Colobus are eaten regularly by the common chimpanzee. Jane Goodall discovered that chimps hunt and eat smaller primates such as "Colobus" monkeys. She watched a hunting group isolate a colobus high in a tree, block all possible exits, then a chimpanzee climbed up and captured and killed the colobus. The others then each took parts of the carcass, sharing with other members of the troop in response to begging behaviours. The chimps at Gombe kill and eat as much as "one-third of the colobus population" in the park each year. This was a major scientific find which challenged previous conceptions of chimp diet and behavior.