Postnatal Growth and Sexual Dimorphism in the Skull of the Japanese Macaque (Macaca fuscata)

Abstract

In order to know the relationship between postnatal growth and sexual dimorphism in the cranium of the Japanese macaque, 139 sex-known skulls of the species, which were graded into the nine “dental ages” by means of the dental eruption sequence, were measured on 17 craniometric items. The number of the measurements showing significant sex differences, all of which favored males, increased from two in infant sample (dental age 2) to 14 in adult sample (dental age 9). However, the increase was not monotonic. In dental ages 4 and 5, no linear dimension showed significant sex differences. Furthermore, the females exceeded the males in 47.1% of the cranial dimensions at dental age 4 ranging approximately 2.75 to 3.5 years, which was considered to be the period of the female adolescent growth spurt in the cranial dimensions. © 1994, The Anthropological Society of Nippon. All rights reserved.