Humans and monkeys share a close evolutionary relationship. Monkeys have tails, which help them balance. Humans have tailbones but no tails. What are the likely explanations for this situation?


( can pick more then one)


1. Monkeys and humans share a common ancestor.


2.The tailbone became vestigial, and the tail disappeared because humans could balance on two legs


3.Grabbing things with their tails became difficult for humans, so their tails disappeared.


4.Monkeys rely on their tails more than humans, so monkeys have tails while humans don’t.


5.Monkeys and humans don’t share a common ancestor.