My Science School

Owls don't have eyeballs. They have eye tubes or cylinders, rod-shaped eyes that do not move in their sockets as eyeballs do. Instead, owls have to move their bodies or heads in order to look around. Since moving their torsos would likely make noise that would alert their prey to their presence, owls have evolved to have necks that can spin up to 270° essentially silently.

But why favour neck-spinning over the seemingly simple eye ball-spinning method of looking around? Well, night vision requires large corneas that allow for light to be collected effectively even in the dark, which is why most nocturnal animals (like the slow loris or tarsier) have huge eyes. But owls have small skulls, so their big eyes couldn’t expand out. They instead developed into the rod shape of today’s owls. They aren’t alone though: some deep-sea fish (like the anglerfish) also have rod-shaped eyes for seeing in the dark. 

Picture Credit : Google 

Humans are the only animals on earth with chins. The chin could be a "spandrel" or evolutionary by-product. It may be the result of the human face shrinking over time as our posture straightened and our faces shortened, or a remnant from a period of longer jaws.

The chin isn’t just the lower part of your face: It’s a specific term for that little piece of bone extending from the jaw. While it may seem odd, humans are in fact the only animals that have one. Even chimpanzees and gorillas, our closest genetic cousins, lack chins. Instead of poking forward, their lower jaws slope down and back from their front teeth. Even other ancient hominids, like the Neanderthals, didn’t have chins —their faces simply ended in a flat plane.     

Picture Credit : Google