Baby mantis shrimps start their lives as predators with ultra-fast movements -- from the first moment they start hunting for food -- according to a new study focused on the mechanisms that help the shrimp accelerate.

The study, published this week in The Journal of Experimental Biology, shows that the larvae of the Philippine mantis shrimp, gonodactylaceus falcatus, develop ultra-fast punching appendages when they're smaller than a grain of rice.

Tiny spring-actuated mechanisms hidden in the shrimp's punching appendages allow them to accelerate their arms almost 100 times faster than a Formula One race car -- which lets them move fast.

According to the researchers, when a muscle contracts, elastic energy is stored in the locked joint. Once the latch releases, the exoskeleton retains its natural position and propels the shrimp forward.

Once the shrimp exhausts its yolk reserves -- energy from the egg it grows in -- and moves away from its nest, it immediately begins preying on organisms smaller than itself.

"They're producing amazing speeds and impressive accelerations relative to their body size, but they're not as fast as adults," lead study author Jacob Harrison said in a press release.

"Theoretically, they should be producing the highest acceleration, but we don't find that," said Harrison, a doctoral candidate in biology at Duke University.

The discrepancy from the theoretical expectation could be due to numerous factors, Harrison explained -- the larvae muscles may be too small to load a very stiff spring, or water resistance may be too high for the punches to reach speeds that larger shrimp reach.

"There are limitations of these spring and latch structures that we don't fully understand," said Harrison. "But whenever biology moves us away from theoretical models, it highlights some pretty interesting areas for us to learn."

Baby mantis shrimp are easier to observe because their exoskeletons are fully transparent while adult mantis shrimp have opaque exoskeletons.

Scientists are able to observe the movements of the exoskeleton in adult shrimp, but the inner-workings of their spring-latch mechanisms are nearly impossible to observe in action.

"One of the trickiest parts of researching spring-actuated mechanisms is that a lot of those elements are working inside the animal. We can look outside of the animal and see behaviors, measure the kinematics, dissect the animal, and say the mechanism looks like it works like this, but there are always levels of assumption," Harrison said.

"Transparency sets up larval mantis shrimp as systems where we can look at how each of these elements works in concert together. It removes assumptions and allows us to understand on a finer scale," Harrison said.

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