Colorful and complex, mantis shrimp have a deceiving name. They’re not actually shrimp at all; they’re more closely-related to crabs and lobsters. Their other name is “stomatopod,” which is a bit of a mouthful, so that’s why people prefer to call them mantis shrimp. There are over 500 species of mantis shrimp in every size. The smallest are less than an inch, with the larger ones measuring over a foot. All of them are pretty violent, and obtain their prey either by smashing or impaling. The spearers have two sharp appendages that act as spears, while the smashers have club-shaped claws. Scientists have been studying these clubs for some time, and just discovered what makes them so strong.
Pretty as a peacock, with a powerful punch
The peacock mantis shrimp wields its clubs at fast as 50 mph. When those clubs come into contact with another shelled creature, like a crab, it has the impact a .22 bullet. Even the water around the clubs is affected and can get as hot as the surface of the sun. How does the mantis shrimp do it?
How this heavy-hitter critter is shaped is essential. Right above the club, there’s a structure formed like a saddle. It basically works like a bow and arrow, according to experts. The muscles pull on the saddle, bending it, and then when it gets released, all that energy and power shoots into the club. What the shrimp is made of also matters. The top layer of the saddle is made of a material similar to bone known as hydroxyapatite, which is made of calcium-phosphate. The bottom layer is biopolymer, so it’s both elastic and capable of absorbing shock. If everything was made of the bone material, the shrimp’s club would crack. Instead, with this two-layer structure and bow-and-arrow style of release, the mantis shrimp is able to punch up its enemies without breaking itself.
Seeing is believing
Peacock mantis shrimp are not only the champion boxers of the underwater world, they also have the best eyes. They actually have the complex eyes in all of the animal kingdom. Each eyeball has 12 photoreceptors, while humans only have three. This means the shrimp might be able to see a whole bunch of colors we aren’t aware of. However, they also don’t see subtle variations very well. They are able to move their eyes independently, like chameleons, so they can see prey wherever it might be trying to hide.
A pet, but a solitary one
Because peacock mantis shrimp as so colorful and relatively large, many aquarium enthusiasts are interested in keeping them as pets. However, because they are aggressive, they will eat pretty much anything else you have in your tank, which is fine if you only want to focus on them. For food, they eat whatever can be smashed, like hermit crabs, lobsters, shrimp, snails, clams, and so on. You’ll also see them using their clubs to burrow and dig into rocks to hide. They love hiding. Since peacock mantises are large, they need a large tank. In the wild, they can live as long as 20 years, so you should be committed. There’s a lot of conflicting information online about keeping this creature, so you should only consider if it you’re experienced with aquariums and know where to find the best info.
Featured image by: Tony Shih
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