Evolutionary and demographic history of Eurasian long-tailed shrews (Genus Sorex; Eulipotyphla; Soricidae)

Danielle Land, MS Student

Biology
Mentor: Joseph Cook

Shrews (genus Sorex) are an evolutionarily diverse clade with 89 nominal species and a Holarctic distribution. However, demographic histories and phylogeographic relationships for many clades remain unexplored.

In this study, we tested the validity of the Sorex ‘caecutiens’ and ‘minutus’ species groups, utilizing mitochondrial cytochrome b and genomic data (SNPs, ddRAD-seq) to show that most species are composed of distinct lineages in Pacific Coastal archipelagos and continental montane endemic regions, which represent ancestral separation during fluctuating glacial cycles.

Further, demographic histories reflect climate-driven bouts of isolation and colonization across the Palearctic realm throughout the Quaternary. Comparative methods encompassing multiple closely related species provide perspectives on questions surrounding recurrent processes of expansion and isolation for mammals and associated communities (e.g., parasites).

These outcomes will ultimately help guide conservation management decisions during a time of rampant anthropogenic alteration of Earth’s natural systems in high-latitude ecosystems.