Biogeographical correlates of population variance in the honeybees (Apis mellifera L) of Africa

Multivariate analyses of morphometric characteristics of worker honeybees from five transects through northwestern, northeastern, west central, southwestern and southeastern Africa yielded sequences of statistically defined morphoclusters (= subspecies) alternating with heterogeneous zones of introgression. All transects contain areas of significantly high variance. High intracolonial variance indicates localised genetic variation and out-cross matings. Regions of high intercolonial variance occur at and between subspecific boundaries. These are typical of transitions between, and rainfall-temperature discontinuities within, different ecological-climatological zones. They constitute areas of ecological instability amidst otherwise contiguous populations.