sentences:  Post canine enlargement has also been significantly positively correlated with basal metabolic rate, independently of body size.Larger primates tend to need larger teeth to process more food to meet the energy requirements of a larger body, but the evolution of postcanine megadontia is more likely due to the quality of the diet.The tough, “low-quality food stuffs" consumed by robust Australopithecines, coupled with their lack of food processing technology, lead to an enlargement of the occlusal surface of the molars.