Humans Are The Only Animal With This Body Part

When we think about our body parts, there are many anatomical similarities humans share with other animals. Speaking of Research notes that we may look different, but humans, mice, and horses all have hearts, lungs, and brains that function in similar ways. So similar are we to other animals that nearly 90% of veterinary medicines used to treat animals are very similar to or the same as medicines used to treat human patients. Perhaps even more eye-opening is that we share 99% of our DNA with mice.

Yes, humans may be anatomically and physiologically similar to other animals, but there is one trait that is truly unique to the human race. No, it's not opposable thumbs or our extraordinary brains. And even other animals blush. This mystery trait is heavily associated with late-night television host Jay Leno. And it is the only part that Batman chooses to expose.

The body part that only humans have are chins. "It's really strange that only humans have chins," said James Pampush, current assistant professor of exercise science at High Point University and formerly at Duke University (via The Atlantic). "When we're looking at things that are uniquely human, we can't look to big brains or bipedalism because our extinct relatives had those. But they didn't have chins. That makes this immediately relevant to everyone."

The reason as to why we humans have such prominent chins has yet to be agreed upon. Some researchers recently debunked the theory that we need our chins to help with chewing food. "The development of the chin doesn't seem to have anything to do with resistance to bending stresses," said Nathan Holton, an anthropologist at the University of Iowa, to Live Science. "They're just not related."

There is also the discussed theory that the other parts of the human face have shrunk, making our chins appear more prominent. Another theory for the chin's existence is that we use it as a sexual ornament to attract potential mates. "The chin is one of these rare phenomena in evolutionary biology that really exposes the deep, philosophical differences between researchers in the field," said Pampush to The Atlantic. The evolutionary reason behind why humans have a chin has yet to be agreed upon. Pardon the pun, but until we agree upon the answer, this question will remain a real chin scratcher.