Non-metric traits: remarks on sex dependence, age dependence, and on intercorrelations among characters

Abstract

Interdependence among non-metric traits as well as their correlation with sex, age, and body size usually cause methodological problems in phenetic investigations. Based on data on four mammalian species (Microtus oeconomus, M. limnophilus, Lepus europaeus, Capreolus capreolus) studied by the author, and on data from the literature these problems were analyzed. Both the number and the coefficients of intercorrelations among traits were found to depend on sample size of individuals examined. They were larger in populations with progressive and faster body growth. The number of traits related to sex increased significantly with sex dimorphism across mammalian species. Age dependence of traits did not show a regular pattern within and among species. These results are discussed as to their implications for estimating morphological differentation within and among populations.