Evolutionary history and phylogeographic relationships of shrews from Sorex araneus group
Fig 8
A hypothetical scenario for geographic dispersion of Sorex araneus group.
A. (3.5–2.7 Mya) An ancestral population is widespread in the whole Eurasia and migrates into Alaska across a land bridge, which existed in the place of the current Beringia Strait. B. (2.7–2.4 Mya) The S. samniticus lineage emerges within the western European population. This species survived until today in the Apennine Peninsula. The Alaskan population expands into North America. C. (2.4–2.2 Mya) The immigrated population occupies the central and eastern regions of North America. Ancestors of present Sorex lineages emerge within the Eurasian and North American populations. D. (2.2–1.4 Mya) The Eurasian population splits into the west and east lineages. The west population spreads into Europe and gives the origin to S. granarius, restricted currently to Iberian Peninsula. The east population differentiates into S. tundrensis and S. asper, whereas the North American population into S. arcticus and S. maritimensis. S. tundrensis migrates into Alaska across Beringia Strait.