The peacock mantis shrimp (Odontodactylus scyllarus) weighs roughly 50 grams. It strikes at 23 metres per second – faster than a .22 calibre bullet – generating up to 1,500 Newtons of force. Cavitation bubbles formed by the punch collapse to deliver a secondary shockwave, effectively hitting prey twice in one strike. The animal delivers this punishment across its four-to-six-year lifespan without shattering its own fist. Engineers want to know how.
The Animal and the Strike
Mantis shrimp belong to the order Stomatopoda, a lineage of marine crustaceans that diverged from other malacostracans 400 million years ago. Over 520 extant species exist, divided into “spearers” and “smashers.” The peacock mantis shrimp is a smasher, wielding a hammer-like raptorial appendage called a dactyl club to bludgeon gastropods, crabs, and bivalves until their shells crack. The club stores elastic energy in spring-like structures held by latch-like tendons. When released, the appendage accelerates at over 100,000 m/s², exceeding 10,000 g. Biomechanist Sheila Patek and Roy Caldwell measured these forces in a 2005 study in the Journal of Experimental Biology, establishing peak impact forces of 504 Newtons from the claw itself, with cavitation collapse adding over 1,000 further Newtons.
The question that drew materials scientists was not how the club attacks, but how it survives. “Think about punching a wall a couple of thousand times at those speeds and not breaking your fist,” said David Kisailus, professor of materials science and engineering at the University of California, Irvine, who has studied the mantis shrimp for over a decade.
Inside the Dactyl Club
In 2012, James Weaver and colleagues at the Wyss Institute for Biologically Inspired Engineering at Harvard, alongside collaborators at Purdue and UC Riverside, published a landmark paper in Science titled “The Stomatopod Dactyl Club: A Formidable Damage-Tolerant Biological Hammer.” Using synchrotron X-ray diffraction, scanning electron microscopy, and nanoindentation, the team mapped the club’s internal architecture.
The dactyl club has three regions. The outer impact surface is dense, highly crystalline hydroxyapatite – the same mineral in human teeth, but with greater crystalline order. Beneath sits the impact region, where mineralised chitin fibres follow a helicoidal pattern: each layer of parallel fibres rotates approximately 15 degrees relative to the one below, forming a twisted plywood structure called a Bouligand architecture. The third region, the striated zone, contains fibres in a less mineralised matrix that absorbs energy through elastic deformation.
The helicoidal arrangement is the critical innovation. When a crack propagates, each rotated fibre layer redirects it, forcing the crack to twist as it advances. This twisting path vastly increases the fracture surface area, consuming far more energy than a straight crack. The result is a material hard enough to shatter shell yet tough enough to resist catastrophic failure.
From Biology to Engineering
Kisailus’s group at UC Irvine published further findings in Nature Materials in 2020, revealing that the dactyl club’s surface is coated with a nanoparticle layer of intertwined organic protein and polysaccharide and inorganic calcium phosphate nanocrystals. These mesocrystalline particles, stacked like interlocking bricks, provide damping properties that outperform most metals and technical ceramics. The research was funded by the Air Force Office of Scientific Research.
Helicoid Industries, a spin-out from UC Riverside, has commercialised the helicoid architecture for composite materials. Over 14 years, with more than $14 million invested across six universities and 70-plus researchers, the company developed carbon-fibre laminates mimicking the mantis shrimp’s twisted fibre arrangement. Their published data claims a 74 per cent delay in catastrophic failure, 50 per cent higher impact strength, and over 100 per cent increase in energy dissipation versus conventional quasi-isotropic laminates. The technology integrates with existing composite lay-up methods.
In June 2025, NIST researchers published findings in the Proceedings of the National Academy of Sciences describing synthetic Bouligand structures tested by microprojectile bombardment. Adjusting pitch angle and layer thickness changed how the material absorbed impact energy, offering tunable design parameters for protective applications.
A February 2025 study in Science by Horacio Espinosa at Northwestern University added another dimension. Using transient grating spectroscopy and picosecond laser ultrasonics, the team found the mantis shrimp’s club does not merely resist impact through toughness – it actively filters harmful stress waves through phononic mechanisms. The layered patterns on the club’s surface selectively block specific vibration frequencies, acting as a shield against self-generated shockwaves.
Applications and Outlook
Potential applications include body armour replacing heavier ceramic plates, aircraft fuselage panels, vehicle armour, sporting helmets, and seismic-resistant building materials. A 2024 study in Advanced Composites and Hybrid Materials showed gradient-helicoidal laminates achieving a 52 per cent improvement in threshold force for critical impact damage, relevant to electric vehicle battery enclosures.
The challenge remains scale. The mantis shrimp achieves its properties through control from the nanometre to the millimetre – a range difficult to replicate industrially. Nature spent 400 million years optimising the dactyl club. Materials scientists have studied it for barely 15. The gap is closing, but it has not closed.
Sources:
1. Weaver, J.C. et al. “The Stomatopod Dactyl Club: A Formidable Damage-Tolerant Biological Hammer.” Science, 336(6086), 1275–1280 (2012). doi:10.1126/science.1218764 2. Huang, W. et al. Nature Materials (2020). doi:10.1038/s41563-020-0768-7 3. Espinosa, H.D. et al. Science (2025). doi:10.1126/science.adq7100 4. Chan, E. et al. Proceedings of the National Academy of Sciences (2025). doi:10.1073/pnas.2425191122 5. Ouyang, W. et al. Advanced Composites and Hybrid Materials, 7, 217 (2024). doi:10.1007/s42114-024-01037-8 6. Patek, S.N. & Caldwell, R.L. Journal of Experimental Biology, 208, 3655–3664 (2005). doi:10.1242/jeb.01831
This article is part of our Biomimicry and Materials Science series. For more on how nature shapes engineering, see our piece on spider silk and synthetic fibres.
