Mantis shrimp are formidable punchers. The oceanic animals assault prey with a club-like appendage that travels fast as a speeding bullet.
Surprisingly, the mantis shrimp can repeatedly pummel prey at Superman speeds without injury to their club. Recent research explains that the material mantis shrimp clubs are made of neatly dispels damaging forces accumulated by a sharp punch.
The secret of the mantis shrimp’s injury avoidance is not just good for the mantis shrimp, but holds inspiration for protective gear for people too.
Most mantis shrimp live in tropical seas between Africa and Hawaii. The type of weapon they poses, either a club or a spear, defines two major groups: smashers and spearers. Smashers use their appendages to crack open the shells of mollusks and other hard-shelled ocean dwellers. Captive mantis shrimp have even been known to crack the glass of their fish tanks!
A team of researchers from Purdue, University of California Riverside, and Universidad EAFIT in Columbia explored how mantis shrimp avoid injury from their repeated punching. When the shrimp pummel their prey at an acceleration of 10,000 Gs it generates punishing force waves.
The microstructure of the mantis shrimp exoskeleton holds the key to combating force waves generated from a hit. Clubs are made of a compound called chitin, which makes up the exoskeletons of other crustaceans and insects. Chitin fibers in mantis shrimp clubs are laid out in a spiral-staircase like arrangement. This unique pattern is able to neutralize some of the most damaging force waves every time a mantis shrimp throws a punch.
Force dampening chitin is not just great for mantis shrimp; its secrets could also be used in the development of body armor for people.
There is a whole design field that turns to nature to solve technical problems. Biomimicry, or biomimetics as it’s sometimes called, is based on the notion that evolution has had billions of years to come up with solutions to problems that humans also face. It holds that looking for evolutionary solutions can be a great brainstorming source for challenges like cooling buildings, developing adhesives, or creating protective gear.
It turns out mantis shrimp are not the first crustaceans to inspire armor for people. When considering how to protect joints, Canadian protective gear manufacturers, Mawashi, turned to lobsters for inspiration. Lobster’s tails are protected by overlapping panels of exoskeleton, which allows the lobster to curl up or unfurl their tails all while ensuring protection from would-be-predators. Mawashi took this overlapping panel arrangement to create highly flexible, but durable knee and elbow pads that move with the user.
The mantis shrimp research team hopes that the unique chitin structure of their subject’s clubs can also be used in the development of protective gear. All that club thumping may someday translate into practical solutions, like football helmets with advanced protection for the wearer.
The mantis shrimp research was published online in a paper entitled “Shear wave filtering in naturally-occurring Bouligand structures” on May 14th in the journal Acta Biomaterialia. doi:10.1016/j.actbio.2015.04.039