Lateral Functional Dominance in Behavioral Traits Observed in Five Populations of Inner Mongolia.

Abstract

A sample of 1768 participants was tested for seven different traits of lateral functional dominance (hand clasping, handedness, arm folding, leg folding, stride type, preferential foot, and preferential eye) in five populations (Oroqen, Ewenki, Daur, Mongol, and Han) from Inner Mongolia, China. The results are as follows. 1) Seven traits all show right dominance (RD) in Mongol. However, just arm folding of the seven traits shows left dominance (LD) in Oroqen and Ewenki. In addition, LD also present for hand clasping in Daur, and for hand clasping and stride type in Han. 2) Sexual characteristics are not obvious in the traits. 3) Significant ethnic characteristics are observed in stride type, preferential foot, and preferential eye. 4) Some relationships occur in the traits. Furthermore, leg folding has the mostly close correlation with other six traits, followed by between hand clasping and handedness, and, in the last place, preferential eye with other six traits. 5) From PCA and cluster analysis, it is shown that, compared with Oroqen that has relatively distinct distribution of RD and LD for most of the traits, Ewenki shows the most similar to Mongol, and the more to Daur and Han in the distributing pattern. On the whole, the result coincides with the known history data of ethnic origin of each population.