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

The inter-relationship of 17 genera of Murinae rodents were studied us ing microcomplement fixation of albumin to measure immunological dista nces among taxa. The genera chosen represented six major clades and fo ur monogeneric groups identified in earlier companion studies (an Afri can group, a South-east Asian group, a New Guinean group, an Australas ian group, an Acomys group, a Micromys group and Apodemus, Millardia, Mus and Phloeomys). When these companion studies are included 136 spec ies and 67 genera were studied. Ten major clades were consistently sup ported by the data but apart from linking the South-east Asian and Aus tralasian clades, the data do not resolve their inter-relationships. T he Acomys-Uranomys-Lophouromys clade may be the sister-group to the re st of the Murinae. Otomys (Otomyinae) is considered to be a murine rel ated to the African group of genera. Of the ten major clades identifie d, only one (Mus) occurs significantly in more than one primary biogeo graphic region. It is suggested that following an early period of rela tively rapid dispersal from the place of origin, little further disper sal took place and subsequent evolution occurred within relatively con fined geographic areas.