Between 1978 and 1983 hominid skeletal remains were collected from the cave sites of Batadomba lena and Beli lena Kitulgala in Sri Lanka (formerly Ceylon). These are the most ancient specimens of anatomically modern Homo sapiens found thus far in South Asia, radiocarbon dates placing them in the Upper Pleistocene. Morphometric analysis of the remains of some 38 individuals from the two sites indicates that these populations were characterized by medium stature, moderate to pronounced cranial and postcranial robusticity, medium-size permanent tooth crown measurements, prognathic alveolar facial proportions, and low incidence of osseous and dental pathological conditions. Comparisons of these ancient Sri Lankans with other prehistoric skeletal series from South Asia and elsewhere support the hypothesis that muscular-skeletal robusticity was a significant physical adaptation of earlier hunting-foraging populations. A trend towards reduction of sexual dimorphism and development of more gracile body form and smaller teeth appears to have accelerated with the socioeconomic transition to food-production strategies involving agriculture and pastoralism and refinement of technologies for food procurement and preparation, as documented by morphometric studies of later prehistoric inhabitants of South Asia.