Maternal Behavior and Behavioral Development in Two Subspecies of Peromyscus maniculatus

This study represents an initial step into the problem of the phylogeny of behavior in Peromyscus. The aim of the entire study is to examine the patterns of behavior in this genus and to ascertain their relation to the ecological adaptations of each species and subspecies studied. The demonstration of subspecific similarities and differences must first be undertaken, and the present paper is concerned with this aspect in the subspecies Peromyscus maniculatus bairdi and P. m, gracilis. These two subspecies are of particular interest because they represent the end products of a Rassenkreis whose ranges have recently overlapped (Hooper, 1942). Other studies of these subspecies in the field (Blair, 1940, 1942; Howard, 1949; Manville, 1949) and in the laboratory (Harris, 1952, 1954) render them useful for a comparative study. This study was supported by Grant M-123 of the...