Population Composition of Five Subgroups of Koch Populations of Meghalaya, India: An Anthropodemographic Study

Anthropodemography uses anthropological methods to provide a better understanding of demographic phenomena. It refers to micro demography incorporating a fieldwork element. This study examines population composition of five subgroups (Chapra, Sanga, Satpari, Tintikiya and Wanang) of the Koch tribe of Meghalaya, India. According to Sundbarg’s classification of population, Chapra population is of regressive type, Sanga, Satpari and Tintikiya are of stationary type. On the other hand, Wanang population is of progressive type. Overall sex ratio is more or less 1:1 among the Wanang, which is in favour of males in the case of Chapra. Among the Sanga, Satpari and Tintikiya, the sex ratio is low. Mean live births and surviving children both are found to be lowest among the Chapra and highest among the Tintikiya. On the basis of marriage pattern all the subgroups of Koch population are highly endogamous. Infant, child and juvenile mortality rates in the populations covered under the present study are fairly high. Side by side, the admixture rate, calculated according to Lasker (1952), is very high in all the subgroups of the present study. Coefficient of breeding isolation suggests that differentiation in allele frequency due to genetic drift is not so important in all the subgroups, excepting Satpari population. Opportunity for selection is very high among the Chapra, which is in moderate intensity in the Sanga and Satpari. On the other hand, it is mild among the Tintikiya and Wanang. Keywords: microdemography, sub-populations, reproductive performance, opportunity for selection