An ancient \"Megapiranha\" weighing around 20 pounds delivered a bite with a force more fierce than even the toothy Tyrannosaurus rex, a U.S. researcher says. Based on bite strength versus body size as found in modern piranhas, the Megapiranha of 10 million years ago could have had a bite force from 280 to 1,070 pounds -- 30 times its body weight -- and possibly more, University of Washington biology doctoral student Stephanie Crofts said. \"If our calculations are correct, Megapiranha was probably a bone-crushing predator taking bites of anything and everything,\" she said in a university release. T. rex is thought to have been able to bite with 3,000 pounds of force but that\'s nowhere near 30 times its body weight. Pound for pound, Megapiranha and its modern cousins black piranha have the most powerful bites among carnivorous fishes, living or extinct, the study published in the journal Scientific Reports said. \"We were surprised that in spite of their long history and infamous reputations that no one had ever measured their bite forces,\" study lead author Justin Grubich of the American University in Cairo, Egypt, said of piranha. \"When we finally started to get the data, we were blown away at how tremendously strong the bites were for these relatively little fish.\"