Biologists have long believed the common ancestor of all primates was a small, deliberate animal which used its grasping hands and feet to scamper along thin branches foraging for fruits and insects. They theorized that the leaping skills came later, after the proto-primate evolved into two distinct groups — wet-nosed primates like lemurs and dry-nosed primates that include monkeys, apes, and humans. However, the discovery of a perfectly preserved 52-million-year-old fossil seems to suggest that the first primate might have been leading an impressively acrobatic lifestyle, leaping from one tree to another.