Studies on the parietal region of the cervid skull. II. The parietooccipital region in the skull of the fallow deer (Dama dama L.).

In contrast to the situation in roe deer (Kierdorf and Kierdorf, in press) and other cervid species, an os interparietale was missing in the fallow deer cranium. Absence of this skull element in Dama dama is regarded as an apomorphic character state. The area covered by the interparietals in Capreolus was occupied by the parietals in Dama. This condition (loss of interparietals, enlargement of parietals) is in accord with a trend seen in vertebrate evolution, that is, progressive reduction in the number of skull elements concomitant with enlargement of the remaining bones. Synostosis of the parietals in Dama started a few days post partum and was completed at about 7 to 8 months of age. In males, obliteration of the sutura parietooccipitalis commenced in adult life, whereas in females only closure of the central region of this suture was occasionally observed.