6,313 research outputs found
Diversity and distribution of cave crickets in the genus Micropathus Walker, 1869, threatened short-range endemics from Tasmanian wet forest (Orthoptera: Rhaphidophoridae) — Corrigendum
No full textThe present corrigendum corrects the authorship of Micropathus in the title of Beasley-Hall & Eberhard (2025) and technical errors that occurred during the production process.
https://doi.org/10.5852/ejt.2025.1012.305
Niche divergence and the evolution of soil burrowing in Australian giant cockroaches
No full textThis poster was presented at the Australasian Evolution Society's 2017 conference in Hobart, Tasmania. This dataset has since been published:Beasley-Hall, P. G., Lee, T. R. C., Rose, H. A., Lo, N. (2018). Multiple abiotic factors correlate with parallel evolution in Australian soil burrowing cockroaches. Journal of Biogeography 45: 1515–1528.<br
Highly dynamic evolution of the chemosensory system driven by gene gain and loss across subterranean beetles
No full textAvailable online 14 February 2024Chemical cues in subterranean habitats differ highly from those on the surface due to the contrasting environmental conditions, such as absolute darkness, high humidity or food scarcity. Subterranean animals underwent changes to their sensory systems to facilitate the perception of essential stimuli for underground lifestyles. Despite representing unique systems to understand biological adaptation, the genomic basis of chemosensation across cave-dwelling species remains unexplored from a macroevolutionary perspective. Here, we explore the evolution of chemoreception in three beetle tribes that underwent at least six independent transitions to the underground, through a phylogenomics spyglass. Our findings suggest that the chemosensory gene repertoire varies dramatically between species. Overall, no parallel changes in the net rate of evolution of chemosensory gene families were detected prior, during, or after the habitat shift among subterranean lineages. Contrarily, we found evidence of lineage-specific changes within surface and subterranean lineages. However, our results reveal key duplications and losses shared between some of the lineages transitioning to the underground, including the loss of sugar receptors and gene duplications of the highly conserved ionotropic receptors IR25a and IR8a, involved in thermal and humidity sensing among other olfactory roles in insects. These duplications were detected both in independent subterranean lineages and their surface relatives, suggesting parallel evolution of these genes across lineages giving rise to cave-dwelling species. Overall, our results shed light on the genomic basis of chemoreception in subterranean beetles and contribute to our understanding of the genomic underpinnings of adaptation to the subterranean lifestyle at a macroevolutionary scale.Pau Balart-García, Tessa M. Bradford, Perry G. Beasley-Hall, Slavko Polak, Steven J. B. Cooper, Rosa Fernánde
Parallel decay of vision genes in subterranean water beetles
No full textIn the framework of neutral theory of molecular evolution, genes specific to the development and function of eyes in subterranean animals living in permanent darkness are expected to evolve by relaxed selection, ulti- mately becoming pseudogenes. However, definitive empirical evidence for the role of neutral processes in the loss of vision over evolutionary time remains controversial. In previous studies, we characterized an assemblage of independently-evolved water beetle (Dytiscidae) species from a subterranean archipelago in Western Australia, where parallel vision and eye loss have occurred. Using a combination of transcriptomics and exon capture, we present evidence of parallel coding sequence decay, resulting from the accumulation of frameshift mutations and premature stop codons, in eight phototransduction genes (arrestins, opsins, ninaC and transient receptor potential channel genes) in 32 subterranean species in contrast to surface species, where these genes have open reading frames. Our results provide strong evidence to support neutral evolutionary processes as a major contributing factor to the loss of phototransduction genes in subterranean animals, with the ultimate fate being the irreversible loss of a light detection system.Barbara L. Langille, Simon M. Tierney, Terry Bertozzi, Perry G. Beasley-Hall, Tessa M. Bradford, Erinn P. Fagan-Jeffries, Josephine Hyde, Remko Leijs, Matthew Richardson, Kathleen M. Saint, Danielle N. Stringer, Adrian Villastrigo, William F. Humphreys, Andrew D. Austin, Steven J.B. Coope
Using phylogenetics to explore interspecies genetic rescue options for a critically endangered parrot
No full textAs the global biodiversity crisis deepens, with increasing habitat fragmentation and a changing climate, innovative options for conserving species are being explored. One such conservation action is genetic rescue: introduction of new alleles to promote population fitness. However, for critically endangered species where only one viable population remains, options for introducing new alleles are limited. Interspecies hybridization offers a potential solution but requires resolution of evolutionary relationships, a sound understanding of species biology, social license, and permissive legislative frameworks. Here, we show how phylogenetics and species biology can inform genetic rescue options for the orange-bellied parrot (OBP; Neophema chrysogaster), a critically endangered Australian bird with one small remaining wild population. Our phylogenetic analysis of mitochondrial genomes and nuclear loci for all congeneric species provided strong support for OBPs being the sister species to a group comprising elegant, rock, and blue-winged parrots. Accounting for species distribution, behavior, and ecology, a captive trial of interspecific hybridization with the blue-winged parrot is recommended, including assessment of the fitness of hybrid individuals. Introduction of new alleles into the OBP genome would achieve the conservation goal of improving genetic diversity in a critically endangered species. Concurrently, legislative issues will need to be resolved.Carolyn J. Hogg, Caitlin Morrison, Jessica S. Dudley, David E. Alquezar-Planas, Perry G. Beasley-Hall, Michael J. L. Magrath, Simon Y. W. Ho, Nathan Lo, Rebecca N. Johnson, Catherine E. Gruebe
Multiple abiotic factors correlate with parallel evolution in Australian soil burrowing cockroaches
No full textAim: The ways in which abiotic factors contribute to parallel evolution—the evolution of similar, derived phenotypes in independent, closely related lineages—remain understudied. Australian cockroaches of the subfamilies Panesthiinae (“wood feeders”) and Geoscapheinae (“soil burrowers”) are two closely related groups that provide a striking example of parallel evolution of burrowing behaviour. The ancestral wood‐feeding panesthiines migrated from Asia ~20 million years ago before soil burrowing was independently acquired multiple times in the derived geoscapheines. Here, we investigate whether specific abiotic factors were associated with the parallel evolution of soil burrowing behaviour, and whether divergence events of geoscapheines from panesthiine ancestors are consistent with niche conservatism or divergence. Location: The Australian mainland, including the areas in which selected Australian Panesthiinae and Geoscapheinae cockroach species are distributed. Methods: We generated environmental niche models for members of the Australian Geoscapheinae and Panesthiinae using presence‐only data and abiotic variables related to temperature, precipitation, and soil composition from BioClim and the Australian Soil Resource Information System. We used an existing phylogenetic framework to compare environmental niche models and tested for niche conservatism versus divergence. Morphological convergence was assessed by a regression analysis and principal components analysis of leg segment and body dimensions in soil burrowers and wood feeders. Results: We found no relationship between niche similarity and time since divergence, and only limited evidence for phylogenetic signal with respect to the environmental variables examined. We found that soil burrowing behaviour is consistently correlated with thirteen abiotic factors associated with aridity, including a wider range of temperatures and lower precipitation levels. Evidence for convergence in leg morphology and body dimensions across soil burrowers was found. Main conclusions: Our results are consistent with soil burrowing behaviour evolving in response to ancient aridification events following the arrival of the Panesthiinae in Australia. Our results suggest a scenario of niche divergence between soil burrowers and each of their wood feeding sister taxa. There is evidence for morphological convergence on a “shovel‐like” protibiotarsus in the Geoscapheinae that would aid in burrowing into soil.Perry G. Beasley‐Hall, Timothy R. C. Lee,Harley A. Rose, Nathan L
What are the best practices for curating eDNA custom barcode reference libraries? A case study using Australian subterranean fauna
No full textIdentification of species for environmental assessment and monitoring is essential for understanding anthropogenic impacts on biodiversity, but for subterranean fauna this task is frequently difficult and time consuming. The implementation of environmental DNA (eDNA) metabarcoding for biodiversity discovery and assessment offers considerable promise for improving the speed, accuracy, and efficiency of species detection in ecosystems both above and below the ground. Importantly, for a better understanding of the biodiversity and ecology of organisms detected using eDNA, a custom library of known reference sequences with associated correct taxonomic metadata—i.e. a barcode reference library (BRL)—is required. Yet, minimal guidance is currently available on how an effective (i.e. shareable, multisequence, that permits metadata, and has a unified nomenclature) and accurate (i.e. verified) custom BRL can be achieved. Here, we present a detailed roadmap for curation of a BRL for subterranean fauna. To do this, we curated a custom sequence database of subterranean fauna at an environmentally sensitive location, for four gene loci useful for eDNA metabarcoding, worked toward addressing the disparate nomenclature of subterranean fauna, and summarized a best practice workflow for curation of a custom BRL that is broadly applicable.Michelle T. Guzik, Danielle N. Stringer, Jake Thornhill, Peterson J. Coates, Mieke van der Heyde, Mia J. Hillyer, Nicole E. White, Mattia Saccò, Perry G. Beasley-Hall, William F. Humphreys, Mark S. Harvey, Joel A. Huey, Nerida G. Wilson, Jason Alexander, Garth Humphreys, Rachael A. King, Steven J.B. Cooper, Adrian Pinder, Giulia Perina, Andrew M. Hosie, Lisa Kirkendale, Paul Nevill, Andrew D. Austi
Knowledge management and organizational culture
No full textThis paper explores the relationship between organisational knowledge, organisational culture, and Process Based Systems (PBS), in the U.K. National Health Service (NHS). Links between PBS and organisational culture have been observed before(Perry, 2003); the contribution made by PBS to organisational knowledge has also been suggested (Perry, 2004). However, links between organisational knowledge and organisational culture in the NHS have not been widely studied. A qualitative study of these links across clinical functions has been used in conjunction with a literature review to consider in particular the use of tacit knowledge and the role that might be played by PBS in mediating and sharing this "embedded" or experiential form of knowledge. While there may be some opportunity for "externalisation" (Nonaka, 1994) - the conversion of tacit to explicit knowledge, this paper argues that PBS may also contribute to "socialisation" - the direct generation of tacit knowledge by tacit knowledge.Process Based Systems, knowledge management, organisational culture
Shrinking in the dark: Parallel endosymbiont genome erosions are associated with repeated host transitions to an underground life
No full textFirst published: 10 March 2024Microbial symbioses have had profound impacts on the evolution of animals. Conversely, changes in host biology may impact the evolutionary trajectory of symbionts themselves. Blattabacterium cuenoti is present in almost all cockroach species and enables hosts to subsist on a nutrient-poor diet. To investigate if host biology has impacted Blattabacterium at the genomic level, we sequenced and analyzed 25 genomes from Australian soil-burrowing cockroaches (Blaberidae: Panesthiinae), which have undergone at least seven separate subterranean, subsocial transitions from above-ground, wood-feeding ancestors. We find at least three independent instances of genome erosion have occurred in Blattabacterium strains exclusive to Australian soil-burrowing cockroaches. These shrinkages have involved the repeated inactivation of genes involved in amino acid biosynthesis and nitrogen recycling, the core role of Blattabacterium in the host-symbiont relationship. The most drastic of these erosions have occurred in hosts thought to have transitioned underground the earliest relative to other lineages, further suggestive of a link between gene loss in Blattabacterium and the burrowing behavior of hosts. As Blattabacterium is unable to fulfill its core function in certain host lineages, these findings suggest soil-burrowing cockroaches must acquire these nutrients from novel sources. Our study represents one of the first cases, to our knowledge, of parallel host adaptations leading to concomitant parallelism in their mutualistic symbionts, further underscoring the intimate relationship between these two partners.Perry G. Beasley-Hall, Yukihiro Kinjo, Harley A. Rose, James Walker, Charles S. P. Foster, Toby G. L. Kovacs, Thomas Bourguignon, Simon Y.W. Ho and Nathan L
Molecular systematics and biogeography of an Australian soil‐burrowing cockroach with polymorphic males, Geoscapheus dilatatus(Blattodea: Blaberidae)
No full textAn iconic group of arid‐adapted insects is the Australian soil‐burrowing cockroaches (Blaberidae: Geoscapheinae), large, wingless insects that evolved burrowing behaviour and associated forms in parallel from wood feeding ancestors in the subfamily Panesthiinae. A particularly problematic taxon within the Geoscapheinae is Geoscapheus dilatatus (Saussure, 1864), which might represent a species complex and whose delimitation has been complicated for decades by the species harbouring polymorphic males. Males can be divided into two main morphs: individuals possessing horn‐like protrusions on the anterior margin of the pronotum (‘tuberculate’) and those without these characters (‘non‐tuberculate’). A less common, third form consists of individuals that possess tubercles but are far larger than other tuberculate males and occur solely to the north of the species' distribution (‘atypical’ tuberculates). Here, we make use of whole mitochondrial genomes and nuclear ribosomal RNA data from individuals across the range of G. dilatatus to conduct the first phylogenetic analysis of this species to date. We recover all tuberculate males (including atypical forms) as monophyletic and the derived form of G. dilatatus, having evolved only once in this species, whereas non‐tuberculate forms are paraphyletic. Fossil‐calibrated molecular clock analysis revealed that the divergence between these two forms occurred during the late Miocene approximately 6.7 Mya, concurrent with an expansion of the continent's drier biomes. Environmental niche modelling suggests that tuberculate male forms are more climatically tolerant than their more restricted non‐tuberculate counterparts, and both forms' predicted fundamental niches are strongly limited by rainfall. Three species delimitation analyses implemented here failed to consistently delimit G. dilatatus beyond a single species. Ultimately, population genetic approaches paired with additional sampling will be necessary to determine these findings more concretely, but at present, we do not consider the results presented here sufficient to delimit G. dilatatus based on morphological differences found in the species' polymorphic males alone
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