Mystery behind strength of mantis shrimp's super-strong claws unraveled

London, June 8 (ANI): In a new study, scientists have tried to find out what makes the peacock mantis shrimp, which comes equipped with two built-in hammers that can deliver swift and powerful blows and smash straight through another animals' armour, so tough.

Although they belong to the same groups, Mantis shrimps are not shrimps. They are, however, aggressive predators, New Scientist reported.

Additionally, some mantis shrimps can see circular polarised light, which is used to create 3D movies. The colourful patterns on their bodies reflect polarised light, which may also be used as threatening signals.

There are two types of mantis shrimps, with different modifications to their front claws. Some have turned the claws into spears to stab their prey, while others - like the peacock mantis shrimp - have turned them into clubs.

Peacock mantis shrimps can deliver one of the fastest blows in the animal kingdom. Their clubs can move at up to 23 metres per second, and accelerate at over 10,000 gs.

This means that they can deliver a force of about 700 newtons, which is equivalent to the weight of a 70-kilogram mass or even as much as 1500 newtons.

With a weapon like that, it comes as no surprise that they can batter through the shells of molluscs and crabs.

Larger peacock mantis shrimps have even been known to smash their way out of fish tanks. Moreover, the blows are so powerful that they cause cavitation - they create tiny bubbles in the water that instantly implode, delivering even more energy to their victims.

As for the clubs, the shrimps do eventually replace each club when they moult, but not before they have delivered thousands of powerful impacts.

David Kisailus at the University of California, Riverside, and his colleagues looked at their structure and found out that the head of the club is divided into three main layers.

The outer impact region is mostly made of a tough mineral called hydroxyapatite, which is also found in bone. The hydroxyapatite is arranged in neat crystals, making for a strong coating.

In the second layer, the hydroxyapatite is less organised. Beneath it is a layer of chitin, the polymer that crustaceans use to make their shells. The three layers differ in how bendy they are, so it's hard for a crack that forms in one layer to extend into the next, so cracks don't spread far.

The chitin is arranged in spirals, which means that any cracks in the chitin tend to grow in spiral patterns, which barely weaken the overall structure. (ANI)