
Title: Hawaiian boxer crab or pom pom crab (Lybia edmondsoni)
The place it lives: The Hawaiian Islands
What it eats: Shrimp, squid
Why it is superior: The pom pom crab grows to solely round half an inch (13 millimeters) vast, and its smooth exoskeleton means its armor is fairly ineffective. But regardless of its minuscule measurement, this pugnacious little crustacean likes to struggle and eat whereas clutching harmful weapons — sea anemones.
The pom pom crabs, also referred to as Hawaiian boxer crabs, carry tiny sea anemones in every claw and use them to spar with rivals. This anemone species, Triactis producta, is venomous — and the crabs wave the anemones round as a manner of defending in opposition to predators and catching meals.
However additionally they carry them throughout mini battles with one another.
In a examine of the habits revealed in 1997, researchers chosen 12 pairs of crabs — six males and 6 females — and pitted them in opposition to one another in a tiny crustacean gladiator area. The winner was the crab that retreated or fled the least.
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The movies confirmed that the crabs used the anemones extra for present than for contact. When the anemones did contact opponents, it gave the impression to be by chance. So why trouble wielding these anemones?
The researchers had numerous concepts, however there was little consensus. There have been a number of proposed (and contradictory) hypotheses. One was that the anemones are so poisonous to the crabs that they are too dangerous to make use of as weapons — their use might lead to extreme hurt to each fighters.
On the flip facet, they could really be unhazardous to the crabs, so there’s not a lot level to utilizing them.
Lastly, the anemones could also be so precious that it would not be value it for the crabs to danger damaging the anemones. They do know the crabs use the anemones to gather meals particles and eat from them. After they lose one of many anemones, the crabs cut up the remaining one in two, so it at all times has one in every claw.
Scientists are nonetheless checking out why the boxer crabs cling to the ocean anemones. What the anemone will get out of it’s nonetheless unknown.