns of mating dispersal, the extent of kinship within breeding groups, and the degree of relatedness among brush-tailed rock-wallaby breeding pairs within a colony in southeast Queensland. Parentage data revealed remarkably restricted mating dispersal and strong breeding group structuring for a mid-sized mammal. Breeding groups showed significant levels of female kinship with evidence of male dispersal among groups. We found no evidence for inbreeding avoidance through mate choice; however, anecdotal data suggest the importance of life history traits to inbreeding avoidance between first-degree relatives. We suggest that the restricted pattern of mating dispersal and strong breeding group structuring facilitates inbreeding avoidance within colonies. These results provide insight into the population structure and maintenance of genetic diversity within colonies of the threatened brush-tailed rock-wallaby. [ABSTRACT FROM AUTHOR]

We combine spatial data on home ranges of individuals and microsatellite markers to examine patterns of fine-scale spatial genetic structure and dispersal within a brush-tailed rock-wallaby (Petrogale penicillata) colony at Hurdle Creek Valley, Queensland. Brush-tailed rock-wallabies were once abundant and widespread throughout the rocky terrain of southeastern Australia; however, populations are nearly extinct in the south of their range and in decline elsewhere. We use pairwise relatedness measures and a recent multilocus spatial autocorrelation analysis to test the hypotheses that in this species, within-colony dispersal is male-biased and that female philopatry results in spatial clusters of related females within the colony. We provide clear evidence for strong female philopatry and male-biased dispersal within this rock-wallaby colony. There was a strong, significant negative correlation between pairwise relatedness and geographical distance of individual females along only 800 m of cliff line. Spatial genetic autocorrelation analyses showed significant positive correlation for females in close proximity to each other and revealed a genetic neighbourhood size of only 600 m for females. Our study is the first to report on the fine-scale spatial genetic structure within a rock-wallaby colony and we provide the first robust evidence for strong female philopatry and spatial clustering of related females within this taxon. We discuss the ecological and conservation implications of our findings for rock-wallabies, as well as the importance of fine-scale spatial genetic patterns in studies of dispersal behaviour. [ABSTRACT FROM AUTHOR]

The eukaryotic centromere poses an interesting evolutionary paradox: it is a chromatin entity indispensable to precise chromosome segregation in all eukaryotes, yet the DNA at the heart of the centromere is remarkably variable. Its important role of spindle attachment to the kinetochore during meiosis and mitosis notwithstanding, recent studies implicate the centromere as an active player in chromosome evolution and the divergence of species. This is exemplified by centromeric involvement in translocations, fusions, inversions, and centric shifts. Often species are defined karyotypically simply by the position of the centromere on certain chromosomes. Little is known about how the centromere, either as a functioning unit of chromatin or as a specific block of repetitive DNA sequences, acts in the creation of these types of chromosome rearrangements in an evolutionary context. Macropodine marsupials (kangaroos and wallabies) offer unique insights into current theories expositing centromere emergence during karyotypic diversification and speciation. [ABSTRACT FROM AUTHOR]

Genetic information has played an important role in the development of management units by focusing attention on the evolutionary properties and genetics of populations. Wildlife authorities cannot hope to manage species effectively without knowledge of geographical boundaries and demic structure. The present investigation provides an analysis of mitochondiral DNA and microsatellite data, which is used to infer both historical and contemporary patterns of population structuring and dispersal in the eastern grey kangaroo (Macropus giganteus) in Australia. The average level of genetic variation across sample locations was one of the highest observed for marsupials (h = 0.95, H[SUBE] = 0.82). Contrary to ecological studies, both genic and genotypic analyses reveal weak genetic structure of populations, where high levels of dispersal may be inferred up to 230 km. The movement of individuals was predominantly male-biased (average N[SUBe]m = 22.61, average N[SUBf]m = 2.73). However, neither sex showed significant isolation by distance. On a continental scale, there was strong genetic differentiation and phylogeographic distinction between southern (TAS, VIC and NSW) and northern (QLD) populations, indicating a current and/or historical restriction of gene flow. In addition, it is evident that northern populations are historically more recent, and were derived from a small number of southern founders. Phylogenetic comparisons between M. g. giganteus and M. g. tasmaniensis indicated that the current taxonomic status of these subspecies should be revised as there was a lack of genetic differentiation between the populations sampled. [ABSTRACT FROM AUTHOR]

Despite an increasing appreciation of the disease risks associated with wild-life translocations, the effects which captive breeding programs exert on parasite communities remain understudied. This may be attributed, in part, to the current lack of rapid and cost-effective techniques for comparing parasite assemblages between host populations. Terminal restriction fragment length polymorphism (T-RFLP) analysis of the rDNA region encompassing the internal transcribed spacers (ITS-1 and ITS-2) and 5.8S rRNA gene was used to characterise bursate nematode communities (suborder Strongylida) across two captive and two non-captive colonies of the threatened brush-tailed rock-wallaby, Petrogale penicillata. A clone library was constructed and a restriction enzyme selected to differentiate the predominant operational taxonomic units (OTUs) by the unique peak profiles they generated. The prevalence, intensity of infection and comparative structure of strongylid assemblages was evaluated for each of the host colonies. Compared to wild conspecifics, captive wallabies exhibited a reduced prevalence of infection and significantly lower faecal egg counts. T-RFLP revealed that a high proportion of the OTUs co-occurred across three of the four study locations. Despite this, the composition of strongylid assemblages was significantly different between the colonies, even when host translocation events had occurred. These results suggest that captive breeding programs may exert a profound impact on parasitic helminth assemblages. Developing efficient techniques for characterising community dynamics in potentially pathogenic organisms is critical to the long term success of species recovery efforts worldwide., (Copyright © 2012 Elsevier Inc. All rights reserved.)

The distribution of the conserved vertebrate telomeric sequence (T(2)AG(3))(n) was examined by fluorescence in situ hybridization in the six Petrogale (rock wallabies) taxa of the lateralis complex. As expected, the (T(2)AG(3))(n) sequence was located at the termini of all chromosomes in all taxa. However, the sequence was also present at several nontelomeric (viz., interstitial and centromeric) sites. The signals identified were associated with either ancient rearrangements involved with the formation of the 2n = 22 plesiomorphic macropodine karyotype or more recent rearrangements associated with karyotypes derived from the 2n = 22 karyotype. Interstitial (T(2)AG(3))(n) signals identified on chromosomes 3 and 4 in all six species of the lateralis complex and a large centromeric signal identified on chromosome 7 in the five subspecies/races of P. lateralis appear to be related to the more ancient rearrangements. Subsequent chromosome evolution has seen these signals retained, lost, or amplified in different Petrogale lineages. Within the lateralis complex, in two submetacentric chromosome derived by recent centric fusions, the telomeric sequence was identified at or near the centromere, indicating its retention during the fusion process. In the two taxa where chromosome 3 was rearranged via a recent centromeric transposition to become an acrocentric chromosome, the telomeric signal was located interstitially., (Copyright 2002 S. Karger AG, Basel)