 When examining the body-size vs. lifespan relationship, one also observes that predatory mammals tend to live longer than prey mammals in a controlled environment, such as a zoo or nature reserve.The explanation for the long lifespans of primates (such as humans, monkeys, and apes) relative to body size is that their intelligence, and they would have a lower intrinsic mortality.Progeroid syndromes are genetic diseases that are linked to premature aging.