— Hop away toads, you've lost your title as the world's strongest animal. That honour now passes to the giant palm salamander Bolitoglossa dofleini, whose tongue explodes outward with more instantaneous power than any other known vertebrate muscle. At 18,000 watts of power per kilogram of muscle, the salamander, from the forest floors of Central America, is nearly twice as strong as the previous champ, the Colorado river toad Bufo alvarius.
The palm salamander's strength doesn't come from muscle power alone but from elastic tissue that researchers believe stores up energy before exploding on release. "It's kind of like stretching out a rubber band and letting it snap back, or shooting a bow and arrow," says biologist Stephen Deban of the University of South Florida in Tampa.
High-speed video revealed that plethodontid salamanders released their tongues at a rate faster than could be achieved through muscle contraction alone. Electrodes on the tongue then showed that the muscles contract for one-fifth of a second, or about 100 times longer than the actual firing time of the muscle cells (The Journal of Experimental Biology, DOI: 10.1242/jeb.02664).
Deban and his colleagues think that stretchy lengths of collagen tissue intertwined with the tongue muscles are the likely secret of the salamander's strength.