Chimnoya Nwagwu and Oliver Pergams, University of Illinois-Chicago, Chicago, IL, 60607
Classification of the Peromyscus species P. leucopus (the
white-footed mouse) and P. maniculatus bairdii (the prairie mouse) has been
problematic due to morphological similarities, though P. leucopus and P.
maniculatus bairdii clearly prefer different habitats. However, this is not
sufficient in identify the species. The two existing methods of classification
are 1) the use of external and cranial measurements and 2) electrophoresis of
salivary amylase. These methods reduce the misclassification of these species,
but they have limitations. Measurements may not take into account the full extent
of interspecies variation. Electrophoresis of salivary amylase appears
accurate, yet it is limited to fresh or frozen specimens.
In this research a new method of identifying these Peromyscus species through
mtDNA haplotypes will be developed. This method will allow the reclassification
of existing museum skins by using ancient DNA techniques. I have obtained the
known cranial and external measurements of nine museum specimens. This resulted
in three categories: A) samples that met the criteria for classification as P.
maniculatus bairdii, B) samples that met the criteria for classification as P.
leucopus, and C) samples that were potentially misclassified as P. maniculatus
bairdii. I have extracted DNA from each of these skin samples, and have
amplified the cytochrome oxidase c subunit II mitochondrial gene using PCR. I
am now sequencing this gene for each sample. If mtDNA haplotypes can be
identified corresponding to specimens of known species of museum specimens, an
important step towards resolving the classification of these species will have
been achieved.