World's Fastest Muscle (In the tongue of a salamander)

We all know chameleons, especially for some of their performances, like the ability of changing color or for their special hunting technique.

While the ability of changing color is not so singular in the animal world (many fishes, cephalopods like octopuses and squids, or even other lizards have it), their technique of projecting an enormously long sticky tongue is regarded by many as very specific.

That's wrong, as exactly the same method of catching prey is employed by a group of salamanders from the Americas.

Moreover, a new research at University of South Florida found an unusual record for these animals: the giant palm salamander of Central America shoots out its tongue with the fastest speed developed by any known muscle in the animal world.

The species, Bolitoglossa dofleini, can shoot out its tongue at 18,000 watts of power per muscular kilogram, about twice more than the power output broken out by the previous record detainer, the Colorado River toad Bufo alvarius.

Bolitoglossa extends its tongue (which measures more than half of its body length) in about 7 milliseconds, 50 times faster than an eye blink. The research team employed high-speed video cameras and electrodes implanted in the salamanders' tongue muscles to check the animals' performances as they hunted live crickets.

The fact that the tongues were propelled outward much faster than by sheer muscle contraction made the researchers suppose there must be an unknown elastic tissue connected to the salamander's tongue that stores up the energy amounts required by the explosive projection.

The process can be compared to the stretching and shooting of a rubber band: the recoil occurs faster than the act of releasing a rubber band pulled taut. "The amount of energy doesn't change; it's just released faster," said lead researcher Stephen Deban.

Tongue-launching systems found in other species is formed by three components: a motor to produce energy, a spring to store it and a latch to control the unloading of the spring, but by now only the motor in the salamander system has been found. "What remains to be discovered are the anatomical structures that make up the spring and the latch" said Deban.

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