Mantis shrimp, often referred to as “thumb splitters,” are well-known for packing an incredible punch. Their claw-like appendages can strike with incredible force, showcasing the remarkable power that these small marine creatures possess In this article, we’ll dive into just how strong mantis shrimp claws are and what allows them to generate such tremendous impact.
Anatomy of the Mantis Shrimp Claw
Mantis shrimp claws are complex structures optimized for damaging prey and defending against threats Two main types of claws are seen in mantis shrimp species
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Spearers – Have spiny, pointed claws used to impale soft-bodied prey like fish.
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Smashers – Have club-like claws for crushing hard shells of mollusks and crustaceans.
The smashers generate the most powerful strikes and are specially adapted to withstand incredible forces:
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A saddle-shaped structure at the base of the claw helps distribute energy from impacts to prevent fractures.
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The claw itself has regions of hard mineralized armor interspersed with shock-absorbing regions full of protein fibers.
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Accelerator muscle fibers contract extremely quickly to generate striking speed.
With these adaptations, mantis shrimp can unleash devastating blows without self-harm. But exactly how powerful are these strikes? Let’s crunch the numbers.
Measuring Strike Force
The peak impact force of a mantis shrimp strike was first scientifically measured by biologist Sheila Patek in 2004. Using high-speed video and instrumented aquarium walls, she analyzed strikes from the peacock mantis shrimp (Odontodactylus scyllarus).
Some key findings:
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Smasher claws closed at speeds up to 23 meters per second (around 50 mph).
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The claws decelerated from this speed in less than 3 thousandths of a second, generating a tremendous amount of force.
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Peak impact forces reached 1,500 Newtons, even though the shrimps themselves weighed only 18 grams.
To put that into perspective, if a human could hit with the same power relative to our size, we could theoretically knock over a stack of 10,000 bricks with a single punch!
Comparing the Power
Mantis shrimp blows deliver impact energies up to 370 times their body weight. Here’s how that compares to heavy hitters from the animal kingdom:
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Mantis shrimp: Up to 370 times body weight
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Kangaroo punch: Up to 103 times body weight
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Bullet ant sting: Up to 80 times body weight
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Boxer punch: Up to 60 times body weight
Only the trap-jaw ant comes close with strikes up to 250 times its body weight. But it uses a different mechanism relying on jaws that snap shut, rather than mantis shrimp’s muscle-powered arms.
Putting Materials to the Test
The forces involved in a full-powered mantis shrimp strike are so extreme that few materials can withstand them unscathed. Researchers have tested a variety of substances against mantis shrimp blows with fascinating results:
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Aluminum: Deep cavities and fractures formed.
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Carbon fiber: Shattered into fragments.
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Kevlar: Split open at the fibers.
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Even stainless steel showed cracking and deformation under repeated strikes.
The only man-made material able to reliably withstand smasher blows? Ultra-hardened glass designed for demanding industrial applications.
Natural Weapons in Action
With their jackhammer-like claws, mantis shrimp can swiftly crack open hard-shelled prey:
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Crabs and lobsters: Smasher shrimp break through the robust carapaces to access the meat within.
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Snails and clams: Spearer shrimp penetrate the calcium carbonate shells and pull out the soft body.
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Coral skeletons: Mantis shrimp burrow into live coral using repeated blows to make hidey holes.
Aggressive individuals may also wield their claws against neighbors competing for space in reef habitats.
Studying Extreme Forces
The incredible impacts generated by mantis shrimp have researchers fascinated. What can we learn from evolution’s design of these natural spring-loaded weapons?
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Materials science: The complex structure of mantis shrimp claws provides insight into shock absorption and fracture prevention that could inspire new materials.
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Medical treatments: Understanding the mechanisms protecting mantis shrimp could point to new ways to prevent repetitive stress injuries in humans.
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Protective equipment: There may be lessons from mantis shrimp biology for improving impact resistance in things like football helmets and body armor.
By revealing nature’s solutions for managing extreme forces, these small crustaceans have a lot to teach us. Mantis shrimp pack a mean punch, but they could also punch above their weight in terms of benefiting technology and medicine too.
Study finds that strikes through air are half as fast as strikes in water.
The mantis shrimp is famous in the animal kingdom for its fast, powerful hammer strike, on par with the force generated by a .22 caliber bullet. One might conclude that those strikes would be even faster and more formidable in air, given the lower density and less drag of the medium. But thats not the case, according to a recent paper in the Journal of Experimental Biology. Rather, scientists found that the animal punches at half the speed in air, suggesting that the mantis shrimp can precisely control its striking behavior, depending on the surrounding medium.
Mantis shrimp come in many different varieties: there are some 450 known species. But they can generally be grouped into two types: those that stab their prey with spear-like appendages (“spearers”) and those that smash their prey (“smashers”) with large, rounded, and hammer-like claws (“raptorial appendages”). Those strikes are so fast—as much as 23 meters per second, or 51mph—and powerful, they often produce cavitation bubbles in the water, creating a shock wave that can serve as a follow-up strike, stunning and sometimes killing the prey. Sometimes a strike can even produce sonoluminescence, whereby the cavitation bubbles produce a brief flash of light as they collapse.
Per a 2018 study, the secret to that powerful punch seems to arise not from bulky muscles but from the spring-loaded anatomical structure of the shrimps arms, akin to a bow and arrow. The shrimps muscles pull on a saddle-shaped structure in the arm, causing it to bend and store potential energy, which is released with the swinging of the club-like claw.
Kate Feller, a co-author of the recent study who is now at the University of Minnesota, had been conducting a physiological study of mantis shrimp in the lab while still at the University of Cambridge in the UK. The creatures really dont like those controlled conditions and tend to lash out, especially when exposed to air. Feller figured out how to hold the shrimp in such a way that their gills remained under water, even though the appendages they use to strike were exposed to air. Her Cambridge colleague and co-author, Greg Sutton, visited her lab one day and mentioned in passing that it might be interesting to measure the force of the shrimps hammer blows in air. And thus this latest study was born.
Feller and her collaborators experimented with six females and one male mantis shrimp. Each shrimp was partly restrained on a gimbaled platform in an aquarium that was partly filled with seawater. This was done to make sure that there were no changes in body posture. Thus mounted, the animals were placed in the aquarium, sometimes fully submerged, sometimes partially.
The scientists then gently poked each shrimp in the posterior with a fiberglass stick to get it to strike out defensively, all while using high-speed video to capture the movement. And no, the shrimp did not appreciate being poked. “I have a pretty epic photo of my bleeding hand over a white sink when one stabbed me during this process,” said Feller.
All told, the team analyzed 31 strikes in the air and 36 strikes in the water. It was not what Feller thought it would be. The analysis showed that the blows were not stronger in the air at all. The strikes were half as fast, averaging roughly 5 meters per second, or 11mph. In fact, Feller et al. In their paper, they said that the mantis shrimp’s kinetic energy output in air is about the same as a grasshopper’s leg, but that when it hits water, it has 10 times more power.