 The advantages of bipedalism were that it left the hands free to grasp objects (e.g., carry food and young), and allowed the eyes to look over tall grasses for possible food sources or predators, but it is also argued that these advantages were not significant enough to cause the emergence of bipedalism.Earlier fossils, such as "Orrorin tugenensis", indicate bipedalism around six million years ago, around the time of the split between humans and chimpanzees indicated by genetic studies.This suggests that erect, straight-legged walking originated as an adaptation to tree-dwelling.