By Jim Knox
When it comes to speed, the animal kingdom has its all-star team. From the Pronghorn’s 60 mile per hour sprint, to the Sailfish’s 68 mile per hour burst, to the Cheetah’s 70 mile per hour blur, animal speedsters impress us with a swiftness we track with amazement. Yet, what if there were a creature which could move with a swiftness beyond our capability to see? What would we call such a creature, and how would we begin to unravel its mysteries?
The Zebra Mantis Shrimp, Lysiosquillina maculata, is a species with startling abilities. Known as Stomatopods, the Mantis Shrimp superfamily comprises nearly 500 known species. At the top of the heap sits the 16-inch-long Zebra Mantis Shrimp, the largest known Mantis Shrimp, and a creature to reckon with. With a worldwide range encompassing a wide swath of the shallow regions of the Indo-Pacific, from East Africa to the Galapagos, to the Hawaiian Islands, this extra-large crustacean reigns. Not a true shrimp, yet sporting a hard shell made of chitin and calcium carbonate, like their crab and lobster cousins, the Zebra Mantis Shrimp possesses a suit of flexible body armor. With a black and whitish striped elongate body, a fanned tail for rapid propulsion, and an infamous complement of spearing raptorial claws, the shrimp is an ambush assassin without equal.
As an ambush species hiding in shallow sandy crevices and burrows, this Mantis Shrimp’s need for speed lies not in the sprint, but in the lunge. It’s very design reflects this. The shrimp’s elongated, raptorial claws are lined with long, sharp spines which can stab, grip, or impale prey—literally before they know what hit them. Possessing a spring, latch, and lever structure, the shrimp boasts a spring-loaded strike. With energy stored within the folded, resting posture of the spearing claws, the unfolding motion triggers the muscle-assisted spring mechanism which launches the claws forward at nearly 3 meters per second. Factoring in the drag of water, this is remarkably fast and yet, just 1/10th the speed of its smaller Mantis Shrimp smashing cousins which crush their hard-shelled crustacean and mollusk prey with calcified club appendages. Let’s consider this superpower more closely. The Mantis Shrimp’s crossbow-like spring confers the fastest punch in the animal kingdom. Striking out with velocities approaching that of a speeding bullet, Mantis Shrimp hit their prey at up to 30 meters per second. This blistering speed generates power on the magnitude of a tiger’s bite—1,500 Newtons of force. With portions of the strike exceeding 3 thousandths of a second, and our ability to track motion, the Mantis Shrimp is truly quicker than the human eye!
This speed delivers more than lighting strike capability to its fish or crustacean prey. Such nearly instantaneous displacement of water generates a hydrodynamic process known as cavitation. This formation of vapor bubbles within liquid at low pressure leads to the expansion and collapse of the bubbles which generate massive amounts of energy in the form of an actual underwater shock wave. Whether we’re talking spearers or smashers, we’re talking acceleration which generates enough power to kill prey without contact. Now that’s speed!
Yet a superweapon of such speed requires a targeting system to deliver its power. That’s where the Mantis Shrimp’s complement of amazing abilities is truly revealed. With the unmatched ability to express up to 16 visual pigments, as well as the ability to detect a far wider range of light and color than humans—including ultraviolet and polarized light, Mantis Shrimp possess the most complex visual receptors in the animal kingdom. Coupled with advanced independent upper and lower corneas separated by photoreceptors known as ommatidia, which aid in providing visual contrast, the Mantis Shrimp can move its eyes independently to track prey. Upon entering the field of view of the shrimp, the eyes lock into place, focusing on the prey.
With a lineage going back 340 million years in the fossil record, these creatures have both benefited from Mother Nature’s research and development, and stood the test of time. Such impressive abilities confer a huge survival edge to the Mantis Shrimp. With adaptations which match, and even exceed our technology, these primeval creatures show us that advanced capabilities may reside in ancient life forms. In order to discover what may be possible in our future, we must get better acquainted with species tracing their origins to the distant past. With movements approaching the speed of a bullet, and the most advanced vision in the animal kingdom, the Mantis Shrimp is a creature without equal. An underwater speedster which exceeds the ability of all terrestrial creatures, this small beast warrants a closer look…if only we could see the creature behind the blur.
Jim Knox serves as the Curator of Education for Connecticut’s Beardsley Zoo and as a Science Adviser for The Bruce Museum. A Member of The Explorers Club, Jim enjoys sharing his passion for conservation and education with audiences everywhere.
