Leon Duobinis-Gray (MSU - top in picture at left),  Alexey Tesakov (Russian Academy of Sciences) and undergrad Chris Crockett, (MSU- bottom in picture at left) are working with me to create an inventory of scanning electron microscope (SEM) images of both modern and fossil arvicoline rodents in order to examine phylogenetic relationships within this ubiquitous group. This work, supported by a grant from the Kentucky NSF EPSCoR program, is based on the landmark discovery by Wighart von Koenigswald (University of Bonn, Germany) that the microanatomical pattern (the "schmelzmuster") changes from an initial radial structure in the earliest species to various combinations of tangential and lamellar enamel in later taxa. Lemmings have their own peculiar pattern that is simply referred to as "lemming enamel."

The schmelzmuster of Microtus ochrogaster, the prairie vole, demonstrating the typical combination of radial (upper) and lamellar (lower, criss-crossed enamel prisms) enamel on the leading edges (posterior edges) of the upper molars so characteristic of the genus. This photo was taken from the third triangle of the right first upper molar.