You’d be hard-pressed to find any fish daring enough to voluntarily enter a top predator’s mouth, but that’s precisely what a humble fish called the cleaner wrasse does. These fearless fish swim directly into sharks’ intimidating teeth-filled mouths without so much as a second thought, and the sharks love it.

Many would assume that the shark would take advantage of the moment to score a free meal by chomping down on the cleaner wrasse, but just the opposite happens – it’s the cleaner wrasse that scores the free meal. These little fish eat the parasites that reside on sharks’ bodies, and this benefits the shark as a result.

The cleaner wrasse will also find its way inside of the shark’s mouth, and it’s in there that the little fish eats any leftovers that the shark hasn’t already swallowed.

It’s a bit of a head-scratcher that the shark doesn’t take advantage of a daring little fish such as the cleaner wrasse, but it’s wise enough to know that the removal of the parasites and leftover foodstuffs is good for its health. Consequently, it lets the cleaner wrasse do its thing and then live to tell the tale.

All the rest of those fish must think the cleaner wrasse has a death wish or something…