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Novel insights into the phylogenetic relationships of the endangered marsupial genus Potorous
Supplementary resources (80)
Nucleotide Sequence
May 2012
Nucleotide Sequence
May 2012
Nucleotide Sequence
May 2012
... Recent genetic studies by Frankham et al., (2012;2016) examined the phylogeography of the Long-nosed Potoroo across its range. These studies identified Bass Strait as a major biogeographic barrier within the species, suggesting that gene flow between mainland Australia and Tasmanian populations last occurred around 2.45 million years ago. ...
... Sequences were visually checked with reference to chromatograms using Sequencher version 5.2.4. Sequence alignments were carried out in Mega version 6 with comparison to CO1 and ND2 fragments generated by Frankham et al. (2012) (GenBank Accession numbers CO1: JX111894-JX111903 and ND2 JX104566-JX104576), CO1 and ND2 sequences from the common wallaroo, Osphranter robustus (GenBank accession number Y10524) were used as outgroups. Phylogenetic relationships were estimated using both Bayesian inference (BI) and maximum likelihood (ML). ...
... Although only partial fragments (695 bp of CO1 [n = 4] and 344 bp of ND2 [n = 2]) were available for analysis, these data consistently placed the individuals from both King and Flinders Islands within the Tasmanian subspecies Potorous tridactylus apicalis. The topology of the phylogenetic trees generated in this study were concordant with those describing three divergent potoroo subspecies generated by Frankham et al. (2012) who examined a longer mtDNA fragment of 2103 bp of CO1 and ND2 from 11 potoroo samples, as well as 1893 bp of nuDNA. These subspecies were Potorous tridactylus tridactylus (distributed in New South Wales north of Sydney and in southeast Queensland), Potorous tridactylus trisulcatus (New South Wales south of Sydney, plus Victorian and South Australian populations) and Potorous tridactylus apicalis (Tasmanian populations). ...
Bass Strait is an important biogeographic barrier for Australian mammals, often resulting in significant genetic differentiation between populations on the mainland and Tasmania for species with a trans-Bassian distribution. King and Flinders Islands, in Bass Strait, are the largest remnants of the land bridge that once linked Tasmania with mainland Australia. Due to their remote locality and habitat loss on the islands since European settlement, little is known about the evolutionary movements of species across the former land bridge. Here we present genetic data, generated from museum skins, on the King and Flinders Island populations of Long-nosed Potoroo, Potorous tridactylus (Kerr, 1792) to investigate their affinities with other populations of this species. We also assessed the validity of the subspecies Potorous tridactylus benormi Courtney, 1963 described from King Island. Analysis of two partial mitochondrial DNA genes (CO1, ND2) indicate that potoroos on King and Flinders Islands are more closely related to Tasmanian rather than mainland potoroo populations. Molecular and morphological data from the holotype and paratype of Potorous tridactylus benormi does not support separate taxonomic status and places it within the Tasmanian subspecies Potorous tridactylus apicalis (Gould, 1851). © 2020 Frankham, Neaves, Eldridge. This is an open access article licensed under a Creative Commons Attribution 4.0 International License (CC BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original authors and source are credited.
... Likewise for the putative taxa Hypsiprymnus apicalis Gould, 1851 from New Norfolk, Tasmania and H. trisulcatus McCoy, 1865 based on a type from near Gisborne, Victoria. Frankham et al. (2012) published a phylogeny for the putative species P. tridactylus including specimens from across the known range and found significant divergences between the populations. They found putative P, gilberti diverged from the (south) eastern populations 5.77 MYA and 7.2 MYA from those from the New South Wales (NSW) Central Coast and further north (a total of two main identified groups). ...
... In order to resolve this clear error of assignment, one must either transfer both putative subspecies to the synonymy of P, gilberti and continue to regard each as subspecies, or in the alternative, and based on quoted divergences, simply elevate all to full species, which in the absence of evidence to the contrary would be the most sensible outcome. In terms of the remainder of putative P. tridactylus, Frankham et al. (2012) found a divergence between two main groups of 1.32 MYA, which is again a species-level divergence. With the northern group unnamed, it again seemed logical to name that as a new species to enable proper conservation measures to take place and allow zoologists to do proper studies involving known taxa as opposed to directly transposing potentially misleading results from other taxa to it. ...
... Live and dead specimens as well as available bone specimens, were examined as was other relevant material, including past climate data for the applicable regions, sea level depths and other relevant information. In summary, as inferred already, the results of Frankham et al. (2012) as interpreted and corrected in the introduction stood up to scrutiny. Therefore P. tridactylus as currently recognized is herein split into four species, as well as the sometimes separately recognized species P. gilberti, making a total of five. ...
ABSTRACT
Potoroos within the family Potoroidae are small marsupials which were abundant at the time Europeans first
came to Australia (White and Stone 1790).
They have severely declined in number since.
Three main species groups, all currently placed in the genus Potorous Desmarest, 1804 (type species
Didelphis tridactyla Kerr, 1792) have been formally described and named, containing one putative species
each based on most recently published classifications.
One of these, the Long-nosed Potoroo Potorous tridactylus (Kerr, 1792) was recently subdivided into two
species, namely P. gilberti (Gould, 1841) from Western Australia and P. tridactylus from eastern Australia,
treated as consisting three subspecies, being the nominate form from the Central Coast of New South Wales,
P. tridactylus apicalis (Gould, 1851) from Tasmania and P. tridactylus trisulcatus (McCoy, 1865) from Victoria
(Frankham et al. 2012).
Molecular studies have shown east Australian P. tridactylus to consist of four main divergent clades and so
the unnamed one is formally named in this paper as P. waddahyamin sp. nov. based on well-known
morphological divergences.
Each of the four clades are also formally elevated to full species based on known dates of divergence being
1.32 and 2.45 MYA from nearest common ancestor.
Of the three main species groups within the putative genus Potorous two have generic names available being
Potorous and Potoroops Matschie, 1916 for the type species Hypsiprymnus platyops Gould, 1844. The third
species group does not. As the molecular studies of Westerman et al. (2004) and Frankham et al. (2012)
showed genus-level divergences between the groups, the unnamed one is formally named for the first time.
The species Potorous longipes Seebeck and Johnston, 1980 is formally placed in the new genus
Rossignolius gen. nov..
Keywords: Taxonomy; nomenclature; classification; Potoroo; Marsupials; Potoroidae; Potorous;
Potoroops; Hypsiprymnus; platyops; tridactylus; trisulcatus; gilberti; apicalis; longipes; New genus;
Rossignolius; new species; waddahyamin.
... A recent multi-locus sequencing study identified three highly divergent lineages within P. tridactylus (Frankham et al., 2012): a northern mainland, P. t. tridactylus (Kerr, 1792) and southern mainland lineage, P. t. trisulcatus (McCoy 1865) and a Tasmanian lineage, P. t. apicalis (Gould, 1851). While the sampling of Frankham et al. (2012) encompassed much of the range of P. tridactylus, it was limited (n = 11 individuals), and provided only approximate locations of the phylogeographical breaks between lineages. ...
... A recent multi-locus sequencing study identified three highly divergent lineages within P. tridactylus (Frankham et al., 2012): a northern mainland, P. t. tridactylus (Kerr, 1792) and southern mainland lineage, P. t. trisulcatus (McCoy 1865) and a Tasmanian lineage, P. t. apicalis (Gould, 1851). While the sampling of Frankham et al. (2012) encompassed much of the range of P. tridactylus, it was limited (n = 11 individuals), and provided only approximate locations of the phylogeographical breaks between lineages. With its distribution, P. tridactylus is likely to have been impacted by population fragmentation caused by past climatic oscillations, as well as more recent anthropogenic change. ...
... Potorous tridactylus haplotypes formed three reciprocally monophyletic and highly divergent lineages corresponding to discreet geographical regions (Fig. 2). These were congruent with the subspecies delineations proposed by Frankham et al. (2012). Two lineages were present on the Australian mainland, with haplotypes from northern NSW (north of Sydney, approximately 33°S) and southern Queensland forming one lineage (northern mainland lineage), and haplotypes from southern NSW (south of Sydney, approximately, 34°S) and Victoria forming a second (southern mainland lineage). ...
Aim
Outside of Australia's Wet Tropics, studies of the biogeographical patterns of unglaciated Southern Hemisphere mesic environments are limited, and have primarily focused on herpetofauna. In this study mitochondrial DNA (mt DNA ) and microsatellite (nu DNA ) analyses were used to investigate the impact of biogeographical barriers on the evolutionary history of the widespread Australian marsupial Potorous tridactylus , as well as the effect of recent human‐mediated habitat fragmentation.
Location
Australia; Queensland, New South Wales, Victoria, and Tasmania.
Methods
Three hundred and fifty‐four individuals from 39 sites (representing 16 regional populations) across the species range were assessed for mt DNA Control Region and microsatellite (10 loci) variation. Genetic diversity, phylogeographical relationships and population structure were examined, as well as evidence for isolation by distance and past population expansion.
Results
Three highly divergent and reciprocally monophyletic mt DNA lineages were resolved (two mainland, one Tasmanian). A deep phylogeographical break, not associated with any obvious biogeographical barrier, was present on the mainland. Within the northern mainland and Tasmanian lineages, sub‐structuring was coincident with the presence of physical barriers to gene flow. Fine‐scale structuring was also present, with regional populations highly differentiated.
Main conclusions
This study expands on previous studies of Australia's mesic biome. Major phylogeographical breaks were identified, that dated to the Miocene (within the mainland) and Pliocene (isolation of Tasmanian), and differed from those described for the region's herpetofauna in age or location. The major mainland break appears species specific within this topographically complex region of Australia. Tasmanian populations were isolated from the mainland well before the most recent flooding of Bass Strait. Minor phylogenetic breaks within Tasmanian and northern NSW were associated with known biogeographical barriers. An absence of sub‐structuring within the southern mainland lineage suggests extensive historical connectivity. The presence of regional population structure suggests that post‐European settlement, local populations have become isolated and differentiated.
... However, Paplinska et al. (2011) used museum specimens to extend the known range of the Central lineage to south of the ACT (Fig 1). While no obvious north-south barrier to gene flow occurs in this region, it is emerging as the location of major phylogenetic breaks within a variety of vertebrate species including lizards (Chapple et al. 2005(Chapple et al. , 2011a, mammals (Frankham et al. 2012), frogs (Schauble and Moritz 2001;Symula et al. 2008), and as a contact zone between sibling species (e.g., Dickman et al. 1988;Donnellan et al. 1999;Lindenmayer et al. 2002;Burns and Crayn 2006). This geographically coincident phylogenetic break in a variety of taxa strongly suggests a common underlying cause. ...
... The clustering of populations with respect to the three identified mtDNA lineages is indicated by shading: red, Northern lineage; blue, Central lineage; and yellow, Southern lineage. older and deeper (Pliocene-Miocene) than those reported here for brush-tailed rock-wallabies (mid-Pliestocene), reinforcing the long-term impacts of these barriers on the fauna of southeastern Australia (Chapple et al. 2005(Chapple et al. , 2011aSymula et al. 2008;Frankham et al. 2012). ...
... This suggests that in this region multiple small-scale refugia existed during less severe glacial cycles. Similar patterns of substructuring north and south of the Clarence River Valley are seen in the codistributed longnosed potoroo (Potorous tridactylus) (Frankham et al. 2012) and Hastings River mouse (Pseudomys oralis) (Rowe et al. 2011), providing evidence for the existence of "refugia within refugia" in this region. ...
Mesic southeastern Australia represents the continent's ancestral biome and is highly biodiverse, yet its phylogeographic history remains poorly understood. Here, we examine mitochondrial DNA (mtDNA) control region and microsatellite diversity in the brush-tailed rock-wallaby (Petrogale penicillata;n = 279 from 31 sites), to assess historic evolutionary and biogeographic processes in southeastern Australia. Our results (mtDNA, microsatellites) confirmed three geographically discrete and genetically divergent lineages within brush-tailed rock-wallabies, whose divergence appears to date to the mid-Pleistocene. These three lineages had been hypothesized previously but data were limited. While the Northern and Central lineages were separated by a known biogeographic barrier (Hunter Valley), the boundary between the Central and Southern lineages was not. We propose that during particularly cool glacial cycles, the high peaks of the Great Dividing Range and the narrow adjacent coastal plain resulted in a more significant north-south barrier for mesic taxa in southeastern Australia than has been previously appreciated. Similarly, located phylogeographic breaks in codistributed species highlight the importance of these regions in shaping the distribution of biodiversity in southeastern Australia and suggest the existence of three major refuge areas during the Pleistocene. Substructuring within the northern lineage also suggests the occurrence of multiple local refugia during some glacial cycles. Within the three major lineages, most brush-tailed rock-wallaby populations were locally highly structured, indicating limited dispersal by both sexes. The three identified lineages represent evolutionarily significant units and should be managed to maximize the retention of genetic diversity within this threatened species.
... Our maximum likelihood, Bayesian and time-tree analyses of the nDNA (Supplementary Figures S7-S9) and combined mitogenome/mtDNA/nDNA datasets ( Fig. 2; Supplementary Figures S10-S12) yield broadly compatible topologies, with the basal divergence of potoroids and macropodids, and subsequent split between potoroines and bettongines both occurring from the latest Oligocene to earliest-middle Miocene ( Table 2; Supplementary Table S7). Notably, this concurs with divergence times derived using different dating methods and constraints 12,[46][47][48][49][50]56 . Furthermore, while our BioGeoBEARS and BBM ancestral range estimations correlate the latest Eocene (or mid-Eocene using nDNA: Supplementary Table S7) The globally recognised 58 middle to late Miocene climatic transition from equable to increasingly cool, dry conditions 41,59 coincides with potoroine speciations into mesic environments throughout southern Australia 27,56 . ...
... Notably, this concurs with divergence times derived using different dating methods and constraints 12,[46][47][48][49][50]56 . Furthermore, while our BioGeoBEARS and BBM ancestral range estimations correlate the latest Eocene (or mid-Eocene using nDNA: Supplementary Table S7) The globally recognised 58 middle to late Miocene climatic transition from equable to increasingly cool, dry conditions 41,59 coincides with potoroine speciations into mesic environments throughout southern Australia 27,56 . These are tracked by our BioGeoBEARS and BBM estimates, which infer occupation of primarily woodland and forest habitats after the earliest-late Miocene (Supplementary Tables S7-S9; Supplementary Figures S13 and S14). ...
The evolution of Australia’s distinctive marsupial fauna has long been linked to the onset of continent-wide aridity. However, how this profound climate change event affected the diversification of extant lineages is still hotly debated. Here, we assemble a DNA sequence dataset of Macropodoidea—the clade comprising kangaroos and their relatives—that incorporates a complete mitogenome for the Desert ‘rat-kangaroo’, Caloprymnus campestris . This enigmatic species went extinct nearly 90 years ago and is known from a handful of museum specimens. Caloprymnus is significant because it was the only macropodoid restricted to extreme desert environments, and therefore calibrates the group’s specialisation for increasingly arid conditions. Our robustly supported phylogenies nest Caloprymnus amongst the bettongs Aepyprymnus and Bettongia . Dated ancestral range estimations further reveal that the Caloprymnus - Bettongia lineage originated in nascent xeric settings during the middle to late Miocene, ~ 12 million years ago (Ma), but subsequently radiated into fragmenting mesic habitats after the Pliocene to mid-Pleistocene. This timeframe parallels the ancestral divergences of kangaroos in woodlands and forests, but predates their adaptive dispersal into proliferating dry shrublands and grasslands from the late Miocene to mid-Pleistocene, after ~ 7 Ma. We thus demonstrate that protracted changes in both climate and vegetation likely staged the emergence of modern arid zone macropodoids.
... Our maximum likelihood, Bayesian and time-tree analyses of the nDNA (Supplementary Figures S7-S9) and combined mitogenome/mtDNA/nDNA datasets (Figure 2; Supplementary Figures S10-S12) yield broadly compatible topologies, with the basal divergence of potoroids and macropodids, and subsequent split between potoroines and bettongines both occurring during the early Miocene (Table 2; Supplementary Table S4). Notably, this concurs with divergence estimates derived using different dating methods and constraints 12,[42][43][44][45][46]52 . Furthermore, while our S-DIVA and BBM ancestral area optimisations correlate the early Oligocene (or late Eocene based on nDNA 41 ; Supplementary Table S4) Figures S13 and S14). ...
... tridactylus trisulcatus with P. gilbertii (2.69/5%), P. platyops (4.1/5%), and P. longipes (5.84/5.69%), supporting inferences of cryptic taxa 52 Figures S13 and S14), followed by a Pliocene to as recent as middle Pleistocene radiation of B. gaimardi + B. tropica + B. penicillata subsp. (Table 2; Supplementary Table S5) in conjunction with mesic habitat variegation ( Supplementary Figures S13 and S14). ...
The evolution of Australia’s distinctive marsupial fauna has long been linked to the onset of continent-wide aridity. However, how this profound climate change event affected the diversification of extant lineages is still hotly debated. Here, we assemble a DNA sequence dataset of Macropodoidea — the clade comprising kangaroos and their relatives — that incorporates a complete mitogenome for the Desert ‘rat-kangaroo’, Caloprymnus campestris. This enigmatic species went extinct nearly 90 years ago and is known from a handful of museum specimens. Caloprymnus is significant because it was the only macropodoid restricted to extreme desert environments, and therefore calibrates the group’s specialisation for increasingly xeric conditions. Our robustly supported phylogenies nest Caloprymnus amongst the bettongs Aepyprymnus and Bettongia. Dated ancestral area optimisations further reveal that the Caloprymnus-Bettongia lineage originated in nascent arid zone settings from the later-middle to early-late Miocene, ~12 million years ago (Ma), but subsequently dispersed into mesic habitats during the Pliocene and Pleistocene. This coincides with ancestral divergences amongst kangaroos in disparate woodland-forest and shrubland settings, but predates their adaptive radiation into proliferating grasslands during the late Miocene to Pliocene, after ~7 Ma. We thus demonstrate that protracted changes in both climate and vegetation likely staged the emergence of modern arid zone macropodoids.
... Generally, the longer populations are separated, the more substitutions they will accumulate, until eventually they become different enough to be considered different species (Bromham 2008). Notwithstanding this, recent recommendations favour the application of the biological species concept in conservation biology, or its extension: the differential fitness species concept (Frankham et al. 2012). Therefore, the point at which two populations can no longer interbreed should clearly delineate divergent speciation (Mayr 2000). ...
... Therefore, the point at which two populations can no longer interbreed should clearly delineate divergent speciation (Mayr 2000). The status of the taxa that comprise genus Potorous has also been debated, complicating the conservation management decision-making process (Frankham et al. 2012). Previous studies have suggested breeding potoroos from certain populations (i.e. ...
The three surviving ‘brush-tailed’ bettong species—Bettongia gaimardi (Tasmania), B. tropica (Queensland) and B. penicillata (Western Australia), are all classified as threatened or endangered. These macropodids are prolific diggers and are recognised as important ‘ecosystem engineers’ that improve soil quality and increase seed germination success. However, a combination of introduced predators, habitat loss and disease has seen populations become increasingly fragmented and census numbers decline. Robust phylogenies are vital to conservation management, but the extent of extirpation and fragmentation in brush-tailed bettongs is such that a phylogeny based upon modern samples alone may provide a misleading picture of former connectivity, genetic diversity and species boundaries. Using ancient DNA isolated from fossil bones and museum skins, we genotyped two mitochondrial DNA (mtDNA) genes: cytochrome b (266 bp) and control region (356 bp). These ancient DNA data were combined with a pre-existing modern DNA data set on the historically broadly distributed brush-tailed bettongs (~300 samples total), to investigate their phylogenetic relationships. Molecular dating estimates the most recent common ancestor of these bettongs occurred c. 2.5 Ma (million years ago), which suggests that increasing aridity likely shaped their modern-day distribution. Analyses of the concatenated mtDNA sequences of all brush-tailed bettongs generated five distinct and well-supported clades including: a highly divergent Nullarbor form (Clade I), B. tropica (Clade II), B. penicillata (Clades III and V), and B. gaimardi (Clade IV). The generated phylogeny does not reflect current taxonomy and the question remains outstanding of whether the brush-tailed bettongs consisted of several species, or a single widespread species. The use of nuclear DNA markers (single nucleotide polymorphisms and/or short tandem repeats) will be needed to better inform decisions about historical connectivity and the appropriateness of ongoing conservation measures such as translocations and captive breeding.
... Tissue samples were collected from two subpopulations within three regional populations of the P. tridactylus subspecies, P. tridactylus trisulcatus (Frankham et al. 2012): Southern Highlands (SH), in New South Wales, as well as East Gippsland (EG) and French Island (FI) both in Victoria (Fig. 1). The SH subpopulations were managed as part of the Budderoo National Park and Barren Grounds Nature Reserve. ...
... This would also promote population longevity through providing adaptive potential to buffer against future climatic changes or stochastic events (Willi et al. 2006). Phylogenetic research carried out by Frankham et al. (2012) suggests all Victorian and southern New South Wales P. tridactylus populations (including SH) comprise the same subspecies. While there are many factors to consider in translocating individuals between populations, the risk of out-breeding depression does not be appear to be a limiting factor if movement of individuals was carried out within this subspecies (Frankham et al. 2011b). ...
Fine-scale genetic structure was investigated in three regional populations of the long-nosed potoroo (Potorous tridactylus) a threatened endemic marsupial. Two populations were from the Australian mainland and one from an island. Populations were sub-sampled at two sites, 6–8 km apart, connected by suitable habitat for dispersal. Factors influencing fine-scale structure were investigated by genotyping 157 individuals at 10 microsatellite loci and sequencing a ~621 bp region of the mtDNA control region. Results indicated that P. tridactylus populations exhibit significant intra-population structure, with significant F
ST
and Φ
ST
values recorded between subpopulations. This structure appeared mediated by small neighbourhood size, female philopatry and limited dispersal over 6–8 km, predominantly by males. Results highlighted several important features of P. tridactylus populations that have implications for conservation. Firstly, the small neighbourhood size suggests any investigations of intra-population structure should be conducted on a finer scale (e.g. 25–50 m) than many current monitoring programs. Secondly, the island populations were genetically depauperate, which may reflect processes occurring in many isolated ‘mainland island’ populations. Thirdly, the lower gene flow identified between populations separated by anthropogenically modified habitat suggests P. tridactylus is sensitive to changes in habitat configuration.
... For any species found in the ALA list that were not yet represented in the 12S database, we searched GenBank (The National Center for Biotechnology Information (NCBI); https://www.ncbi.nlm.nih.gov/genbank) for representative 12S sequences and, if available, added them to our reference set. We thus supplemented Modave's dataset with a further 31 marsupial (Springer and Douzery 1994;Krajewski et al. 1997;Westerman et al. 1999 Frankham et al. 2012;Westerman et al. 2012;Phillips et al. 2013;Mitchell et al. 2014;Nilsson et al. 2018), as well as five domestic dog (Webb and Allard 2009;Matsumura et al. 2014), seven deer (Ramón-Laca et al. 2014), and 16 dingo sequences (Cairns and Wilton 2016). All sequences used in our reference dataset are available at https://github.com/ ...
Context Accurate monitoring data on species presence and distribution are crucial for effective conservation management. Environmental DNA (eDNA)-based techniques, in which species are detected from trace amounts of DNA found throughout the environment, are promising tools that may complement traditional monitoring methods and improve detection. However, imperfect detection is a feature of all survey methods that should be properly assessed so that the probability of detecting a target species’ DNA at a site where it is present (i.e. the sensitivity of the method) can be determined. The spot-tailed quoll (Dasyurus maculatus), a carnivorous marsupial found in eastern Australia, is a difficult species to detect as it is rare and has large home ranges, often in remote and difficult to access habitat. Aims In this study, we aimed to evaluate the feasibility of using eDNA soil analysis as a viable alternative or complement to traditional monitoring techniques for detecting spot-tailed quoll. Methods We developed a species-specific assay and validated it using synthetic oligos, tissue samples and soil collected from a captive quoll enclosure. We then assessed the assay on natural environment soil samples taken from the Snowy River region from communal quoll defecation sites (latrines) and from broader quoll habitat. We used amplification success data to model the concentration of quoll DNA in soil from different site types and calculate the sensitivity of our assay. Key results Sensitivity was highest at latrine sites, but decreased sharply when sampling just 1 m away. In non-latrine habitat, the positive amplification rate was too low to allow for meaningful statistical analyses, suggesting that a prohibitively large number of samples would need to be analysed for detection probabilities to be adequate for routine monitoring programs. Conclusions Overall, we found that low sensitivity was driven by the low concentration of spot-tailed quoll DNA at many of the surveyed sites. Implications Given that quoll latrines can usually be identified from the accumulation of scats, and scats themselves can be sampled for DNA, we suggest that eDNA analysis of soil is unlikely to offer improvements over current spot-tailed quoll monitoring methods.
... The taxonomy of the remaining potoroo species, however, remains unsettled. Potorous gilbertii was recently raised from synonymy (Sinclair et al. 1996); however, P. gilbertii mitochondrial DNA appears paraphyletic with P. tridactylus (Frankham et al. 2012). Potorous tridactylus is the most widely distributed Potorous species, along the east coast of Australia and throughout Tasmania, and significant morphological variation is present across the species' range, as well as large genetic divergences in both nuclear and mitochondrial DNA. ...
... The taxonomy of the remaining potoroo species, however, remains unsettled. Potorous gilbertii was recently raised from synonymy (Sinclair et al. 1996); however, P. gilbertii mitochondrial DNA appears paraphyletic with P. tridactylus (Frankham et al. 2012). Potorous tridactylus is the most widely distributed Potorous species, along the east coast of Australia and throughout Tasmania, and significant morphological variation is present across the species' range, as well as large genetic divergences in both nuclear and mitochondrial DNA. ...
... The taxonomy of the remaining potoroo species, however, remains unsettled. Potorous gilbertii was recently raised from synonymy (Sinclair et al. 1996); however, P. gilbertii mitochondrial DNA appears paraphyletic with P. tridactylus (Frankham et al. 2012). Potorous tridactylus is the most widely distributed Potorous species, along the east coast of Australia and throughout Tasmania, and significant morphological variation is present across the species' range, as well as large genetic divergences in both nuclear and mitochondrial DNA. ...
... The nearest recent records are from Barren Grounds NR in 2010 and Mangrove Mountain in 2004 (OEH 2012b). One or both of two subspecies may have occurred in the WHA: the northern mainland subspecies tridactylus and the southern mainland subspecies trisulcatus (Frankham et al. 2012). ...
The Greater Blue Mountains World Heritage Area covers over 1,000,000 ha and comprises eight reserves: Blue Mountains, Gardens of Stone, Kanangra-Boyd, Nattai, Thirlmere Lakes, Wollemi and Yengo National Parks, and Jenolan Karst Conservation Reserve. The area was inscribed on the World Heritage List in 2000 because its natural values, including the diversity of its fauna, were considered to be outstanding at international level. For this list of its fauna, we have used the current boundaries of the eight reserves, including additions to the reserves since their inscription on the World Heritage List, even though the additions are not yet officially part of the World Heritage Area. The additions total about 40,000 ha.
In 1998, when the nomination of the Greater Blue Mountains Area for inscription on the World Heritage List was prepared for the Australian Government, it was well known that the area provided habitat for a wide variety of mammals, birds, reptiles and frogs but the details were sketchy. The nomination indicated that about 400 native terrestrial vertebrate fauna species had been recorded in the area, including 52 mammal, 265 bird, 63 reptile and more than 30 frog species. However, these included species recorded in the vicinity but not confirmed to occur within the World Heritage Area.
We have been residents of the Blue Mountains, and have observed and kept records of its fauna, for over 40 years. As ecological consultants, we have carried out many fauna surveys in the area. In 1990, we published a book on the local fauna (J. Smith and P. Smith, 1990, Fauna of the Blue Mountains, Kangaroo Press, Kenthurst) and in 2019, from our own records and many other sources, we published a more comprehensive book on the fauna of the World Heritage Area (J. Smith, P. Smith and K. Smith, 2019, Native Fauna of the Greater Blue Mountains World Heritage Area, P & J Smith Ecological Consultants, Blaxland). Our objective in the latter book was to document the native mammals, birds, reptiles and frogs of the World Heritage Area, with details of the distribution, abundance, habitat and conservation significance of each species. The book was intended to celebrate the outstanding diversity of native fauna in the area, to promote greater appreciation of this fauna, and to provide benchmark information that would be of value for the current and future management of the World Heritage Area.
Our book listed 68 mammals, 254 birds, 74 reptiles and 36 frogs that we considered to have been reliably recorded within the Greater Blue Mountains World Heritage Area since European settlement. Sadly, nine mammal species now appear to be locally extinct, including one which is extinct at species level (White-footed Rabbit-rat Conilurus albipes), and one which is extinct at subspecies level (an unidentied bettong, either the Tasmanian Bettong Bettongia gaimardi gaimardi or the Brush-tailed Bettong Bettongia penicillata penicillata, both of which were recorded historically in the near vicinity of the WHA). At least one frog species, the Green and Golden Bell Frog, last recorded in 1963, may also now be extinct in the World Heritage Area.
While we were writing the book, the World Heritage Area was subject to a severe and prolonged drought accompanied by record-breaking and persistent high temperatures. These extreme conditions, which are a consequence of on-going rapid climate change, culminated in the spring and summer wildfires of 2019-20. The severity and extent of the fires were unprecedented and about 80% of the Greater Blue Mountains World Heritage Area was burnt. In early 2020, the wildfires were extinguished by deluges of rain which caused serious flooding and erosion in the World Heritage Area. The full impact on the fauna of these combined events is still to be determined, but it is clear that much more now needs to be done locally to promote the recovery and resilience of the native vegetation and fauna. In the face of the increasing impact of human-induced climate change on the World Heritage Area, it is also clear that local management initiatives will not succeed in the long term unless the issue of climate change is addressed much more seriously at state, national and global levels.
We are continuing to gather information on the Blue Mountains fauna. We intend to provide occasional updates to our book in the form of four annotated checklists (one each for the mammals, birds, reptiles and frogs), which will be made available on the Blue Mountains Nature and Researchgate websites. In this first update, there are two additions to the species list: one nomadic waterbird, the Plumed Whistling-Duck, was recorded within the WHA for the first time in the summer of 2017-18; and one mammal species, the Sugar Glider, has recently been split into three separate species, two of which occur in the WHA (Krefft’s Glider and Sugar Glider in a narrower sense). Thus, the native fauna species now known from the WHA include 69 mammals, 255 birds, 74 reptiles and 36 frogs. Seventy-seven of these (28 mammals, 38 birds, 4 reptiles and 7 frogs) are listed as threatened species under either national or state legislation (as of March 2021).
This first update represents the status of the fauna prior to the events of 2019-20 and does not take account of the impact of the drought, heatwaves, wildfires and floods. It is likely that the populations and ranges of many fauna species in the area have been reduced. Many fauna species have become much more threatened and some may have become locally extinct. The changes resulting from the upheavals in 2019-20 are yet to be elucidated and documented. As more information becomes available, we hope to do further updates describing those changes. Updating the checklists is an important and on-going process. If you have additional records or other information, your feedback would be very welcome.
... nov.) based primarily on a lack of monophyly and substantial DNA sequence divergence. We believe this arrangement more accurately reflects the long isolation of the southwest WA populations from those in eastern Australia through the presence of the arid Nullarbor Barrier and is consistent with the recognition of eastern and western species of Falsistrelles (Kitchener et al., 1986), and a range of other mesic-adapted taxa including potoroos (Frankham et al., 2012), honeyeaters (Toon et al., 2010) and black cockatoos (White et al., 2011). ...
A distributional isolate in southwestern Western Australia previously assigned to Gould's Long-eared Bat Nyctophilus gouldi Tomes, 1858 is demonstrated to be a distinct and previously unnamed cryptic species, based on a lack of monophyly with eastern populations and substantial DNA sequence divergence (5.0 %) at the mitochondrial gene COI. Morphologically both species are alike and overlap in all measured characters but differ in braincase shape. The new species has one of the most restricted geographic ranges of any Australian Vespertilionidae and aspects of its ecology make it vulnerable to human impacts.
... Despite its high biodiversity, the phylogeography of mesic southeastern Australia remains poorly understood (Byrne et al., 2011). In eastern New South Wales, the role of the peaks of the Great Dividing Range in providing mesic refugia during past aridity cycles and the impacts of major river valleys as barriers to gene flow in shaping the phylogeography of the region is only just being recognized and explored (Chapple et al., 2011;Frankham et al., 2012;Hazlitt et al., 2014). However, ongoing research is hampered by a lack of suitable samples from key taxa and areas. ...
... The composition of these tribes has been relatively uncontroversial, with the exception of uncertainty surrounding the affinities of the recently extinct desert rat-kangaroo (Caloprymnus campestris), which morphologically appears to belong to Bettongini (Flannery 1989) but may have affinity with Potoroini based on limited molecular data . At the species level, recent molecular studies suggest that the taxonomy of Bettongia and Potorous is in need of revision, with the presence of cryptic, currently undescribed diversity (Frankham et al. 2012;Haouchar et al. 2016). In addition, the now extinct Bettongia anhydra was recently recognized as a separate species (McDowell et al. 2015); similar to peramelemorphians (see above), it seems likely that further recently extinct potoroid species will be identified in future. ...
Marsupials and their fossil relatives, which collectively comprise Metatheria, have been of scientific interest for centuries, with many aspects of their evolution and systematics subject to intense research and debate. Here, we review progress over the last 25 years, which has included the description of many new species (modern and fossil), and major improvements in understanding of their phylogenetic relationships, as well as the overall evolutionary history and biogeography of Marsupialia (crown-clade) and Metatheria (total-clade). Significant advances have included the deployment of increasingly sophisticated molecular, morphological, and total evidence analyses, which have resolved most previously disputed relationships among and within the modern marsupial orders. A broad systematic consensus is now emerging, although several major areas of contention remain, particularly among fossil metatherians. New modern species continue to be described at an impressive rate, with almost 50 named in the last 25 years, and many more await discovery. There has also been an explosion in the discovery and description of fossil marsupials and non-marsupial metatherians (~270 species), principally from Australasia and the Americas but also from Antarctica, Europe, and Asia. Most are represented by dental specimens only, but some consist of complete and well-preserved material, which has led to major improvements in our understanding of the evolution of cranial and postcranial morphology. Improvements in the fossil record and advances in methods for inferring divergence times have helped clarify when and where key events occurred in metatherian evolution, and the patterns of subclade diversification. We also have improved understanding of biogeographical relationships among metatherians on different landmasses. Despite enormous progress, numerous key uncertainties remain due to major gaps in the fossil record (e.g., Antarctica, Late Cretaceous, and early Paleogene of Australia) and a comparative lack of studies that directly combine molecular and fossil data. Future advances will largely depend on improvements in the fossil record and studies that better integrate neontological and paleontological evidence. Los marsupiales y sus parientes fósiles, que en conjunto forman el grupo Metatheria, han sido de interés científico durante siglos, con muchos aspectos de su evolución y sistemática sujetos a intensas investigaciones y debates. Aquí se resumen los avances alcanzados durante los últimos 25 años, los cuales incluyen la descripción de muchas especies nuevas (tanto fósiles como actuales), una mayor comprensión de relaciones filogenéticas, y también la historia general evolutiva y biogeográfica de Marsupialia (clado corona) y Metatheria (clado completo). Los mayores avances han incluido el uso de análisis moleculares, morfológicos y de evidencia total que son cada vez más sofisticados. Dichos avances ya han resuelto muchas de las relaciones anteriormente disputadas fuera y dentro de los ordenes de marsupiales actuales. Actualmente está surgiendo un amplio consenso general, a pesar de que aún quedan varias áreas importantes de discusión. Se continúa describiendo especies nuevas actuales a una velocidad impresionante, con casi 50 nombradas en los últimos 25 años, y muchas más esperan a ser descubiertas. También ha habido una explosión en el descubrimiento y descripción de especies fósiles de marsupiales y metaterios no-marsupiales (~270 especies), principalmente de Australasia y las Américas, pero
... t. tridactylus) is separated from the southern mainland subspecies (P. t. trisulcatus) by the Sydney Basin (Frankham et al. 2012). ...
The Northern Long-nosed Potoroo Potorous tridactylus tridactylus is progressively disappearing from habitat remnants on the far north coast of New South Wales and is in danger of becoming extinct on the northern coastal plain. In this review we show how the speed and scale of coastal development continues to adversely affect the four remaining areas of habitat where the species has been recorded since 2000. As an ecological specialist, the potoroo may be inherently susceptible to decline in a rapidly changing environment and persistence of the species in the coastal zone is now dependent on the success of conservation management practices in four small 'anthropogenic' refugia. © 2018 Royal Zoological Society of New South Wales. All rights reserved.
... There are also species which show diversity within Tasmania and high haplotype diversity compared with mainland Australia, these species act as a baseline for what we would expect in the sugar glider if it was indeed a native to Tasmania (Chapman, 2001;Dubey & Shine, 2010;Frankham, Handasyde, & Eldridge, 2012;Gongora et al., 2012;Symula, Keogh, & Cannatella, 2008;Zenger, Eldridge, & Cooper, 2003 Figure S13). Further, there are species which show the same genetic signal as the sugar glider with zero diversity in Tasmania where the mainland individuals have a high diversity (Burridge et al., 2013). ...
Aim
Range expansions facilitated by humans or in response to local biotic or abiotic stressors provide the opportunity for species to occupy novel environments. Classifying the status of newly expanded populations can be difficult, particularly when the timing and nature of the range expansion are unclear. Should native species in new habitats be considered invasive pests or actively conserved? Here, we present an analytical framework applied to an Australian marsupial, the sugar glider ( Petaurus breviceps ), a species that preys upon on an endangered parrot in Tasmania, and whose provenance was uncertain.
Location
Tasmania, Australia.
Methods
We conducted an extensive search of historical records for sugar glider occurrences in Tasmania. Source material included museum collection data, early European expedition logs, community observation records, and peer‐reviewed and grey literature. To determine the provenance of the Tasmanian population, we sequenced two mitochondrial genes and one nuclear gene in Tasmanian animals ( n = 27) and in individuals across the species' native range. We then estimated divergence times between Tasmania and southern Australian populations using phylogenetic and Bayesian analyses.
Results
We found no historical evidence of sugar gliders occurring in Tasmania prior to 1835. All Tasmanian individuals ( n = 27) were genetically identical at the three genes surveyed here with those individuals being 0.125% divergent from individuals from a population in Victoria. Bayesian analysis of divergence between Tasmanian individuals and southern Australian individuals suggested a recent introduction of sugar gliders into Tasmania from southern Australia.
Main conclusions
Molecular and historical data demonstrate that Tasmanian sugar gliders are a recent, post‐European, anthropogenic introduction from mainland Victoria. This result has implications for the management of the species in relation to their impact on an endangered parrot. The analytical framework outlined here can assist environmental managers with the complex task of assessing the status of recently expanded or introduced native species.
... Another apparent zone of transition between biotas in this region occurs around the Clarence River Valley, at the very southern end of the MMO, known as the Clarence River Corridor (CRC, Fig. 6; Mellick, Lowe & Rossetto, 2011;Mellick et al., 2012). The CRC appears to have been important in the diversification of several closed forest geckos (Couper et al., 2008;Colgan, O'Meally & Sadlier, 2009), fish (Rourke & Gilligan, 2010), plants (Mellick et al., 2011(Mellick et al., , 2012Heslewood et al., 2014;Van Der Merwe et al., 2014), and mammals (Frankham, Handasyde & Eldridge, 2012;Rowe et al., 2012). Likewise, some taxa appear to be restricted by the intersection of open woodland around the Glasshouse Mountains region north of Brisbane (Crisp, Linder & Weston, 1995). ...
The influence of climatic changes occurring since the late Miocene on Australia’s eastern mesic ecosystems has received significant attention over the past 20 years. In particular, the impact of the dramatic shift from
widespread rainforest habitat to a much drier landscape in which closed forest refugia were dissected by open
woodland/savannah ecosystems has long been a focal point in Australian ecology and biogeography. Several
specific regions along the eastern coast have been identified previously as potentially representing major
biogeographical disjunctions for closed forest taxa. Initially, evidence stemmed from recognition of common zones where avian species/subspecies distributions and/or floral communities were consistently separated, but the body of work has since grown significantly with the rise of molecular phylogeographic tools and there is now a significant literature base that discusses the drivers, processes and effects of these hypothesised major biogeographical junctions (termed barriers). Here, we review the literature concerning eight major barriers argued to have influenced closed forest taxa; namely, the Laura Basin, Black Mountain Corridor, Burdekin Gap, Saint Lawrence Gap, Brisbane Valley Barrier, Hunter Valley Barrier, Southern Transition Zone and East Gippsland Barrier. We synthesise reported phylogeographical patterns and the inferred timing of influence with current climatic, vegetation and geological characteristics for each barrier to provide insights into regional evolution and seek to elicit common trends. All eight putative biogeographical barriers are characterised currently by lowland zones of drier, warmer, more open woodland and savannah habitat, with adjacent closed forest habitats isolated to upland cool, wet refugia. Molecular divergence estimates suggest two pulses of divergence, one in the early Miocene (~20–15 Mya) and a later one from the Pliocene–Pleistocene (~6–0.04 Mya). We conclude with a prospectus for future research on the eastern Australian closed forests and highlight critical issues for ongoing studies of biogeographical barriers worldwide.
... Prior to European settlement, potoroos were widely distributed across the continent. However, the combined pressure of habitat loss and introduced predators and competitors (Frankham et al., 2012) resulted in dramatic range reductions for most potoroos. P. platyops is extinct, P. tridactylus is listed as vulnerable, P. longipes is endangered and P. gilbertii is critically endangered. ...
... Whereas changes in climate across the LGM have been implicated for extirpation and recolonization of mid-latitude populations in the Northern Hemisphere [72], they appear to have been less influential on species distributions at similar latitudes in the Southern Hemisphere [73,74]. Other animals presently distributed in Tasmania and mainland Australia, including prey species of A. audax, exhibit genetic divergences compatible with occupation of Tasmania during glacial periods [24,[75][76][77]. Therefore, the hypothesis that we have reconstructed the first arrival in Tasmania of A. audax can only be rejected by fossil or subfossil evidence for an earlier occupation, of which we are unaware. ...
Populations on continental islands are often distinguishable from mainland conspecifics with respect to body size, appearance, behaviour or life history, and this is often congruent with genetic patterns. It is commonly assumed that such differences developed following the complete isolation of populations by sea-level rise following the Last Glacial Maximum (LGM). However, population divergence may predate the LGM, or marine dispersal and colonization of islands may have occurred more recently; in both cases, populations may have also diverged despite ongoing gene flow. Here, we test these alternative hypotheses for the divergence between wedge-tailed eagles from mainland Australia (Aquila audax audax) and the threatened Tasmanian subspecies (Aquila audax fleayi), based on variation at 20 microsatellite loci and mtDNA. Coalescent analyses indicate that population divergence appreciably postdates the severance of terrestrial habitat continuity and occurred without any subsequent gene flow. We infer a recent colonization of Tasmania by marine dispersal and cannot discount founder effects as the cause of differences in body size and life history. We call into question the general assumption of post-LGM marine transgression as the initiator of divergence of terrestrial lineages on continental islands and adjacent mainland, and highlight the range of alternative scenarios that should be considered.
Climatic and evolutionary processes are inextricably linked to conservation. Avoiding extinction in rapidly changing environments often depends upon a species’ capacity to adapt in the face of extreme selective pressures. Here, we employed exon capture and high‐throughput next‐generation sequencing to investigate the mechanisms underlying population structure and adaptive genetic variation in the koala (Phascolarctos cinereus), an iconic Australian marsupial that represents a unique conservation challenge because it is not uniformly threatened across its range. An examination of 250 specimens representing 91 wild source locations revealed that five major genetic clusters currently exist on a continental scale. The initial divergence of these clusters appears to have been concordant with the Mid‐Brunhes Transition (∼ 430–300 kya), a major climatic reorganization that increased the amplitude of Pleistocene glacial‐interglacial cycles. While signatures of polygenic selection and environmental adaptation were detected, strong evidence for repeated, climate‐associated range contractions and demographic bottleneck events suggests that geographically isolated refugia may have played a more significant role in the survival of the koala through the Pleistocene glaciation than in situ adaptation. Consequently, the conservation of genome‐wide genetic variation must be aligned with the protection of core koala habitat to increase the resilience of threatened populations to accelerating anthropogenic threats. Finally, we propose that the five major genetic clusters identified in this study should be accounted for in future koala conservation efforts (e.g. guiding translocations), as existing management divisions in the states of Queensland and New South Wales do not reflect historic or contemporary population structure.
Taxonomic distinction of species forms the foundation of biodiversity assessments and conservation priorities. However, traditional morphological and/or genetics-based taxonomic assessments frequently miss the opportunity of elaborating on the ecological and functional context of species diversification. Here, we used 3D geometric morphometrics of the cranium to improve taxonomic differentiation and add ecomorphological characterization of a young cryptic divergence within the carnivorous marsupial genus Antechinus. Specifically, we used 168 museum specimens to characterize the recently proposed clades A. stuartii ‘south’, A. stuartii ‘north’ and A. subtropicus. Beyond slight differences attributable to overall size (and, therefore, not necessarily diagnostic), we also found clear allometry-independent shape variation. This allowed us to define new, easily measured diagnostic traits in the palate, which differentiate the three clades. Contrary to previous suggestions, we found no support for a latitudinal gradient as causing the differentiation between the clades. However, skull shape co-varied with temperature and precipitation seasonality, suggesting that the clades may be adapted to environmental variables that are likely to be impacted by climate change. Our study demonstrates the use of 3D geometric morphometrics to improve taxonomic diagnosis of cryptic mammalian species, while providing perspectives on the adaptive origins and potential future threats of mammalian diversity.
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.
Marsupials or metatherians are a group of mammals that are distinct in giving birth to young at early stages of development and in having a prolonged investment in lactation. The group consists of nearly 350 extant species, including kangaroos, koala, possums, and their relatives. Marsupials are an old lineage thought to have diverged from early therian mammals some 160 million years ago in the Jurassic, and have a remarkable evolutionary and biogeographical history, with extant species restricted to the Americas, mostly South America, and to Australasia. Although the group has been the subject of decades of phylogenetic research, the marsupial tree of life remains controversial, with most studies focusing on only a fraction of the species diversity within the infraclass. Here we present the first Methaterian species-level phylogeny to include 80% of the extant marsupial species and five nuclear and five mitochondrial markers obtained from Genbank and a recently published retroposon matrix. Our primary goal is to provide a summary phylogeny that will serve as a tool for comparative research. We evaluate the extent to which the phylogeny recovers current phylogenetic knowledge based on the recovery of “benchmark clades” from prior studies—unambiguously supported key clades and undisputed traditional taxonomic groups. The Bayesian phylogenetic analyses recovered nearly all benchmark clades but failed to find support for the suborder Phalagiformes. The most significant difference with previous published topologies is the support for Australidelphia as a group containing Microbiotheriidae, nested within American marsupials. However, a likelihood ratio test shows that alternative topologies with monophyletic Australidelphia and Ameridelphia are not significantly different than the preferred tree. Although further data are needed to solidify understanding of Methateria phylogeny, the new phylogenetic hypothesis provided here offers a well resolved and detailed tool for comparative analyses, covering the majority of the known species richness of the group.
The Long-nosed Potoroo Potorous tridactylus tridactylus has declined substantially on the far north coast of New South Wales. In this study, the known and potential habitat of the Long-nosed Potoroo on the coastal sandplain in the region is mapped in detail for the first time. A total of 3,613 ha of potential habitat is distributed in 10 areas from 24 ha to 1,423 ha in size. Heathy Scribbly Gum Eucalyptus signata woodland was considered to be particularly significant habitat in the region. While there is evidence that eight of the areas mapped once supported potoroos, their presence has only been confirmed in four of them since 2000.Targeted survey at known sites where the Long-nosed Potoroo has not been recently confirmed is urgently required, as well as a thorough reassessment of its conservation status in the region. Ecological research into threats and food preferences, and implementation of targeted conservation management actions is also needed.
With a standard set of primers directed toward conserved regions, we have used the polymerase chain reaction to amplify homologous segments of mtDNA from more than 100 animal species, including mammals, birds, amphibians, fishes, and some invertebrates. Amplification and direct sequencing were possible using unpurified mtDNA from nanogram samples of fresh specimens and microgram amounts of tissues preserved for months in alcohol or decades in the dry state. The bird and fish sequences evolve with the same strong bias toward transitions that holds for mammals. However, because the light strand of birds is deficient in thymine, thymine to cytosine transitions are less common than in other taxa. Amino acid replacement in a segment of the cytochrome b gene is faster in mammals and birds than in fishes and the pattern of replacements fits the structural hypothesis for cytochrome b. The unexpectedly wide taxonomic utility of these primers offers opportunities for phylogenetic and population research.
The elusive nature of the long-nosed potoroo (Potorous tridactylus) has hindered the collection of long-term data for this threatened species. Between June 2005 and May 2009, data on the ecology of a wild population of long-nosed potoroos located on French Island, Victoria, were collected during a series of research projects. Over this period, 33 individual potoroos were trapped a total of 251 times. Up to nine individuals were known to be alive at once on the 15-ha study site of mature remnant native forest. Adult potoroos showed high site fidelity and significant sexual size dimorphism, with males heavier and having longer head and pes lengths than females. Congruent with other studies, we found no evidence of seasonality in breeding. Births occurred in every month of the year and the testis volume of males did not vary throughout the year. In contrast to previous studies, however, we did not observe peaks in breeding activity. Our research and review of existing literature suggests that the ecology of the long-nosed potoroo is strongly influenced by local environmental conditions and emphasises the need to consider long-term and site-specific data when developing management strategies to conserve this ecologically important species.
The population biology of the long-nosed potoroo (Potorous tridactylus) was investigated at Barren Grounds Nature Reserve and Budderoo National Park in the Southern Highlands of New South Wales (NSW). Both study areas are important conservation reserves for this threatened species, with a large gap north (~300 km) to the next known viable population on the mid-north coast of NSW at Mount Royal. Potoroos were live-trapped using bandicoot-sized cage traps, each set ~100 m apart along walking tracks and fire trails. Trapping was conducted each autumn and spring over five years to enumerate the local population of potoroos and to describe their morphometrics. The local long-nosed potoroos were larger in size than those recorded to the south on mainland Australia, but smaller than those in north-eastern NSW, supporting the concept of a latitudinal cline in body size. Sexual dimorphism was observed, with adult males having larger body weights, head lengths and pes lengths. Between one-third and two-thirds of all males and females were captured in only a single trapping session, indicative of low levels of survivorship and/or high levels of dispersal or transience. Males regularly overlapped at trap sites with females, more so than with other males, while females rarely overlapped at trap sites. Barren Grounds Nature Reserve supported a larger number of potoroos and a greater degree of home range overlap between individuals.
The brush-tailed phascogale (Phascogale tapoatafa) is
considered locally rare and vulnerable, despite being found in all mainland
states of Australia. It is rarely detected in faunal surveys and the two most
immediate conservation requirements are a determination of its current range
and clarification of its taxonomic status. Measures of genetic differentiation
amongst Phascogale tapoatafa populations in eastern,
western and northern Australia were estimated using a partial (348 bp)
sequence of mitochondrial DNA (cytochrome b gene).
Observed sequence divergence within P. tapoatafa was
substantial, with an average of 13% separating the allopatric
populations in south-eastern, south-western and northern Australia. In
comparison, an average of 16% sequence divergence separated the two
currently recognised Phascogale species
(P. tapoatafa andP. calura). Thus,
Phascogale comprises four highly divergent lineages,
suggesting that the genus is more diverse than previously thought. These data
indicate that further taxonomic research is warranted.
Stony deserts are durable indicators of aridity but until now have not been directly dated. Using 21Ne and 10Be produced in surface rocks by cosmic rays, we show that Australian stony deserts formed 2 4 Ma, at the time when global cooling initiated the Quaternary ice ages and intensified aridity-induced major landscape changes in central Australia. This is the first direct determination of stony desert ages, using a new method for determining cosmogenic 21Ne in the presence of various neon components from other sources.
Kangaroos and kin (Macropodiformes) are the most conspicuous elements of the Australasian marsupial fauna. The approximately 70 living species can be divided into three families: (1) Hypsiprymnodontidae (the musky rat kangaroo); (2) Potoroidae (potoroos and bettongs); and (3) Macropodidae (larger kangaroos, wallabies, banded hare wallaby and pademelons). Here we examine macropodiform relationships using protein-coding portions of the ApoB, BRCA1, IRBP, Rag1 and vWF genes via maximum parsimony, maximum likelihood and Bayesian methods. We estimate times of divergence using two different relaxed molecular clock methods to present a timescale for macropodiform evolution and reconstruct ancestral states for grades of dental organisation. We find robust support for a basal split between Hypsiprymnodontidae and the other macropodiforms, potoroid monophyly and macropodid monophyly, with Lagostrophus as the sister-taxon to all other macropodids. Our divergence estimates suggest that kangaroos diverged from Phalangeroidea in the early Eocene, that crown-group Macropodiformes originated in the late Eocene or early Oligocene and that the potoroid-macropodid split occurred in the late Oligocene or early Miocene followed by rapid cladogenesis within these families 5 to 15million years ago. These divergence estimates coincide with major geological and ecological changes in Australia. Ancestral state reconstructions for grades of dental organisation suggest that the grazer grade evolved independently on two different occasions within Macropodidae.
Predation by European red foxes is believed to be the major cause of the extinction and decline of a large number of native medium-sized terrestrial mammals in Australia. We examined the impact of poisoning of foxes on the relative abundance of a group of medium-sized mammals in an experiment conducted in three large forest blocks in south-eastern Australia. The blocks consisted of paired sites, as follows: one site where poison baiting was used to control foxes (treatment site) and one where foxes were not controlled (non-treatment site). At all six sites, the population responses of a range of mammals were measured, and compared between treatment and non-treatment sites. The relative fox abundance, as indexed by bait-take, declined during the course of the study at treatment sites and to a lesser extent at non-treatment sites. The decline in bait-take at non-treatment sites was most likely due to treatment sites acting as ecological traps, so that reduced intra-specific competition attracted foxes from non-treatment to treatment sites, where they were subsequently poisoned. There was a significant treatment effect for the abundances of total mammals, long-nosed potoroos, southern brown bandicoots and common brushtail possums, with higher abundances at treatment sites than at non-treatment sites. Common ringtail possums increased in abundance during the course of the study, with no significant difference between treatment and non-treatment sites. There was no significant effect of time or treatment on the abundance of long-nosed bandicoots. The increase in the abundance of native mammals at treatment sites was most likely due to a lower predation pressure by foxes brought about by fox control, and the smaller increase in abundance in non-treatment blocks was likely due to the ecological-trap effect because of fox baiting at treatment sites. The present study demonstrated that broad-scale fox control can lead to increases in the abundance of native mammals in forested habitats, without recourse to aerial baiting or fences. The study also demonstrated that the influence of fox control on the fox abundance can extend well beyond the perimeter of the area baited.
Chromosome morphology was examined for male and female Gilbert’s potoroo, Potorous gilbertii, to infer taxonomic and evolutionary relationships among the extant taxa within the genus Potorous. P. gilbertii has the same number of chromosomes as P. tridactylus, 2n = 12,13. Giemsa-banding patterns were very similar in P. gilbertii and P. tridactylus; however, differences were noted between the sex chromosomes. Given that the relationships among extant Potorous are unresolved, we mapped karyotypes onto two alternative phylogenies to suggest methods of karyotype evolution within this group. Karyotypes and molecular-based information from the now ‘presumed extinct’ P. platyops or sequencing of multiple gene regions for phylogenetic analysis within the Potoroidae would provide valuable information for resolving the issue of rooting, and hence drawing conclusions on the evolution of karyotypes within this group.
Gilbert's Potoroo was originally described by John Gould as Hypsiprymnus gilbertii, from a specimen collected by John Gilbert at 'King Geoge's Sound' in 1840. After a 125 year absence, two animals were captured within Two Peoples Bay Nature Reserve in December 1994 as part of a study to look at population genetics in a close companion, the quokka (Setonix brachyurus).
Strata of Cenozoic age occur around the southern margin of Australia as thin and discontinuous outcrops, interpolated and fleshed out by economic exploration onshore and offshore. The neritic strata fall into four sequences or allostratigraphic packages of (I) Paleocene – Early Eocene, (II) Middle Eocene – Early Oligocene, (III) Late Oligocene – Middle Miocene, and (IV) Late Miocene – Holocene age: a four-part pattern that can be seen also in the flanking pelagic and terrestrial realms including regolith deep weathering. Problems of correlation and age determination (predominantly biostratigraphic) have included biogeographical constraints (endemism in neritic molluscs and terrestrial palynomorphs, mid-latitude assemblages in calcareous plankton), and slow progress in magnetostratigraphy and chemostratigraphy. Sequence I largely repeats the Cretaceous siliciclastic–coal, marginal-marine facies (carbonate-poor, with marine and non-marine palynomorphs and agglutinated foraminifers) punctuated by marine ingressions with microfaunas and sparse macrofaunas. Sequence II contains the first carbonates in the region since the Palaeozoic and the most extensive coals of the Cenozoic anywhere. Sequence III contains the most extensive neritic carbonates and the last major coals. Sequence IV is more strongly siliciclastic than the two preceding. Each of these four second-order entities (107 years duration) comprises third-order packages each with an unconformity and marine transgression. These packages hold true right along the southern Australian margin in the sense that the hiatuses and transgression do not display significant diachroneity at the relevant time-scales (105−106 years). Recognised, delimited and correlated independently of the putatively global Exxon sequences, they are remarkably consistent with the latter, thereby providing a significant regional test. There are two widespread emphases on southern Australian geohistory and biohistory: (i) to regard the regional story as part of the global story of accreting continents, an expiring Tethys, and an episodically cooling planet; and (ii) a somewhat contrary emphasis, with the region being a special case of rapid longitudinal motion towards the equator. Both emphases are plausible with the former being the more heuristic. The stratigraphic record is strongly punctuated, the four sequences being separated by both tectonic and climatic events. Thus: the sequence I/II gap involved extensive plate-tectonic reorganisation and a new spreading regime from ca 43 Ma, coevally with early growth of Antarctic ice; in the II/III gap, deformation in marginal basins is coeval with a global low in cooling, large ice sheet and falling sea-level to ca 30 Ma; and the III/IV gap is marked by widespread cessation or contraction of stratal accumulation and withdrawal of thermophilic taxa coevally with the major expansion at ca 14 Ma of the Antarctic ice sheet, onset of intense canyon cutting, and plate-wide basin inversion.
We examine the effects of historical climate change on vertebrate differentiation in tropical rainforest by comparing phylogeographic patterns in six species of widespread rainforest-restricted herpetofauna from throughout the Wet Tropics of Australia. Qualitative and quantitative comparisons of phylogeographic structure reveal strikingly similar patterns of pre-Pleistocene vicariant population differentiation on either side of a previously identified biogeographic break (variously referred to as the Black Mountain Barrier or Corridor; BMC). While divergence across the BMC antedates the Pleistocene, the impact of Quaternary climate change is apparent in populations on either side of the BMC. Consistent with palaeoclimatological reconstructions for the region, the distribution and degree of mtDNA diversity suggests that populations were fragmented and reduced to multiple refugia during Pleistocene glacial periods, with expansion following Holocene rainforest recovery. This pattern is repeated on both sides of the BMC, but substantial differences in the amount and distribution of mtDNA diversity within species indicate the importance of species-specific ecological characteristics. The historical processes of extinction and (re)colonization revealed by the comparative phylogeographic analysis of mtDNA sequences substantiate earlier suggestions that current regional patterns of species distribution and diversity in the Wet Tropics are largely determined by local extinctions and subsequent recolonization driven by Quaternary climate changes.
Aim The mesic biome, encompassing both rain forest and open sclerophyllous forests, is central to understanding the evolution of Australia’s terrestrial biota and has long been considered the ancestral biome of the continent. Our aims are to review and refine key hypotheses derived from palaeoclimatic data and the fossil record that are critical to understanding the evolution of the Australian mesic biota. We examine predictions arising from these hypotheses using available molecular phylogenetic and phylogeographical data. In doing so, we increase understanding of the mesic biota and highlight data deficiencies and fruitful areas for future research.
The recently-developed statistical method known as the "bootstrap" can be used to place confidence intervals on phylogenies. It involves resampling points from one's own data, with replacement, to create a series of bootstrap samples of the same size as the original data. Each of these is analyzed, and the variation among the resulting estimates taken to indicate the size of the error involved in making estimates from the original data. In the case of phylogenies, it is argued that the proper method of resampling is to keep all of the original species while sampling characters with replacement, under the assumption that the characters have been independently drawn by the systematist and have evolved independently. Majority-rule consensus trees can be used to construct a phylogeny showing all of the inferred monophyletic groups that occurred in a majority of the bootstrap samples. If a group shows up 95% of the time or more, the evidence for it is taken to be statistically significant. Existing computer programs can be used to analyze different bootstrap samples by using weights on the characters, the weight of a character being how many times it was drawn in bootstrap sampling. When all characters are perfectly compatible, as envisioned by Hennig, bootstrap sampling becomes unnecessary; the bootstrap method would show significant evidence for a group if it is defined by three or more characters.
A 22 ha trap grid was established perpendicular to the dune and swale system of a small coastal reserve c.750 ha (Tyagarah Nature Reserve), to investigate habitat use and the population density of Potorous tridactylus. Trapping records indicated that certain habitat types were favoured over others. Most captures occurred in dry open shrubland and moist open shrubland. Population density was relatively low at 0.23 (known to be alive) and 0.26 (Jolly-Seber method) individuals per hectare. The distribution of P. tridactylus in the reserve was established through the random placement of 235 hair-sampling tubes. It was estimated that P. tridactylus utilised a minimum area of about 340 ha within the reserve. This area multiplied by the population density indicated a population of about 80-90 individuals within Tyagarah Nature Reserve.
Mitochondrial DNA was purified from four species of higher primates (Guinea baboon, rhesus macaque, guenon, and human) and digested with 11 restriction endonucleases. A cleavage map was constructed for the mitochondrial DNA of each species. Comparison of the maps, aligned with respect to the origin and direction of DNA replication, revealed that the species differ from one another at most of the cleavage sites. The degree of divergence in nucleotide sequence at these sites was calculated from the fraction of cleavage sites shared by each pair of species. By plotting the degree of divergence in mitochondrial DNA against time of divergence, the rate of base substitution could be calculated from the initial slope of the curve. The value obtained, 0.02 substitutions per base pair per million years, was compared with the value for single-copy nuclear DNA. The rate of evolution of the mitochondrial genome appears to exceed that of the single-copy fraction of the nuclear genome by a factor of about 10. This high rate may be due, in part, to an elevated rate of mutation in mitochondrial DNA. Because of the high rate of evolution, mitochondrial DNA is likely to be an extremely useful molecule to employ for high-resolution analysis of the evolutionary process.
At Naringal, SW Victoria, small forest fragments (<80 ha in size) comprise the remaining natural habitat for native mammals. Insular biogeographic analysis demonstrated that habitat fragmentation resulted in changes in species richness and in the composition of mammal assemblages within forest patches. Important determinants of mammal species richness were: 1) forest area and habitat richness; 2) disturbance to forest vegetation from domestic stock; and 3) time since isolation from contiguous forest. Successful persistence of long-nosed potoroo Potorous tridactylus within the fragmented environment is attributed to the survival of suitable habitat patches and to the population ecology of this species. Small body size, restricted home range, extensive range overlap, stable population structure, dispersal of both sexes, and a continuous pattern of reproduction are all attributes which facilitate survival. -from Author
The marsupial fauna of Tasmania is well known from the taxonomic standpoint, and the geographical range of the species both in Tasmania and on the mainland of Australia is also known in some detail. However, the distribution of many of the marsupials within Tasmania is very imperfectly understood and there are many pressing problems in this regard yet to be solved.
There has never been any attempt to investigate either the movements of individual animals or the microdistribution of one or more species in any one area of Tasmania. As far as I am aware the work being carried out at Canberra by Dunnet of C.S.I.R.O. is the only attempt at such studies in the southern or eastern States of Australia. The macrodistribution of several of our Tasmanian species has been worked out in more or less detail. The distribution of the brush possum, Trichosurus vulpecula , was described by Pearson (1938), Huxley (1938, 1942), and more recently by Guiler (1953) and Guiler and Ingram (1958). In all of these investigations the raw material on which the distribution curves were based was derived from fur industry statistics.
The present survey is concerned with the microdistribution and movements of individuals of two species of small marsupials in a restricted area of Tasmania on the outskirts of Hobart. Several other species are found in the same area but they are outside the scope of the present investigation.
The area chosen occupies about 80 acres on the top of a ridge to the south of Hobart in the suburb of Lower Sandy Bay. The area is native bush and it has the advantage of being located only 3 miles from the University and only 800 yards from my home. The whole area lies in one property owned by J. H. …
This study investigated the mating system of the long-nosed potoroo,
Potorous tridactylus, by examining temporal associations
between individuals, and patterns of home-range overlap. Six adult females and
five adult males were radio-tracked at intervals throughout the 24-h day from
December 1996 to March 1997 in south-western Victoria. Home ranges of
individuals overlapped with multiple members of each sex; however, intrasexual
overlap was significantly lower than intersexual overlap. When data from
consecutive radio-tracking sessions were examined, the locations of resting or
‘squat’ areas were identified. These were almost entirely
intrasexually exclusive. Male home ranges overlapped the squat areas of one or
more females; however, males did not regularly associate with every female
whose squat area they overlapped. In three of four cases, pairs of a male and
a female associated regularly and spent a greater proportion of time in close
proximity to each other than would be expected if they were moving at random.
In the past it has been assumed that males monitor the sexual status of
females while they rest in squats. If this is the case, the mating system of
long-nosed potoroos will be largely dictated by the number of female squat
areas that a male is able to regularly monitor within his home range.
The sugar glider (Petaurus breviceps) shows considerable variation in external morphology and mitochondrial DNA (mtDNA) diversity across its distribution in New Guinea and Australia. Here we investigate the phylogeography of P. breviceps in Australia using data from two mitochondrial genes (ND2 and ND4) and a nuclear gene (omega-globin). Phylogenetic analyses revealed the existence of two divergent mtDNA clades that are distributed over distinct geographical regions, one from coastal New South Wales and south-eastern Queensland and a second over the remaining distributional range of the species in Australia. The two groups generally had distinct omega-globin haplotypes that differed by one or two mutational steps. Analyses of Molecular Variation further supported the presence of at least two populations, accounting for 84.8% of the total mtDNA variation and 44% of the omega-globin variation. The general concordance of phylogeographic and population analyses suggests that population subdivision, possibly resulting from the combined influences of aridification after the Pliocene and uplift of the Great Dividing Range has impacted the evolution of P. breviceps. Our results also show that the geographical distribution of the two evolutionary lineages does not correspond with the distribution of the current morphological subspecies and we further propose that they be considered as separate Evolutionarily Significant Units for the purposes of conservation management.
Ornithologists generally believe that speciation in birds proceeds by geographical splitting of populations into isolates and subsequent divergence. This allopatric mode has been subdivided into the dumbbell or classical mechanism and the peripheral or peripatric mechanism. Speciation theory predicts that peripatric divergence should proceed more rapidly than classical allopatric differentiation. This was examined in the Australian mainland avifauna by comparing the ratios of differentiates to isolates in major and minor geographical refuges on the assumption that populations isolated in minor areas were smaller than those in major ones. An array of distinctive avian species and subspecies was found to have evolved in peripheral refuge areas of mainland Australia. However, minor regions have produced considerably fewer new forms and, moreover, at the same rate. Therefore, the prediction of speciation theory was not confirmed. Differentiates on offshore islands around Australia were also considered and found not to have contributed to species enrichment on the mainland. Birds with patchy distributions were examined and discontinuities in habitat, especially substrate and dependency on specific resources, were the main causes in the semiarid and arid parts of the Australian continent. Another active pathway of adaptation from humid to arid habitat in eastern Bassian elements was revealed: the Grey Range Divide separates some avian populations in the Lake Eyre Basin from parental populations in more coastal regions.
This study examined the coarse- and fine-scale habitat preferences of the long-nosed potoroo (Potorous tridactylus) in the Southern Highlands of New South Wales, in order to inform the management of this threatened species. Live-trapping was conducted in autumn and spring, from 2005 to 2008, at two sites. Macrohabitat preferences were examined by comparing trap success with numerous habitat attributes at each trap site. In spring 2007 and autumn 2008, microhabitat use was also examined, using the spool-and-line technique and forage digging assessments. While potoroos were trapped in a wide range of macrohabitats, they displayed some preference for greater canopy and shrub cover, and ground cover with lower floristic diversity. While most individuals also displayed preferences for various microhabitat attributes, no clear trends were evident across all individuals. Potoroos displayed some foraging preference for microhabitats with higher shrub cover densities and more open ground cover. Despite extensive fox predation risks, individual potoroos did not all preferentially utilise dense ground cover. Future management of known and potential potoroo habitat should aim to provide effective introduced predator control and enhance the diversity of vegetation attributes while avoiding practices that simplify the habitat.
Many species of herbivorous mammals declined to extinction following European settlement of inland Australia. The rufous bettong, Aepyprymnus rufescens (a macropodoid marsupial), is ecologically similar to many of these species. We used analysis of microsatellite markers to determine dispersal patterns and mating system characteristics in a cluster of local populations of A. rufescens , with the aim of gaining a better understanding of regional population dynamics in such species. Particularly, we asked whether the rufous bettong showed sourcesink dynamics, as Morton (1990) hypothesized that many mammals may have been made vulnerable to extinction through such processes. We compared populations separated by distances of up to 12 km, and detected significant genetic differentiation among local populations ( F ST =0.016). Females displayed greater genetic structuring than males, suggesting that females dispersed over shorter distances or less frequently than males. Geographic distance was weakly related to genetic distance between populations suggesting some gene flow at this scale, and paternity assignment indicated that dispersal can occur over distances of up to 6.5 km. Our study populations varied widely in density, but density did not explain the pattern of genetic differentiation observed. These findings of significant structure among populations, some influence of distance on genetic divergence and that density explains little of the divergence among populations, suggested that source-sink dynamics did not play a large role among these populations. Variance in male mating success was low (maximum assigned paternity for an individual male was 14% of offspring). While data on multiple maternity were limited, roughly half of repeat maternity was assigned to the same male, suggesting that the mating system of the rufous bettong is not purely promiscuous.
The diploid chromosome number of P. tridactylus is 2n = 12 boys, 13 girls, whereas P. longipes is 2n = 24. G-banding analysis revealed that the P. tridactylus karyotype can be artificially constructed from P. longipes chromosomes by assuming one tandem fusion, five centric fusions and one pericentric inversion. It is concluded that the ancestral Potorous karyotype was similar to P. longipes (2n = 24) and that fusion events have been important in the evolution of the P. tridactylus karyotype.
Potorous longipes, sp. nov., is described from east Gippsland, Vic. It is distinguished from P. tridactylus on the basis of cranial and pedal morphology, the presence of 24 chromosomes in both sexes (cf. P. tridactylus, 12 males, 13 females ) and electrophoretic differences in blood proteins. Descriptions of its open forest habitat are provided and its distribution relative to P. tridactylus in eastern Victoria is mapped. Brief notes on maintenance of the species in captivity are given.
Considerable morphological variation exists in potoroos (genus Potorous) from south-eastern and south-western Australia. This has resulted in as many as five species being named by various workers.
Univariate morphometric analyses on potoroos other than P. platyops revealed longitudinal clinal variation in body size across northern Tasmania and latitudinal clinal variation in muzzle proportions in populations from southern Queensland to southern Tasmania. Two multivariate techniques, the Penrose measure of distance and canonical analysis, based on 10 skull and dental measurements, supported the univariate analyses and also suggested the occurrence of clinal variation. On morphological grounds, it was not possible to distinguish separate taxa from south-eastern or south-western Australia. It is concluded that apart from P. platyops all potoroos belong to a single highly variable species, P. tridactylus.
The past and present distribution of P. tridactylus in Victoria is described and mapped. Six discrete
regional populations are identified. For each region the status of the species is assessed, revealing relative
security in all but The Grampians Region. The species' habitat preferences are assessed in terms
of vegetation, soils and climate. It is adduced from all available evidence that, overall, the species
is not endangered; provided present land management practices are not drastically altered.
The distributions of 34 species of terrestrial mammals native to Tasmania are presented as presence/
absence records on 10 x 10 km grid maps. All native species and the possibly introduced Petaurus
breviceps are included except Thylacinus cynocephalus, which is probably extinct. The distribution
maps were prepared from approximately 10 000 recent (1967-89) mammal records held on computer,
selected literature records and other sources.
Twenty-six species are widely distributed across the State. Five species have more limited distributions
confined to the east or west of the State, depending upon the occurrence of their habitats. The three
remaining species are bats that are little-recorded and their distributions are unclear. Notes on the ease
of recording species and their habitats are provided to supplement and assist the interpretation of their
distributions. Further records of all species are needed, especially from islands.
Geographic variation in potoroos (genus Potorous) from south-eastern Australia and Tasmania was investigated by electrophoretic and chromosomal techniques.
Six of the 10 potoroo blood proteins examined showed electrophoretic variation and the genetic basis of three of these was established by breeding studies. Levels of genic heterozygosity were similar in Tasmanian and mainland populations. Coefficients of genetic similarity based on 10 loci indicated that potoroos from Tasmania and the Bass Strait islands are similar to each other but different from those of mainland Australia. No chromosomal variation was observed in potoroos examined from south-eastern Australia and Tasmania. Crosses between animals from these regions produced fertile offspring.
It is concluded from this study and a related investigation on morphological variation that the genus Potorous should be separated into two species, P. platyops and P. tridactylus, with the further subdivision of the latter species into P.t. tridactylus from mainland Australia (including P. gilberti) and P.t. apicalis from Tasmania and the Bass Strait islands.
The recently-developed statistical method known as the "bootstrap" can be used to place confidence intervals on phylogenies. It involves resampling points from one's own data, with replacement, to create a series of bootstrap samples of the same size as the original data. Each of these is analyzed, and the variation among the resulting estimates taken to indicate the size of the error involved in making estimates from the original data, In the case of phylogenies, it is argued that the proper method of resampling is to keep all of the original species while sampling characters with replacement, under the assumption that the characters have been independently drawn by the systematist and have evolved independently. Majority-rule consensus trees can be used to construct a phylogeny showing all of the inferred monophyletic groups that occurred in a majority of the bootstrap samples. If a group shows up 95% of the time or more, the evidence for it is taken to be statistically significant. Existing computer programs can be used to analyze different bootstrap samples by using weights on the characters, the weight of a character being how many times it was drawn in bootstrap sampling. When all characters are perfectly compatible, as envisioned by Hennig, bootstrap sampling becomes unnecessary; the bootstrap method would show significant evidence for a group if it is defined by three or more characters.
Mitochondrial DNA (mtDNA) from 25 blue tits Parus caeruleus sampled from two populations of the Grenoble region (France) was assayed for polymorphism with 17 restriction endonucleases. Nine genotypes were found. Several mtDNA genotypes were also analysed by amplification via the polymerase chain reaction (PCR) and direct sequencing of 903 bp of the cytochrome b gene. The mtDNA polymorphism is greater in P. caeruleus than in other comparable bird species and results from the presence of two clearly differentiated mitochondrial lineages. Using the data of restriction polymorphism, the mean sequence divergence between individuals of the two lineages is 1.23%. Therefore, P. caeruleus should fall into the category II of phylogeographic pattern sensu Avise et al. (1987): discontinuous mtDNA genotypes which co–occur in the same region. P. caeruleus, like humans and other mobile species with high gene flow, seems to have lost its geographic structure in terms of mtDNA phylogeny. This unusual mitochondrial polymorphism can be explained by the recent admixture of two long–term isolated populations. This could be accounted for by two different scenarios. One assumes a simultaneous post–glacial colonization of the Grenoble region by two isolated European populations of P. caeruleus. Alternatively, hybridization between P. caeruleus and P. cyanus could have caused the observed pattern of mtDNA variation.