Mantis shrimp: cute but lethal
Our featuring character today is mantis shrimp (Odontodactylus scyllarus), a marine crustacean distributed around Indian Ocean and western Pacific.
It inhabits in coral reefs at between 3 and 40 meters deep. Its body is around 3 and 18 cm in length, it is completely adapted to live in tunnels and cavities, being one of the most lethal predators of its habitat.
Humans can only see a fraction of the entire light spectrum, however mantis shrimps can see from ultraviolet light to infrared and polarized. Every one of its eyes is subdivided in three, this means it can see an object in three different ways and perceive depth. Furthermore, the eyes work independently and they can rotate up to 70º. Anyway, mantis shrimp has one of the best visions of animal kingdom.
Deadly strike mechanisms
In addition, mantis shrimp is fully-armed. Their anterior extensions function as a whole so they can hit their prey with them. Mantis shrimp can reach up to 102.000 m/s2 of acceleration and more than 80 km per hour, the equivalent of 22-calibre gunshot acceleration. Because of the speed of the hit, it produces cavitation bubbles between their arm and the hit surface. These bubbles generate additional strength over their prey of 1.500 newton, so the prey is hit twice. Despite the first hit could fail, the shock wave generated by cavitation bubbles can have enough strength to knock out or even kill their prey. Cavitation bubbles generate, during a short period of time, light and a small increase of temperature similar to the surface of the sun, but it quickly dissipates.
Have a look at this video:
If you like to know more about mantis shrimp attack consult: S. N. Patek, W. L. Korff, and R. L. Caldwell (2004). «Deadly strike mechanism of a mantis shrimp». Nature 428: 819-820.