press release

1. Piranha Crowned Biting Champ of Fish World
The black piranha (Serrasalmus rhombeus) has been crowned the pound for
pound biting champion of the fish world, by Guillermo Ortí, of George
Washington University.
The fierce fish ranks high in bite strength among all other vertebrates as well.
Its extinct cousin, the "megapiranha" may have put an even bigger hurt on prey
in the ancient Amazon basin.
The black piranha was measured to put up to 320 Newtons (a Newton is a unit
measuring kilograms per meter per second squared) behind its razor sharp teeth,
according to the study published in Scientific Reports.

2. The secrets to the piranha's powerful bite are its specially evolved jaw bones
and massive muscles. The muscle used to close the fishes' jaws can be up to two
percent of the fishes' weight. Imagine a 200-pound man with a pound of beef in
each cheek to get the idea of how much muscle that is.
Ortí scaled up from the black piranha and used fossil measurements to estimate
the bite force of the now extinct megapiranha (Megapiranha paranensis). The
deadly (but dead) predator could have put up to 4749 Newtons into a bite. That's
more than enough to shred flesh and crush bone.
Outsized jaw muscles allow the black piranha to exert bite force equivalent to
30 times its bodyweight, a feat unmatched in the natural world, according to
results of a finger-risking study.
Other animals like the great white shark, the hyena and the alligator can deliver
more forceful bites, but their crunching power becomes much less impressive
when viewed in relation to their overall size and weight, researchers said.
In fact, relative to their size, piranhas outperform even prehistoric monsters like
Tyrannosaurus rex and the whale-chomping megalodon, a massive shark that
preceded the great white, said the study.