A newly published study has found that males of some of our earliest known ancestors were significantly larger than females. The pronounced difference in body size present in both Australopithecus afarensis (the East African species that includes the famous fossil “Lucy”) and A. africanus (a closely related southern African species) suggests the ancient hominins may have lived in social systems marked by intense competition among males, leading to the substantial size disparity among the sexes.
Early human ancestors showed extreme size differences between males and females
