The fiercest creature on Earth is likely the Mantis shrimp, which pulverizes it’s hard-shelled prey with incredibly fast and deadly strikes from its hammer-like appendage dubbed a dactyl club.
In a report published in Advanced Materials, researchers at University of California Riverside identified a unique structure that wraps around the shrimp's club like the strips of cloth boxers use to protect their hands. The findings are being used to develop ultra-strong materials for aerospace and sports industries.
Previous research showed that the dactyl club is a multi-regional composite made of mineralized chitin -- the same material found in the shells of insects and crustaceans --arranged in a number of unique structures. The exterior of the club, called the impact region, serves as hard, crack-resistant coating that enables the mantis shrimp to inflict incredible damage to its prey by transferring its momentum upon impact.
The new research uncovered how the smasher carries out such rapid underwater attacks, which can occur at speeds of up to 23 meters per second. The profile of the club, together with an adjoining region called the propodus, is a hydrodynamic teardrop design that reduces resistance due to drag. Owing to this teardrop design, the acceleration of the club is so great (greater than a 0.22 caliber bullet) that it shears the water, creating cavitation (bubbles that implode) to yield a secondary impact on the mantis shrimp's prey.
Interestingly, aerodynamic cycling helmets and golf clubs mimic this design in achieving high performance structures.
Sources: University of California Riverside; Advanced Materials, Vol 30 Issue 9
