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Biology subjects

Wiley, D. L. F.

Publications and source records attributed to Wiley, D. L. F..

3 recordsLinked to original sources

Mapping frog genomic diversity on a continental scale

Genetic variation is a key component of population resilience and thus an essential tool for wildlife management. For most species, however, we lack information about their current range-wide genomic diversity and how historical and contemporary factors have shaped those patterns. To address these gaps, we built new georeferenced genomic datasets for 2,481 individuals from 46 frog species to develop a genomic diversity atlas representing 43% of species native to the United States and Canada. We identified geographic "hotspots" of high genomic diversity and "coldspots" of low genomic diversity across species and analyzed potential explanations for these patterns. Our results show that several species have their lowest diversity at northern latitudes, at range edges, or within fragmented populations, suggesting areas in need of careful monitoring. More than half (56.8%) of species exhibited a latitudinal gradient in genomic diversity, but we found little evidence for an association between genomic diversity and human disturbance. Furthermore, discordant latitudinal patterns among species suggest that a combination of factors, including range center-edge dynamics and range fragmentation, interact to produce variable diversity patterns. Our study provides a general framework for mapping range-wide genomic diversity of multiple species to support genetically informed biodiversity conservation.

evolutionary biology↗

Parallel elevational replacement of hosts and parasites in a highly susceptible songbird genus

Elevational replacement distribution patterns underpin montane diversity and reflect the interaction of both biotic and abiotic pressures, but the degree to which parasites exhibit elevational zonation remains unclear. Investigating infection patterns in related host species across elevational gradients can reveal whether parasites and hosts show concordant patterns of elevational turnover, potentially due to shared historical and ecological factors. Here, we assessed patterns of elevational replacement in haemosporidian parasite assemblages that infect three congeneric songbird species: Bells vireo (Vireo bellii), gray vireo (V. vicinior), and plumbeous vireo (V. plumbeus), each of which breeds across distinct elevations and habitats in the southwestern United States. We screened a total of 248 individuals using cytochrome b PCR and microscopy. We identified 19 haemosporidian haplotypes, including eight novel lineages. We found that each of the three vireo species exhibited high haemosporidian prevalence (55.0-86.2%), with nearly all infections from the genus Haemoproteus (subgenus Parahaemoproteus). Haemosporidian assemblages varied across elevations; each sampled range of elevations harbored abundant, yet host-specific lineages with different environmental associations. Bells and plumbeous vireos, but not gray vireos, hosted several phylogenetically distinct, putative generalist lineages, likely reflecting spillover from more diverse local breeding bird communities. Repeated infections in individuals across breeding seasons, together with moderate parasitemia (x{square} {approx} 1%) suggest that these focal vireo species harbor chronic infections during their respective breeding seasons. These results demonstrate that elevational replacement patterns in avian hosts may be mirrored by their haemosporidian parasites, particularly among host-specialized lineages.

ecology↗

Caudata macrogenetics: Species range size predicts intraspecific genetic variation in global salamanders

AimGenetic diversity contains valuable information about ecological and evolutionary aspects of species. Intraspecific genetic variation is shaped by species natural history traits and by characteristics of geography and climate within their ranges. Amphibians are of ecological and conservation interest because of their global distribution, deep history, trait diversity, and roles within ecological communities. Here, we studied genetic variation within salamanders to investigate predictors of nucleotide diversity and spatial patterns of genetic differentiation. LocationGlobal. Time PeriodPresent. Major Taxa StudiedSalamanders. MethodsWe repurposed mitochondrial DNA sequences and ecological data from open-access databases for 220 salamander species. We calculated nucleotide diversity ({pi}) and tested for isolation by distance (IBD) and isolation by environment (IBE). We analyzed these three variables with random forest and phylogenetic comparative methods using 28 predictors expected to be associated with genetic variation. ResultsWe recovered 8,108 Cytb sequences with their associated geographic coordinates, of which 7,007 sequences were manually curated by us. Range size, lineage age, and sample size were important predictors of genetic variation. We found higher diversity in regions including the Neotropics and central-eastern Europe. The absence of phylogenetic signal in {pi}, IBD, and IBE suggests that genetic variation is shaped by local ecological and geographical factors rather than by shared ancestry. Main ConclusionsOur finding of range size as an important predictor aligns with theoretical expectations that species with larger ranges tend to harbor more genetic diversity. Furthermore, lineage age being an important predictor is in line with the clade-age hypothesis, in which species with longer divergence times have higher genetic diversity because they have had more time to accumulate genetic variation. Our results underscore the importance of integrating spatial data into macrogenetic studies, providing valuable information for future studies and conservation strategies targeting regions with high or low genetic diversity.

evolutionary biology↗