Paedomorphosis (juvenile characteristics remaining in adults) is a really neat mechanism for producing radically different-looking animals in a short time. In

Paedomorphosis (juvenile characteristics remaining in adults) is a really neat mechanism for producing radically different-looking animals in a short time. In the short span of ~30,000 years, we've managed to turn wolves into corgis that look like puppies their entire lives. We ourselves are often said to be a result of paedomorphosis from other primates -- now with less hair, bigger heads, and weaker muscles.