They seem like one more bodily detail to tend to without much benefit, and sometimes more detriment (breaking a nail or scratching oneself up, ouch!).
They seem like one more bodily detail to tend to without much benefit, and sometimes more detriment (breaking a nail or scratching oneself up, ouch!).
Same reasons monkeys have them; it helps with grabbing on to branches. The stiffness of the nail results in an increased grip strength, because the forces are blocked.