Biology subjects

Stojak, J.

Publications and source records attributed to Stojak, J..

3 recordsLinked to original sources

bioRxiv2022

Ancient DNA reveals interstadials as a driver of the common vole population dynamics during the last glacial period

1AimThe common vole is a temperate rodent widespread across Europe. It was also one of the most abundant small mammal species throughout the Late Pleistocene. Phylogeographic studies of its extant populations suggested the Last Glacial Maximum (LGM, 26.5-19 ka ago) as one of the main drivers of the species population dynamics. However, analyses based solely on extant genetic diversity may not recover the full complexity of past population history. The main aim of this study was to investigate the evolutionary history and identify the main drivers of the common vole population dynamics during the Late Pleistocene. LocationEurope TaxonCommon vole (Microtus arvalis) MethodsWe generated a dataset comprising 4.2 kb-long fragment of mitochondrial DNA from 148 ancient and 51 modern specimens sampled from multiple localities across Europe and covering the last 60 thousand years (ka). We used Bayesian inference to reconstruct their phylogenetic relationships and to estimate the age of specimens that were not directly dated. ResultsWe estimate the time to the most recent common ancestor of all Last Glacial and extant common vole lineages to 90 ka ago and the divergence of the main mtDNA lineages present in extant populations to between 55 and 40 ka ago, earlier than previous estimates. We find multiple lineage turnovers in Europe in the period of high climate variability at the end of Marine Isotope Stage 3 (MIS 3; 57-29 ka ago) in addition to those found previously around the Pleistocene/Holocene transition. Conversely, data from the Western Carpathians suggest continuity throughout the LGM even at high latitudes. Main conclusionsOur results suggest that the main factor affecting the common vole populations during the last glacial period was the reduction of open habitats during the interstadial periods while the climate deterioration during the LGM had little impact on species population dynamics.

evolutionary biology↗

bioRxiv2020

Next-generation phylogeography resolves post-glacial colonization patterns in a widespread carnivore, the red fox (Vulpes vulpes), in Europe.

Carnivores tend to exhibit a lack of (or less pronounced) genetic structure at continental scales in both a geographic and temporal sense and this can confound the identification of post-glacial colonization patterns in this group. In this study we used genome-wide data (using Genotyping-by-Sequencing (GBS)) to reconstruct the phylogeographic history of a widespread carnivore, the red fox (Vulpes vulpes), by investigating broad-scale patterns of genomic variation, differentiation and admixture amongst contemporary populations in Europe. Using 15,003 single nucleotide polymorphisms (SNPs) from 524 individuals allowed us to identify the importance of refugial regions for the red fox in terms of endemism (e.g. Iberia). In addition, we tested multiple post-glacial re-colonization scenarios of previously glaciated regions during the Last Glacial Maximum using an Approximate Bayesian Computation (ABC) approach that were unresolved from previous studies. This allowed us to identify the role of admixture from multiple source population post-Younger Dryas in the case of Scandinavia and ancient land-bridges in the colonization of the British Isles. A natural colonization of Ireland was deemed more likely than an ancient human-mediated introduction as has previously been proposed and potentially points to an increased mammalian fauna on the island in the early post-glacial period. Using genome-wide data has allowed us to tease apart broad-scale patterns of structure and diversity in a widespread carnivore in Europe that was not evident from using more limited marker sets and provides a foundation for next-generation phylogeographic studies in other non-model species.

evolutionary biology↗

bioRxiv2019

Phylogeographic structure of the pygmy shrew: revisiting the roles of southern and northern refugia in Europe.

Southern and northern glacial refugia are considered paradigms that explain the complex phylogeographic patterns and processes of European biota. Although the Eurasian pygmy shrew Sorex minutus Linnaeus, 1766 (Eulipotyphla, Soricidae) has been used a model species to study geographic isolation and genetic diversification in Mediterranean peninsulas in the Last Glacial Maximum (LGM), and post-glacial population expansion from cryptic northern glacial refugia in Western and Central Europe, there has been incomplete knowledge about the phylogeographic structure, genetic differentiation and demographic history within these regions. Here, we provide a revisited statistical phylogeographic study of S. minutus with greater sampling coverage in terms of numbers of individuals and geographic range, making it the most comprehensive investigation of this species to date. The results showed support for genetically distinct and diverse phylogeographic groups consistent with southern and northern glacial refugia, as expected from previous studies, but also identified geographical barriers concordant with glaciated mountain ranges during the LGM, early diversification events dated between the Upper Pleistocene and Lower Holocene for the main phylogeographic groups, and recent (post-LGM) patterns of demographic expansions. The results have implications for the conservation of intraspecific diversity and the preservation of the evolutionary potential of S. minutus.

evolutionary biology↗