Sorex cinereus (masked shrew) and Sorex fumeus (smoky shrew) are syntopic species co-occurring in relict fragments of spruce–fir habitat on southern Appalachian mountaintops. We conducted phylogenetic and population genetic analyses of 20 high-elevation Sorex populations in 8 distinct boreal islands. Partial mitochondrial DNA sequences (cytochrome b and D-loop) were compared with amplified fragment length polymorphism markers obtained by restriction of whole genomic DNA. The 2 species, though similar in morphology and ecological niche, have dissimilar phylogeographic patterns. S. cinereus, despite its more limited present-day southern Appalachian range, exhibits markedly less population structure than S. fumeus. What structure is present among masked shrew populations is randomized geographically, in contrast to a distinct association between genetic partitioning and geographic location among smoky shrew populations. Disparity in post-Pleistocene population densities of these species might be implicated in the discrepant patterns of phylogeographic structuring evident in their genomes as a result of historical vicariance. Although the metapopulations of both species exhibit genetic signatures consistent with continuous historical expansion, we believe that a localized catastrophic event induced a severe genetic bottleneck in Sorex populations at Whitetop Mountain, Virginia. This study contributes to a better understanding of the repercussions of boreal habitat fragmentation on the population dynamics and genetic diversity of associated vertebrate species.
You have requested a machine translation of selected content from our databases. This functionality is provided solely for your convenience and is in no way intended to replace human translation. Neither BioOne nor the owners and publishers of the content make, and they explicitly disclaim, any express or implied representations or warranties of any kind, including, without limitation, representations and warranties as to the functionality of the translation feature or the accuracy or completeness of the translations.
Translations are not retained in our system. Your use of this feature and the translations is subject to all use restrictions contained in the Terms and Conditions of Use of the BioOne website.