Hand Bone Morphology Of Macaca Mulatta In The Taihang Mountains

In the study of the anthropology and non-human primates, hand bone has been the focus of academics who have studied at domestic and abroad. As metacarpals are short, not easily deformed, and easy to preserve, some experts try to use certain metacarpal variables to establish discriminant function to identify the remains’ gender. The main purpose of this paper is to expand the studies of hand bones research of foreign human and non-human primates to Macaca mulatta in Taihang Mountains. Hopefully, it will provide basic information to the system evolution, early development and sexual differentiation of non-human primates, and at the same time, accumulate more data for basic theoretical research and resource protection of Macaca mulatta.Macaca mulatta in Taihang Mountains were 44 cases of metacarpals(14 male, 30female), 45 cases of metatarsals(14 male, 30female) and 32 cases of phalanges specimens(11 male, 25 female), including proximal phalanges, intermediate phalanges and distal phalanges. The measured data were analyzed by SPSS version 20.0 for Windows statistical software. Statistical method used ANOVA, multiple discriminant analysis, binary logistic regression and ROC analysis, etc. The main results are as follows:(1) The sex dimorphism of phalanges’ some variables is significant(P<0.01), of which male is much more significant than female. It is an effective way to identify individual’s sex with 5 phalanges’ length variables. It is similar to the mode of human phalanx’ sex, presumably mainly influenced by sex hormones before and after birth. The 10 phalanges length ratios constituted by 5 phalanx are not significant difference(P>0.05). The results suggest that: Macaca mulatta’ sex mode of phalanges length ratios is differente from the anthropology and non-human primates’. A more reasonable explanation is the difference of population and of sex hormone interference mechanism during early development.(2) The sex dimorphism of metacarpal is significant. Different bones result in different sex dimorphism. There are certain individual differences among variables and sides. The fifth metacarpal has the biggest sex difference(AUC=0.968). The length is the most accurate variable to identify gender in the 7 main variables of metacarpal. The average correct classification rate of the left metatarsal is 91.8% and the right metatarsal is 90.3%, with very small bilateral differences. The results suggest that the impact of daily activities on the behavior of skeletal growth and development is not great.(3) The metacarpal sex difference is greater than that of metatarsal. It is similar to the mode of human metapodial’ sex. The result suggests that the different mode between metapodial may relate to life habits, frequency of use, range of motion and flexibility.(4) Differente statistical methods have been applied to the hand bones’ sex dimorphism analysis of Macaca mulatta. The results which are largely identical except slight difference exit side by side and play a part together to make the results more clear and accurate. Binary logistic regression and ROC analysis might be more practical and sensitive, which are much more practical and effective in the sex discrimination for bone specimens.