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Dorey, J. B.

Publications and source records attributed to Dorey, J. B..

4 recordsLinked to original sources

Nesting behaviour drives the evolution of heat tolerance and climate vulnerability in bees

Species vulnerability to climate change depends in part on their capacity to evolve in response to increasing heat1. Within terrestrial ectotherms, heat tolerance generally corresponds weakly to current climates, which has led many to conclude that this trait is evolutionarily constrained2-4. However, most studies have not accounted for the role of microclimates, potentially obscuring signals of local adaptation. We examined heat tolerance in 95 species of wild bees that varied in nesting behaviour across the latitudinal extent of Australia. Species nest (ground, wooden cavities, or plant stems) micro-climate temperatures predicted heat tolerance evolution, where stem nesters evolved the highest heat tolerances, and ground nesters evolved the lowest heat tolerances due to their ability to evade extreme heat. A moderate level of phylogenetic inertia in heat tolerance was explained by patterns of related species sharing nesting behaviours. This indicated repeated adaptive evolution of similar heat tolerances, rather than strong evolutionary constraints on heat tolerance. Finally, incorporating nesting behaviour into assessments of climate change vulnerability changed the rank order of which species were most at risk. This underscores the need to understand what drives the evolution of heat tolerance across species to better identify the taxa most at risk to climate change.

ecology↗

Environmental DNA reveals temporal and spatial variability of invertebrate communities in arid-lands ephemeral water bodies

ContextThroughout semi-arid and arid Australia surface freshwater is rare, and where it does occur, it is often ephemeral. This is the case for freshwater granite rock-holes that occur throughout much of southern Australia. Rock-holes support freshwater invertebrate communities, however, the ongoing threat of climate change means that this ecosystem is likely to experience hydrological disruptions. Rock-holes are also likely to be heavily impacted by invasive vertebrates. However, the ecology of this ecosystem is poorly understood despite its relative ecological significance and the extent of its associated threats. Aims and methodsTo provide a baseline ecological understanding of this ecosystem we documented species richness and variability at a series of rock-holes in the Gawler bioregion in South Australia using an environmental DNA approach. Key resultsMetabarcoding recorded invertebrates from 22 orders and 45 families. Community composition varied among rock-holes and throughout the year, with a peak in species richness in winter. Conclusions and implicationsThese findings demonstrate the importance of these ecosystems to a range of endemic taxa. We propose establishment of monitoring programs, development of custom barcode reference libraries for the rock-hole ecosystem and future research into the likely impacts of climate change on the communities associated with them.

ecology↗

Species richness patterns in Fijian bees are explained by constraints in physiological traits

Determining the ecological and evolutionary mechanisms that underpin patterns of species richness across elevational gradients is a key question in evolutionary ecology, and can help to understand species extinction risk under changing climates. In the tropical montane islands of Fiji, there are 28 species of endemic bee in the subgenus Lasioglossum (Homalictus), where species richness increases with elevation despite decreasing land surface (habitat) areas. We used a combination of spatially explicit phylogenetic diversity analyses and phylogenetic trait analyses to examine the factors shaping species distributions in these bees. We found that species at higher elevations had lower heat tolerance and desiccation resistance than those at lower elevations, consistent with these traits constraining species elevational ranges. We also found high species phylogenetic diversity within mountains, and high phylogenetic signal in species heat tolerance and minimum elevational ranges, consistent with these traits being evolutionarily conserved among mountain-top taxa following vicariant (allopatric) speciation. We found no evidence to suggest that interspecific competition is shaping species elevational ranges. In all, our findings indicate that phylogenetic conservatism in physiological traits related to climatic niche, such as heat tolerance, can explain why species richness is highest at mountain tops in this system, with species having tracked their climatic niches over time towards ever higher (cooler and wetter) elevations. Because high elevations in this archipelago are extremely limited ([~]2.3% of total land area), only miniscule elevational islands in the sky remain into which this diverse, but climate-restricted fauna, can retreat as climates warm.

evolutionary biology↗

BeeDC: An R package and globally synthesised and flagged bee occurrence dataset

Species occurrence data are foundational for research, conservation, and science communication, but the limited availability and accessibility of reliable data represents a major obstacle, particularly for insects, which face mounting pressures. We present BeeBDC, a new R package, and a global bee occurrence dataset to address this issue. We combined >18.3 million bee occurrence records from multiple public repositories (GBIF, SCAN, iDigBio, USGS, ALA) and smaller datasets, then standardised, flagged, deduplicated, and cleaned the data using the reproducible BeeBDC R-workflow. Specifically, we harmonised species names (following established global taxonomy), country names, and collection dates and we added record-level flags for a series of potential quality issues. These data are provided in two formats, "cleaned" and "flagged-but-uncleaned". The BeeBDC package with online documentation provides end users the ability to modify filtering parameters to address their research questions. By publishing reproducible R workflows and globally cleaned datasets, we can increase the accessibility and reliability of downstream analyses. This workflow can be implemented for other taxa to support research and conservation.

ecology↗