Variation and evolutionary trends in the dentition of late pleistocene Mcrotus pennsylvanicus from three levels in bell cave, Alabama

Dental remains of the meadow vole, Microtus pennsylvanicus, were recovered from three superposed day units (zones) and four excavations (pits) in Bell Cave, Alabama. Bone collagen 14C dates of 26,500 + 480/ ‐ 500 and 11,800 + 480/‐ 500 yr BP. are associated with the bottom and top units, respectively. Length, width, number of closed triangles (five or six), and a measurement to determine the amount of closure of the sixth triangle were taken on the first lower molar (M1) from the three zones in Pits 1 and 4. Length and width of the third upper molar (M3) were also determined for the three zones in Pit 4. Analysis of Variance revealed no effect of pit origin or number of triangles on M1 length or width. A trend from large to small size in M3 is documented, but is not statistically significant The same trend is evidenced by length and width of M1. Size changes in length and width of M1 from Pit 4 are statistically significant, but those from Pit 1 are not Although there is no difference in the lengths or wi...