EVOLUTION IN THE MURINAE (RODENTIA) ASSESSED BY MICROCOMPLEMENT FIXATION OF ALBUMIN

The inter-relationship of 17 genera of Murinae rodents were studied using microcomplement fixation of albumin to measure immunological distances among taxa. The genera chosen represented six major clades and four monogeneric groups identified in earlier companion studies (an African group, a South-east Asian group, a New Guinean group, an Australasian group, an Acomys group, a Micromys group and Apodemus, Millardia, Mus and Phloeomys). When these companion studies are included 136 species and 67 genera were studied. Ten major clades were consistently supported by the data but apart from linking the South-east Asian and Australasian clades, the data do not resolve their inter-relationships. The Acomys-Uranomys-Lophouromys clade may be the sister-group to the rest of the Murinae. Otomys (Otomyinae) is considered to be a murine related to the African group of genera. Of the ten major clades identified, only one (Mus) occurs significantly in more than one primary biogeographic region. It is suggested that following an early period of relatively rapid dispersal from the place of origin, little further dispersal took place and subsequent evolution occurred within relatively confined geographic areas.