What strikes with the force of a bullet, can shatter aquarium glass, has a painted shell to rival the most beautiful peacock, and sees even more colors than we do?
The mantis shrimp, of course.
A small crustacean that looks something like a lobster, the mantis shrimp can grow up to 6 or 7 inches (15-18 cm) long. He lives in warm tropical waters and comes in a lovely array of colors including blue, pink, green, and orange. Wary divers call them “thumb splitters” because of their ability to leave a nasty gash.
A mantis shrimp can strike with the force of a .22 bullet, and so fast you cannot see the full strike. He fells prey by using the claw-like forelimbs that grow from the sides of his mouth. These special claws act like coiled springs, and three muscles work together to wield them. One muscle presses the spring tight, another latches it into place, and a third releases the limb when it is time to attack.
While a hammerhead shark can be safely contained for our viewing pleasure, most aquariums refuse to keep mantis shrimp. In 2001, a single shrimp stowed itself away inside some coral, and thereby made his way into the Monterey Bay children’s aquarium. He skulked around the exhibit, devouring the other marine life, until he was captured. Yes, the mantis shrimp has trouble playing well with others. But that is not the only reason he is rarely kept in captivity. This petite crustacean is capable of breaking aquarium glass with one well-placed blow.
The mantis shrimp’s attack is so fast that it causes cavitation—the production of bubbles—around its prey. As these bubbles collapse, they release an incredible amount of energy. These collapsing bubbles generate heat and small explosions of light called sonoluminescence.
To our knowledge, mantis shrimp can see more colors than any other living thing. Dogs have two kinds of cones in their eyes for viewing color. They see a world of grays, blues, and yellows. People have three types of cones, giving us all the glorious colors of the rainbow. But the little mantis shrimp has sixteen different types of color cones in his googly eyes.
If a little crustacean that strikes like a bullet and looks upon a world of color that would befuddle our minds is on your list of critters to see, than you might get that opportunity. The Monterey Bay Aquarium in California is bravely bringing back a peacock mantis shrimp. This time he will be housed alone, and you can come and see him for yourself, from the other side of a shatterproof tank.
The mantis shrimp has a cousin called the pistol shrimp that doesn’t even need to hit its prey to kill it. Rather, this shrimp has a built-in “handgun” that shoots bubble “bullets.” His two pinchers vary in size, with one large and the other small. Each pincher has two claws. The large pincher has a claw on one side that cocks like a hammer on a revolver. When prey gets within range, the pistol shrimp cocks the hammer. When the shrimp snaps his claw shut (drops the hammer), a “bubble bullet” is fired at speeds up to 62 mph (100 km/h). This produces incredible energy that is enough to stun or kill his prey. Oh, and did I mention, the pistol shrimp is no bigger than your finger?
The pistol shrimp may lose his big pincher. If this happens, the smaller pincher becomes bigger, and takes the place of the missing big pincher. A new small pincher grows back where the large one broke off.
Pistol shrimp also have a symbiotic relationship with gobi fish. In this picture, you can see both a gobi fish and the pistol shrimp. Notice the size variation of the shrimp’s pinchers.
—The Editors
