Unlocking the secret to delivering devastating blows with minimal impact, researchers have discovered the unique exoskeleton architecture of the mantis shrimp’s club-like forelimbs.
Mantis shrimp are renowned for their ultrafast and powerful punches, capable of delivering shell-splintering volleys without causing major injury to themselves. Researchers have discovered that the exoskeleton of their club-like forelimbs is designed to filter out the most damaging pressure waves caused by a strike.
The mantis shrimp is a small, carnivorous crustacean known for its impressive fighting abilities and vibrant colors.
Found in tropical waters around the world, these tiny creatures pack a punch with their powerful claws, capable of accelerating at the speed of a .22 caliber bullet.
With over 400 species identified, mantis shrimps are a fascinating subject for marine biologists and enthusiasts alike.
The Science Behind the Shrimp’s Resilience
The peacock mantis shrimp (Odontodactylus scyllarus) is small enough to fit in one’s hand, yet it strikes with such speed that it creates imploding bubbles. The impact and implosions work together to inflict forces that can exceed 1,000 times the mantis shrimp’s body weight. Despite unleashing this power repeatedly, the predators do not injure themselves or break their clubs.
A Natural Shield
Scientists initially suspected that the resilience of the mantis shrimp might come directly from the architecture within the club’s armor. The layers of mineral-hardened chitin, a long chain of sugars that is the primary component of arthropod exoskeletons, rest above deeper stacks of chitin bundles. These deeper layers are rotated slightly with respect to the layers above and below, creating a helix-like corkscrewing shape called a Bouligand structure.
The Bouligand structure, also known as the helicoidal structure, is a type of crystal lattice arrangement discovered by French physicist Maurice Bouligand in 1935.
It is characterized by a helical or spiral pattern of atoms or molecules, resulting in a unique crystalline structure.
This structure is often found in certain types of 'cellulose' and 'collagen fibers'.
The Bouligand structure has been studied extensively for its potential applications in materials science and biology.
Experimental Evidence
To test this theory, Horacio Espinosa and his colleagues conducted experiments in the lab. They mimicked the pressure waves experienced by the mantis shrimp by firing laser pulses at aluminum-coated cross sections of the club exoskeleton. The results showed that the mineralized outer layers control the spread of tiny cracks from the strike impact itself, while the deeper helix-like layers can dissipate or neutralize the highest energy waves.
Inspiring Materials Science
The discovery has significant implications for materials science. The helix-like structure inside the mantis shrimp’s club appears to be a natural version of engineered materials designed to manipulate the propagation of sound waves. This ‘adds to the growing body of evidence that shows that they also naturally appear in biological systems, where they have developed through evolution for wave and vibration control purposes,’ says Federico Bosia, a physicist at the Polytechnic University of Turin.
A helix-like structure is a type of molecular arrangement characterized by a spiral or twisted shape.
This configuration is commonly found in DNA and proteins, where it plays a crucial role in their function and stability.
The double helix structure of DNA, discovered by James Watson and Francis Crick, consists of two complementary strands coiled together.
Similarly, proteins like alpha-helices exhibit a helical arrangement of amino acids.
Helix-like structures are essential for the proper folding and functioning of biomolecules.
Potential Applications
The exoskeleton architecture could inspire materials such as impact-resistant armor, protective coatings, and aerospace structures. Materials scientist David Kisailus is already developing applications for the helix structure inside the mantis shrimp’s club, using it to enhance the toughness of airplane wings, wind turbine blades, and hockey sticks.
A Treasure Trove of Blueprints
Kisailus believes that there are millions of species waiting to be studied for their potential to inspire high-performance materials. ‘I know that there are many, many blueprints out there just waiting to be revealed in nature’s plethora of organisms,’ he says.
- sciencenews.org | How mantis shrimp deliver punishing blows without hurting themselves
