Humans and dogs are a classic example of two different species working together and enjoying each other’s company. But there are plenty of other friendships in the animal kingdom — or rather symbiotic relationships. You scratch my back, I’ll feed yours.

Hermit crabs & sea anemones

An ocean couldn’t keep this underwater duo apart. When an anemone lives on the shell of a hermit crab, it is exchanging protection for a meal — according to Geek.com, the pair shares food and in return the crab gets to “retreat into the shell and let the stinging tentacles of the anemone ward off an attacker.” The crab likes the deal so much, it will take an anemone with it from shell to shell.

Read: An Ancient Otter the Size of a Wolf

Oxpeckers & zebras (& rhinos)

In this case, stripes and solids go together. The oxpeckers, which are birds, eat ticks or other parasites off the skin of the zebras. “The oxpeckers get food and the beasts get pest control,” according to the New England Complex Systems Institute. “When there is danger, the oxpeckers fly upward and scream a warning.”

It seems like a perfect relationship, as long as the zebras are fine with being two-timed — the oxpeckers perform the same service for rhinos.

(Everybody wants a rhino friend, it seems: Here's video of an elephant trying to play with a white rhino.)

Coyotes & badgers

The animals that hunt together stay together. At least that’s how it seems for coyotes and badgers. According to the U.S. Fish and Wildlife Service, they work better as a team when they are hunting for prairie dogs and ground-squirrels. The canine is good at chasing the future meal and the weasel “can dig after prey if it heads underground into its burrow systems. … Together they are both faster and better diggers than the burrowing rodents they hunt.”

But in their relationship, these animals hold onto their independence: “Coyotes and badgers have a sort of open relationship,” the FWS says. “They will sometimes hunt together; but they also often hunt on their own.” That’s especially true in the winter, as the coyote and the weasel mostly just hang out when it’s warm. In the cold, the badger instead preys on hibernating animals.

See also:

These Crab Claws Are Stronger than a Human Boxer

The Mystery of Dead Horseshoe Crabs