01 April 2011

Salamander tongue speed

Also from Discover Magazine (and also a couple years old) -
Some species of salamander can shoot their tongues out so fast that scientists suspect it can’t be done by the direct application of muscle power alone...

Using data from high-speed video recordings of 96 feedings, the researchers measured the speed of the salamanders’ tongue thrusts as the animals ate crickets, termites, and other bugs. While the maximum speeds ranged from 6 to 15.7 miles per hour, the salamanders’ tongues achieved breathtaking acceleration—up to 450 g’s.

This is a feat impossible to achieve using only muscles. Instead, the researchers concluded, the animal must have a system composed of three parts analogous to the components of a crossbow: a muscle to produce energy over time, a spring to store the energy, and a latch to release the spring in an instant.

The scientists have identified the muscle, but the spring and latch remain to be definitively identified. The spring is probably tendonlike collagen tissue, and the latch that releases it is most likely another muscle, because the salamanders can vary the speed and distance as they snap at their prey.
I think the spring-loaded crossbow analogy also applies to jumping fleas, and maybe the mantis shrimp.

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