Most powerful bite ever relative to body size

The most powerful bite ever relative to body size was that of the giant prehistoric piranha species Megapiranha paranensis, which lived in Argentina during the Late Miocene epoch, approximately 8–10 million years ago. Using data obtained from living modern-day black piranhas (Serrasalmus rhombeus), its bite force has been estimated at 1,240–4,749 Newtons. In comparison, its body length is estimated to have been a mere 70 cm (2 ft 3.5 in) and its body weight just 10 kg (22 lb), meaning that relative to body size its bite was far more powerful than giant carnivorous dinosaurs like Tyrannosaurus rex as well as sharks and meat-eating mammals.

Megapiranha paranensis was first brought to official scientific attention in 2009, when it was formally named and described by a team of palaeontologists led by Alberto Luis Cione. However, the specimen upon which this new species was based, consisting of a premaxilla fragment containing several teeth, had actually been obtained during the early 20th Century, in Argentina's Ituzaingó Formation, but its significance as originating from a hitherto-undescribed species had been overlooked until Cione rediscovered it within the collection of the Museo de la Plata.