75 research outputs found
Vertebrates are poor umbrellas for invertebrates: cross-taxon congruence in an Australian tropical savanna
Invertebrates are commonly ignored in conservation planning due to their vast diversity, difficulties with species identification, a poor understanding of their spatial patterns, and the impracticability of carrying out comprehensive sampling. Conservation planning for fauna is therefore often based on patterns of diversity and distribution of vertebrates, under the assumption that these are representative of animal diversity more generally. Here, we evaluate how well vertebrates act as umbrellas for invertebrate diversity and distribution in a highly diverse tropical savanna landscape, and we investigate the effect of vertebrate sampling intensity (i.e., number of surveys) on congruence results. We assessed congruence between each of the four classes of terrestrial vertebrates (amphibians, reptiles, birds, and mammals) and twelve invertebrate families (representing four dominant invertebrate taxa: ants, beetles, flies, and spiders) by applying a range of modeling approaches to analyze patterns of crossâtaxon congruence in species richness and composition across sampling sites. To investigate drivers of congruence, we applied generalized and distanceâbased linear models to identify environmental associations of richness and composition for each taxon, then examined variation in environmental associations across taxa. Vertebrate and invertebrate richness was weakly (<30%) associated, and ~60% of the significant associations were negative. Correlations in species composition between vertebrate and invertebrate taxa were also weak, with a maximum of 13% congruence. In most cases, pairwise correlation scores using data from single surveys of vertebrates were only marginally lower than those from multiple surveys. Poor amongâsite congruence between vertebrates and invertebrates was reflected by marked variation among taxa in their environmental associations. Our findings show that vertebrates are poor umbrellas for invertebrates in the tropical savannas of northern Australia in terms of geographic patterns of diversity and distribution and that this is not just an artifact of low vertebrate sampling intensity. Our study is one of the most comprehensive regional analyses of the congruence of vertebrate and invertebrate diversity, and it significantly adds to the growing evidence that empirical data on invertebrate diversity and distribution are required for conservation planning that effectively protects all faunal diversity
Kidney transplant graft outcomes in 379Â 257 recipients on 3 continents
Peer Reviewedhttps://deepblue.lib.umich.edu/bitstream/2027.42/145422/1/ajt14694_am.pdfhttps://deepblue.lib.umich.edu/bitstream/2027.42/145422/2/ajt14694.pd
A national-scale dataset for threats impacting Australia's imperiled flora and fauna
Australia is in the midst of an extinction crisis, having already lost 10% of terrestrial mammal fauna since European settlement and with hundreds of other species at high risk of extinction. The decline of the nation's biota is a result of an array of threatening processes; however, a comprehensive taxon-specific understanding of threats and their relative impacts remains undocumented nationally. Using expert consultation, we compile the first complete, validated, and consistent taxon-specific threat and impact dataset for all nationally listed threatened taxa in Australia. We confined our analysis to 1,795 terrestrial and aquatic taxa listed as threatened (Vulnerable, Endangered, or Critically Endangered) under Australian Commonwealth law. We engaged taxonomic experts to generate taxon-specific threat and threat impact information to consistently apply the IUCN Threat Classification Scheme and Threat Impact Scoring System, as well as eight broad-level threats and 51 subcategory threats, for all 1,795 threatened terrestrial and aquatic threatened taxa. This compilation produced 4,877 unique taxonâthreatâimpact combinations with the most frequently listed threats being Habitat loss, fragmentation, and degradation (n = 1,210 taxa), and Invasive species and disease (n = 966 taxa). Yet when only high-impact threats or medium-impact threats are considered, Invasive species and disease become the most prevalent threats. This dataset provides critical information for conservation action planning, national legislation and policy, and prioritizing investments in threatened species management and recovery
Red hot frogs:Identifying the Australian frogs most at risk of extinction
More than a third of the worldâs amphibian species are listed as Threatened or Extinct, with a recent assessment identifying 45 Australian frogs (18.4% of the currently recognised species) as âThreatenedâ 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. âexpertâ or ânon-expertâ) 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 moderateâhigh risk (30â50% 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 Australiaâs 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
Mutations in REEP6 Cause Autosomal-Recessive Retinitis Pigmentosa
Retinitis pigmentosa (RP) is the most frequent form of inherited retinal dystrophy. RP is genetically heterogeneous and the genes identified to date encode proteins involved in a wide range of functional pathways, including photoreceptor development, phototransduction, the retinoid cycle, cilia, and outer segment development. Here we report the identification of biallelic mutations in Receptor Expression Enhancer Protein 6 (REEP6) in seven individuals with autosomal-recessive RP from five unrelated families. REEP6 is a member of the REEP/Yop1 family of proteins that influence the structure of the endoplasmic reticulum but is relatively unstudied. The six variants identified include three frameshift variants, two missense variants, and a genomic rearrangement that disrupts exon 1. Human 3D organoid optic cups were used to investigate REEP6 expression and confirmed the expression of a retina-specific isoform REEP6.1, which is specifically affected by one of the frameshift mutations. Expression of the two missense variants (c.383C>T [p.Pro128Leu] and c.404T>C [p.Leu135Pro]) and the REEP6.1 frameshift mutant in cultured cells suggest that these changes destabilize the protein. Furthermore, CRISPR-Cas9-mediated gene editing was used to produce Reep6 knock-in mice with the p.Leu135Pro RP-associated variant identified in one RP-affected individual. The homozygous knock-in mice mimic the clinical phenotypes of RP, including progressive photoreceptor degeneration and dysfunction of the rod photoreceptors. Therefore, our study implicates REEP6 in retinal homeostasis and highlights a pathway previously uncharacterized in retinal dystrophy
The bleating tree frog \u27Litoria dentata\u27 Keferstein (Anura: Hylidae): An addition to the frog fauna of Victoria
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Status of mammals on Groote Eylandt: safe haven or slow burn?
Native mammals across northern Australia have suffered severe decline, with feral cats (Felis catus), introduced herbivores and changed fire regimes being implicated as drivers. However, uncertainty surrounding the relative contribution of each of these threats, and the interactions between them, is limiting the development of effective management strategies. The absence of introduced herbivores and cane toads (Rhinella marina) on Groote Eylandt, Northern Territory, provides an opportunity to evaluate some hypothesised threats in isolation of others. We used camera traps to investigate the correlates of native mammal distribution and abundance at 112 lowland savanna sites across Groote Eylandt. Two large grids of camera traps were also deployed to obtain estimates of feral cat density. We hypothesised that native mammal populations would be negatively associated with feral cat occupancy as well as frequent, large fires. Native mammal siteâoccupancy on Groote Eylandt was generally higher compared to mainland Northern Territory. Feral cats were infrequently detected, precluding both an estimate of feral cat density and an evaluation of the relationship between feral cats and native mammals. We found no evidence that native mammal siteâoccupancy or relative abundance is negatively associated with frequent, large fires. The relatively healthy state of native mammal populations on Groote Eylandt is likely due to the low density of feral cats, the benign fire regime and the absence of large introduced herbivores and cane toads. However, due to a lack of historical data, the current state of mammals should not be taken as evidence that these populations are safe from decline. This study highlights that the apparent resilience of mammal populations is a result of complex interactions between factors that vary substantially across the landscape. Caution is therefore required when making broad inferences about the drivers of mammal decline from studies that are spatially and temporally limited
Lizard responses to forest fire and timber harvesting: complementary insights from species and community approaches
Understanding the relationship between community composition and ecosystem function is essential for managing forests with complex disturbance regimes. Studies of animal responses to fire and timber harvesting in forest ecosystems typically focus on a single level of community diversity. Measures of species abundance and diversity at the community level, along with measures of functional diversity that incorporate information on species traits, provide opportunities for complementary insights into biodiversity responses to disturbances. We quantified community and functional responses of a temperate forest lizard community to fire and rotational logging using metrics including species-specific abundance, community abundance, species richness and evenness, as well as trait-based measures of functional diversity. We used non-linear regression models to examine the relationships between reptile data and time since fire and timber harvesting, using sites arrayed along a 30-years post-disturbance chronosequence. We modelled responses separately in two major vegetation types: coastal Banksia woodland and lowland eucalypt forests. Species and community measures offered different insights into the role of fire and logging. Species responses to disturbance differed between disturbance type and vegetation type. Four species exhibited significant population responses to either fire or timber harvesting, while the rest were unaffected by either disturbance. At the community level, species richness and community abundance increased significantly with time since fire in woodland vegetation. In forest vegetation, community abundance decreased with time since fire. Surprisingly, community evenness and functional diversity did not show marked responses to fire or timber harvesting. This is likely a result of trait homogeneity and the asynchrony in species responses to disturbance. We advocate using multiple measures of community composition - incorporating species-specific information, community metrics and functional traits - to ensure a more holistic understanding of disturbance ecology in forest landscapes
Habitat use by stream-breeding frogs in south-east Sulawesi, with some preliminary observations on community organization
A new velvet gecko (Oedura: Diplodactylidae) from Groote Eylandt, Northern Territory
Over the last decade, the combination of biological surveys, genetic diversity assessments and systematic research has revealed a growing number of previously unrecognised vertebrate species endemic to the Australian Monsoonal Tropics. Here we describe a new species of saxicoline velvet gecko in the Oedura marmorata complex from Groote Eylandt, a large island off the eastern edge of the Top End region of the Northern Territory.Oedura nesos sp. nov. differs from all congeners in combination of moderate size, and aspects of tail morphology and colouration. It has not been reported from the nearby mainland regions (eastern Arnhem Land) suggesting it may be an insular endemic, although further survey work is required to confirm this. While Groote Eylandt is recognised as a contemporary ecological refuge for declining mammal species of northern Australia, newly detected endemic species suggest it may also be of significance as an evolutionary refuge for many taxa, especially those associated with sandstone escarpmentsRevisionary and survey work
on the Oedura marmorata complex has been funded by a McKenzie Postdoctoral Fellowship from the University
of Melbourne to PMO, an Australian Research Council Discovery early career researcher fellowship to PMO, an
Australian Research Council linkage grant to PMO, P. Doughty, and M. Lee, an Australian Biological Resources
Survey Grant to M. Adams, PMO, P. Doughty, and M. Lee, and an ARC Laureate Fellowship to C. Moritz
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