![]() ![]() ![]() Other clades depart from this morphotype in size (very small in Tamias and very large in Marmota ), tooth shape (especially 2 clades representing Eurasian and North American subgenus Spermophilus), or in both attributes (notably Cynomys ), with frequent homoplasy. When dental morphology is mapped on published DNA-based phylogenies, Sciurotamias (Chinese rock squirrels), Ammospermophilus (antelope squirrels), and basal subgenera within Spermophilus (ground squirrels ) are shown to retain inferred primitive dental morphology-small to moderate dental size, relatively small P3, relatively narrow p4–m1 + shortened m3, and relatively low tooth-crown height. Shape variables and relative tooth crown height covary significantly across species, suggesting a common functional complex or shared genetic control. Dental shape variation primarily reflects relative size of P3 (upper cheek teeth) and relative width of p4–m1 + length of m3 (lower cheek teeth). Dental size, which correlates well with published average body mass values across species, accounts for most odontometric variation across the clade. I document odontometric variation across ground-dwelling squirrels of the Holarctic tribe Marmotini.
0 Comments
Leave a Reply. |
AuthorWrite something about yourself. No need to be fancy, just an overview. ArchivesCategories |