APPEARANCE OF OSSIFICATION CENTERS OF THE LOWER ARM, WRIST, LOWER LEG, AND ANKLE IN IMMATURE ORANGUTANS AND CHIMPANZEES WITH AN ASSESSMENT OF THE RELATIONSHIP OF OSSIFICATION TO DENTAL DEVELOPMENT

This study examines the appearance of the secondary ossification cente rs in the lower arms, wrists, lower legs, and ankles of a cross-sectio nal sample of 20 infant orangutans and chimpanzees (15 of known age). The number of tarsal and carpal centers is analyzed relative to the de gree of M(1) development and the weight of individual animals. Variati on in the appearance of these ossification centers is discussed relati ve to these variables and others. In addition, a sequence of appearanc e is established for the carpal and tarsal ossification centers in the orangutan and data is presented on the status of these centers in a f etal and newborn gorilla. Study results indicate that 1) there is vari ation in the number of secondary epiphyses present in animals of simil ar ages; 2) tarsal ossification is completed prior to carpal ossificat ion in the orangutan; 3) there are indications of a relationship betwe en weight and the number of ossification centers present in animals of similar age; and 4) there appears to be no evidence of specific relat ionships between carpal and tarsal development and M(1) development. ( C) 1996 Wiley-Liss, Inc.