Sharks are loners.

Sharks are often depicted in popular culture as being the lone wolves of the ocean, traveling solo and seeking adventure wherever they can find it. Turns out tha sharks can not only make shark friends but that those friendships can last for years.

Research conducted by Florida International University from 2011 to 2014 looked at 41 grey reef sharks off the Palmyra Atoll. The scientists were able to identify several social groups that clustered together, with some members going off to forage before returning to the same group. Even when sharks mixed with other groups, they tended to return to their own, signaling that there's some kind of preference.

So why do sharks do it? Scientists don't have a complete picture of that, but it's possible they're able to find more food more easily when sticking by a group than if they are off by themselves.