The bizarre boxer crabs that rip sea anemones in two to use as 'gloves' to get food

Boxer crabs carry sea anemones to use as stingers to protect themselves
They also use the anemones to sting food which they bring into their mouths
They can rip an anemone in two if they only have one, because they can regenerate
If they don't have an anemone, they will fight other crabs to steal from them
The anemones are so crucial to the crabs' ways of life that when the researchers took the anemones away from them, the crabs struggled to gather enough food

Published: 12:34 EST, 7 February 2017 | Updated: 13:53 EST, 7 February 2017

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Researches have discovered that boxer crabs carry sea anemones around to use as stingers to protect themselves from predators.

The crabs carry the anemones around like pom poms and will even rip an anemone in two if it only has one.

They also use the anemone pom poms to sting food which they then bring to their mouths and eat.

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Researches have discovered that boxer crabs carry sea anemones around to use as stingers to protect themselves from predators. They also use the anemone 'pom poms' to sting food which they then bring to their mouths and eat

The researchers, based at Bar-Ilan University in Israel, also discovered that sometimes the crabs will hold the anemones and wait until they trap food morsels which they scrape into their mouths with their front legs.

The anemones are so crucial to the crabs' ways of life that when the researchers experimented with taking the anemones away from them, the crabs struggled to obtain enough food to eat.

According to the authors of the paper, the crabs deliberately keep the anemones to a small size, stunting their growth to 'bonsai sea anemones' so that they remain easier to hold.

If the sea anemones are taken away from the crabs, they grow much bigger.

When Yisrael Schnytzer, a PhD candidate and the lead author of the study, experimented with taking the anemones away from the crabs, the anemones increased by more than twice in size, their tentacles grew longer and the became brighter too

If a boxer crab only has one anemone, it can even tear it in two so that it has one in each claw.

It takes about 20 minutes for the crab to tear an anemone in two.

COULD SELF-HEALING ANEMONES CURE DEAFNESS?

When loud noises cause damage in our ears it is because the hair cells in the inner ear are affected.

Sea anemones detect passing prey with vibration-sensitive hair cells covering their tentacles.

Researchers at the University of Louisiana at Lafayette showed the creatures can repair these hair cells after being damaged.

In laboratory experiments, a cocktail of the proteins triggered rapid recovery of damaged cochlear hair cells - the cells of the inner ear that translate sound vibrations into nerve signals.

It hold the anemone with its claws and stretches it, using its legs to cut through the center.

Sen anemones can regenerate their bodies, so a half can become a whole animal on its own - and these anemones are clones of each other.

But if a boxer crab doesn't even have one anemone, it will often steal a piece of one from another crab.

The anemones are so important to the crabs that even small crabs will start fights with bigger crabs to steal an anemone.

The boxer crab that the team studied carries a species of sea anemone that has't been observed by itself in the wild.

But because these boxer crabs are always observed with them, the researchers say they may all obtain them by stealing from each other - and it could actually be how the anemones reproduce.

But there are three genetically different types of the anemones, so if they only reproduced through crab splitting, they would all be genetically the same.

Mr Schnytzer said that this suggests the anemones do also reproduce on their own, releasing eggs and sperm in the water while their held by the crabs.

Mr Schnytzer said that because they've never observed the anemones living on their own, the must need the crabs for some reason.