Who You Callin’ A Shrimp?
Don’t be fooled by its colorful façade and small stature: The peacock mantis shrimp is no featherweight.
Adorned in radiant blues, greens and reds, the peacock mantis shrimp is not your average crustacean. About 400 species of mantis shrimp scour the sea, and the peacock is arguably the most vibrant. But an ostentatious appearance isn’t this animal’s only quirk.
Even more impressive is its pair of powerful raptorial appendages, similar to those of its namesake — the praying mantis. The two hammer-like forelimbs have a strike so fierce they would give Thor a run for his money.
Found throughout the Pacific and Indian oceans, the mantis shrimp is a voracious predator. In just three milliseconds, it delivers a blow that pulverizes its prey.
“Their punch could break glass, depending on their size and the size of their enclosure; and if they hit you, it could open your skin all the way down to the bone,” says aquarist Katie Webster, who cares for the National Aquarium’s mantis shrimp. “They’re known as thumb splitters.”
Luckily, she’s never experienced that danger firsthand. In fact, Webster almost never has to place her hand in the water. Observing the mantis shrimp’s behavior helped Webster design special precautions for feeding and cleaning its exhibit.
She attaches the mantis shrimp’s food to a short pole before placing it in the water. If the shrimp doesn’t bash the food, he’ll simply grab it with a second pair of appendages.
In the wild, mantis shrimp typically feed on gastropods, crabs, mollusks, small fish and shrimp, but they won’t shy away from a larger meal. “They have even been seen fighting and eating octopuses,” Webster says. “They’ll go after things that are bigger than them — whether or not they are actually successful at capturing them is the question.”
After the wear and tear of delivering about a thousand bashes to unsuspecting prey, a mantis shrimp molts, shedding its armored exoskeleton and often hiding the remains.
“It could be that they don’t want predators to know they have a softer body,” Webster says. While the new shell does require time to set, the animal never loses its brilliant colors.
The mantis shrimp’s eyesight is also something of a marvel. It possesses a visual system unlike any other. Every color humans perceive is a combination of three color receptors: red, blue and green. With those, we can see approximately 10 million different colors.
Now imagine instead of three, you had a mantis shrimp’s 12 to 16 receptors. They can detect light from near-infrared to ultraviolet, a much greater range than our visible spectrum.
Colors allow us to visualize contrasts and interpret details in our environment. The mantis shrimp’s brain encodes color in an entirely new way, allowing it to more swiftly scan its surroundings and process information to identify potential predators or prey.
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