There was once a giant frog that ate dinosaurs. Admittedly small dinosaurs, but still. Frogs tend to use their long sticky tongues to catch food – but not these guys. They had a bite comparable to that of tigers and wolves.  

Researchers have estimated that the now extinct Beelzebufo frog, which lived in Madagascar about 68 million years ago, had an extremely impressive bite, capable of crunching up small dinosaurs and crocodilians. Publishing their findings in Nature's Scientific Reports, they worked this out by measuring the bite of a fairly similar, albeit smaller, species of frog that’s still alive.

The South American horned frog, a popular pet due to its big appetite and comical appearance, is sometimes nicknamed the “Pac-man” frog because of its big smiling mouth. Unlike most species, these frogs have strong jaws and a powerful bite, thanks to their short, heavy bone structure and strong jaw muscles. This allows them to catch dangerous animals like snakes and rodents that often match them in size.

"Many people find horned frogs hilarious because of their big heads and fat, round bodies. Yet, these predators have given us a rare opportunity to learn something more about the biology of a huge extinct frog," said study author Sean Wilcox, a PhD candidate at the University of California, Riverside, in a statement.

The researchers measured the bite force of horned frogs using a custom-made force transducer. Essentially it told them how much force was applied to two leather-covered plates when a frog bit them. Frogs with head widths of 4.5 centimeters (1.8 inches) bit with the force of 30 Newtons (N).

"This is the first time bite force has been measured in a frog," said lead researcher Professor Kristopher Lappin, from California State Polytechnic University, Pomona. "And, speaking from experience, horned frogs have quite an impressive bite, and they tend not to let go. The bite of a large Beelzebufo would have been remarkable, definitely not something I would want to experience firsthand."

Using their findings, the scientists estimated that much larger horned frogs, with head widths of up to 10 centimeters (3.9 inches) could bite with a force of around 500 N.

"This would feel like having 50 liters of water balanced on your fingertip," said Professor Lappin.

Moving on to the extinct Beelzebufo frog, the researchers estimated that this beast would have had a bite force of 2,200 N – as strong as a lion’s jaw.

"At this bite force, Beelzebufo would have been capable of subduing the small and juvenile dinosaurs that shared its environment," said study author Dr Marc Jones, of the University of Adelaide.

A frog that could bite with the force of a lion and ate small dinosaurs, that's not terrifying at all.