A snapping shrimp’s big claw is not for boxing prey, but it snaps its claw very quickly to create shock waves.
These shock waves are so powerful that the prey can suffer tissue and organ damage, which makes it easier for this shrimp to catch it and enjoy a festive meal.
However, researchers from the University of Tulsa and the University of South Carolina were puzzled why these bigclaw snapping appear unaffected by the shockwaves which they and other creatures of their kind constantly produce.
They decided to collect several bigclaw snapping shrimps and study them in their laboratory. The team observed an orbital hood on the head of each shrimp, which they suspected to be some kind of protective armor.
They removed the orbital helmets from some of the shrimps, while others were untouched. Then, they observed both groups, with each of them appearing normal as they engaged in their usual activities.
However, when the helmet-less shrimps tried to catch prey by using shockwaves, they reacted as if they were hit by a bolt of lightning. Some of them appeared lost and disoriented after the shock wave, with several even falling over.
Meanwhile, the snapping shrimps with helmets did not react at all after producing shock waves with their big claws. Upon close examination of their helmet, the researchers discovered that, aside from their sturdy material, there are holes in them where water exits to remove pressure from the shrimp’s eyes and brain.
Hence, the team concluded that the orbital helmets on these shrimps were biological armors to protect themselves from supersonic blows.