Bioceramics power the mantis shrimp's famous punch

October 18, 2018

Researchers in Singapore can now explain what gives the mantis shrimp, a marine crustacean that hunts by battering its prey with its club-like appendages, the most powerful punch in the animal kingdom. In a paper publishing October 19 in the journal iScience, they show that a saddle-shaped structure in the mantis shrimp's limbs, which acts like a spring to store and then release energy, is composed of two layers made of different materials. Measuring the composition and the micro-mechanical properties of the layers--which are mostly bioceramic and mostly biopolymeric, respectively--allowed the researchers to simulate how the saddle stores such large amounts of elastic energy without breaking.

"Nature has evolved a very clever design in this saddle," says senior author Ali Miserez, a materials scientist who studies unique biological structures at Nanyang Technological University in Singapore. "If it was made of one homogeneous material, it would be very brittle. It would for sure break."

Previous research from the lab of biologist Sheila Patek had examined the mantis shrimp's dactyl clubs--the appendages they use to attack their prey--and suggested that muscles alone couldn't be creating the amount of force with which the crustaceans strike. Other research had hypothesized that the saddle might be used to store elastic energy, but studying the structure and mechanical properties of the saddle was challenging. "The movement is so fast that people hadn't been able to focus just on the saddle itself, which is why we needed to study it by computer simulation," says Miserez.

His team analyzed the composition of the saddle, making micro-measurements of the materials' mechanical properties to develop a simulation of the mantis shrimp's strike. They found that the top layer of the saddle is composed mostly of a relatively brittle bioceramic similar to tooth or bone, while the underside contains a higher content of biopolymers, which are fibrous like a rope and therefore strong when pulled on. When the mantis shrimp's muscles and connective tissues load energy into the saddle, the top layer is compressed and the bottom layer is stretched, meaning that each layer is placed under the forces it is best able to withstand.

"If you asked a mechanical engineer to make a spring that can store a lot of elastic energy, they wouldn't think of using a ceramic. Ceramics can store energy if you can deform them, but they're so brittle that it wouldn't be intuitive," says Miserez. "But if you compress them, they're quite strong. And they're stiffer than metal or any polymer, so you can actually store a higher amount of energy than you could with those materials."

The researchers also performed a series of experiments using small strips of actual saddle structures that they cut with a powerful picosecond laser beam. They analyzed how forces were distributed when the strips were bent the way they are in the mantis shrimp and when they were bent the wrong way. When they were bent the wrong way, with the biopolymers compressed and the bioceramics stretched, the strips were less able to withstand strong forces, likely due to tiny fractures in the ceramic layer.

Miserez and his colleagues are continuing to study the structure of the mantis shrimp saddle and have even started 3D-printing some mantis shrimp-inspired springs of their own, which could potentially be used in microrobotics.

"From a fundamental science perspective, the mechanics of this structure are quite interesting," he says. "But what this design also shows is that you can make a very efficient spring--and you can make it out of ceramics, which are more efficient than other materials people are using now. You can use materials that you wouldn't have thought about based on your mechanical engineering knowledge."
This work was supported by the Singapore National Research Foundation (NRF) and by a Singapore International Graduate Award (SINGA fellowship).

iScience, Tadayon et al.: "Biomechanical Design of the Mantis Shrimp Saddle - A Biomineralized Spring Used for Rapid Raptorial Strikes"

iScience (@iScience_CP) is a new open-access journal from Cell Press that provides a platform for original research in the life, physical, and earth sciences. The primary criterion for publication in iScience is a significant contribution to a relevant field combined with robust results and underlying methodology. Visit: To receive Cell Press media alerts, contact

Cell Press

Related Mantis Shrimp Articles from Brightsurf:

Secrets of 'smasher shrimp' property ladder revealed
Mantis shrimps carefully survey burrows before trying to evict rivals, new research shows.

Invasive shrimp-sucking parasite continues northward Pacific expansion
Researchers have identified an invasive blood-sucking parasite on mud shrimp in the waters of British Columbia's Calvert Island.

Strianassa lerayi anker, new shrimp species from Panama's Coiba national park
Last year's expedition, part of the project to compare microbiomes of animals in the Pacific and Atlantic oceans, resulted in the discovery of several new animal genera and a species of mud shrimp named for STRI and post-doctoral fellow, Matt Leray

Microplastics in shrimp harmless to animal health and no effects on consumption quality
A study conducted by the UAB certifies that despite the presence of microplastics in deep-sea shrimp, the amounts detected do not cause any types of health problems.

Technique fishes valuable nutrients out of shrimp processing water
The seafood industry requires large amounts of water for food processing.

How do mantis shrimp find their way home?
New research in Current Biology indicates mantis shrimp use path integration to find their way back to their burrows after leaving to seek food or mates.

Ancient mantis-man petroglyph discovered in Iran
A rare rock carving of an insect found in the Teymareh site of Central Iran has been jointly described by a team of entomologists and archaeologists in a paper now published in the open access Journal of Orthoptera Research.

Powerful mantis shrimp pull punches in air for self-preservation
Mantis shrimps are able to fire off high power punches in water at the speed of a bullet, but it now turns out that they are nowhere near as fast in air, only striking with blows that are a tenth of the power at just 18km/h.

Cuttlefish eat less for lunch when they know there'll be shrimp for dinner
Cuttlefish can rapidly learn from experience and adapt their eating behavior accordingly, a new study has shown.

Tiny fossils, big findings: UAlberta paleontologists discover odd mid-Cretaceous shrimp
One of the most incomplete fossil records of marine life is being filled in by a new find by a team of paleontologists from the University of Alberta, Yale University, and the Smithsonian Tropical Research Institute -- with the discovery of hundreds of tiny comma shrimp fossils.

Read More: Mantis Shrimp News and Mantis Shrimp Current Events is a participant in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to