Dale Roberts

Dale Roberts


Research Focus & Metrics

Academic Career Length

22Years (2005-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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11 May 2020 in PLOS Genetics
Verified
Journal Article
Open access
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PNPolina Yu. Novikova
Polina Yu. Novikova
IBIan G. Brennan
Ian G. Brennan
WBWilliam Booker
William Booker
MMMichael Mahony
Michael Mahony
PDPaul Doughty
Paul Doughty
SDStephen C. Donnellan
Stephen C. Donnellan
Polyploidy has played an important role in evolution across the tree of life but it is still unclear how polyploid lineages may persist after their initial formation. While both common and well-studied in plants, polyploidy is rare in animals and generally less understood. The Australian burrowing frog genus Neobatrachus is comprised of six diploid and three polyploid species and offers a powerful animal polyploid model system. We generated exome-capture sequence data from 87 individuals representing all nine species of Neobatrachus to investigate species-level relationships, the origin and inheritance mode of polyploid species, and the population genomic effects of polyploidy on genus-wide demography. We describe rapid speciation of diploid Neobatrachus species and show that the three independently originated polyploid species have tetrasomic or mixed inheritance. We document higher genetic diversity in tetraploids, resulting from widespread gene flow between the tetraploids, asymmetric inter-ploidy gene flow directed from sympatric diploids to tetraploids, and isolation of diploid species from each other. We also constructed models of ecologically suitable areas for each species to investigate the impact of climate on differing ploidy levels. These models suggest substantial change in suitable areas compared to past climate, which correspond to population genomic estimates of demographic histories. We propose that Neobatrachus diploids may be suffering the early genomic impacts of climate-induced habitat loss, while tetraploids appear to be avoiding this fate, possibly due to widespread gene flow. Finally, we demonstrate that Neobatrachus is an attractive model to study the effects of ploidy on the evolution of adaptation in animals. Polyploidy or whole genome duplication is rare in animals and usually polyploid animals reproduce asexually. The Australian burrowing frogs of the genus Neobatrachus form an interesting exception amongst vertebrates with multiple independently originated autotetraploid sexual species. We generated population genomic data from 87 animals representing all six diploid and three tetraploid species of Neobatrachus. We show that, while diploid Neobatrachus species seem to be isolated from each other, their sister tetraploid species experience substantial levels of gene flow, and have wider distributions. Furthermore, we observe asymmetric gene flow from diploids to tetraploids. Based on our genomic and climate analyses we suggest that such inter-specific hybridization mediated by whole genome duplication rescues species diversity and allows tetraploids to more easily avoid impacts of climate-induced habitat loss.

20 January 2023 in Zootaxa
Verified
Journal Article
Closed access
PDF file
MTMichael J. Tyler
Michael J. Tyler
LFLydia A. Fucsko
Lydia A. Fucsko
DRDale Roberts
Dale Roberts
With alarming frequency, significant collections in natural history museums have been destroyed or damaged through insurrections, cyclones, wars, fires, floods, or earthquakes particularly in the nineteenth century but continuing into the twentieth century with World War II bombings, fires, and earthquakes being the primary causes of loss in fifty-seven institutions across thirty countries. We review the loss or damage of museum collections globally, and their varied causes. We emphasize the benefits of dispersal of a sample of paratypes across institutions as an essential feature of taxonomic practice. We argue that museums do not own type material but are acting as perpetual custodians of type material on behalf of science and society in general, and that museums, therefore, have an obligation to minimize the risk to their collections. The significance of the loss of type material would be ameliorated if, when there are numerous paratypes or syntypes, members of a type series were distributed among several institutions. This is currently common practice but historically this was not always the case and might not be possible if only a single holotype is available. We also reaffirm the need for scientists around the globe to develop specific protocols to protect collections of biological and cultural materials from loss or damage from natural and human-created disasters now and into the future. We comment on recent moves to modify the Zoological Code of Nomenclature to allow the use of images as “type” material when describing new species with the image serving as a substitute for “physical” specimens deposited in museum collections. Although our focus is on herpetological collections, our particular interest and area of expertise, our observations apply broadly to all collections, including those of animals, plants, and anthropological or ethnographic material.

19 July 2023 in Conservation Science and Practice
Verified
Journal Article
Open access
EGEvan H. Campbell Grant
Evan H. Campbell Grant
SAStaci M. Amburgey
Staci M. Amburgey
BGBrian Gratwicke
Brian Gratwicke
Víctor José Acosta-ChavesVíctor José Acosta-Chaves
Víctor José Acosta-Chaves
ABAnat M. Belasen
Anat M. Belasen
EMErin Muths
Erin Muths
The problem of global amphibian declines has prompted extensive research over the last three decades. Initially, the focus was on identifying and characterizing the extent of the problem, but more recently efforts have shifted to evidence‐based research designed to identify best solutions and to improve conservation outcomes. Despite extensive accumulation of knowledge on amphibian declines, there remain knowledge gaps and disconnects between science and action that hamper our ability to advance conservation efforts. Using input from participants at the ninth World Congress of Herpetology, a U.S. Geological Survey Powell Center symposium, amphibian on‐line forums for discussion, the International Union for Conservation of Nature Assisted Reproductive Technologies and Gamete Biobanking group, and respondents to a survey, we developed a list of 25 priority research questions for amphibian conservation at this stage of the Anthropocene. We identified amphibian conservation research priorities while accounting for expected tradeoffs in geographic scope, costs, and the taxonomic breadth of research needs. We aimed to solicit views from individuals rather than organizations while acknowledging inequities in participation. Emerging research priorities (i.e., those under‐represented in recently published amphibian conservation literature) were identified, and included the effects of climate change, community‐level (rather than single species‐level) drivers of declines, methodological improvements for research and monitoring, genomics, and effects of land‐use change. Improved inclusion of under‐represented members of the amphibian conservation community was also identified as a priority. These research needs represent critical knowledge gaps for amphibian conservation although filling these gaps may not be necessary for many conservation actions.

20 August 2021 in Pacific Conservation Biology
Verified
Journal Article
Open access
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HGHayley M. Geyle
Hayley M. Geyle
CHConrad J. Hoskin
Conrad J. Hoskin
DBDeborah S. Bower
Deborah S. Bower
RCRenee Catullo
Renee Catullo
SCSimon Clulow
Simon Clulow
GGGraeme R. Gillespie
Graeme R. Gillespie
More than a third of the world’s amphibian species are listed as Threatened or Extinct, with a recent assessment identifying 45 Australian frogs (18.4% of the currently recognised species) as ‘Threatened’ based on IUCN criteria. We applied structured expert elicitation to 26 frogs assessed as Critically Endangered and Endangered to estimate their probability of extinction by 2040. We also investigated whether participant experience (measured as a self-assigned categorical score, i.e. ‘expert’ or ‘non-expert’) influenced the estimates. Collation and analysis of participant opinion indicated that eight species are at high risk (>50% chance) of becoming extinct by 2040, with the disease chytridiomycosis identified as the primary threat. A further five species are at moderate–high risk (30–50% chance), primarily due to climate change. Fourteen of the 26 frog species are endemic to Queensland, with many species restricted to small geographic ranges that are susceptible to stochastic events (e.g. a severe heatwave or a large bushfire). Experts were more likely to rate extinction probability higher for poorly known species (those with <10 experts), while non-experts were more likely to rate extinction probability higher for better-known species. However, scores converged following discussion, indicating that there was greater consensus in the estimates of extinction probability. Increased resourcing and management intervention are urgently needed to avert future extinctions of Australia’s frogs. Key priorities include developing and supporting captive management and establishing or extending in-situ population refuges to alleviate the impacts of disease and climate change.

1 January 2007 in Records of the Western Australian Museum
Verified
Journal Article
Open access
MAMarion Anstis
Marion Anstis
DRDale Roberts
Dale Roberts
RARonald Altig
Ronald Altig

1 December 2017 in Journal of Environmental Management
Verified
Journal Article
Closed access
RZRick Zentelis
Rick Zentelis
SBSam Banks
Sam Banks
DRDale Roberts
Dale Roberts
SDStephen Dovers
Stephen Dovers
DLDavid B Lindenmayer
David B Lindenmayer