Digital Vision/Getty ImagesUnlike most newborn creatures, elephants look geriatric right out of the womb, thanks in large part to their loose-fitting, wrinkly skin. African bush elephants are pachyderms (based on Greek word that means \"having thick skin\"), a group of large animals like hippos and rhinoceroses. For starters, the scientists found that the crackled appearance of elephant skin, is not a sign of aging or skin shrinkage, as is often the case with other species. Elephant skin, unlike human skin, is resistant to shedding, so the layers – particularly the super-tough top layer, the stratum corneum -- stick around longer before sloughing off. It also has a lot more keratin (the stuff that makes up fingernails) than human skin, so it's more durable.