A new study shows that the mighty Tyrannosaurus rex‘s bite was far less than the bite of a much smaller modern dinosaur — a tiny Galapagos finch.
Researchers evaluated the crunching strength in the bites of hundreds of animals — living and extinct.
Supercomputers evaluated bite force and body mass to track evolutionary changes in jaw power in animal groups that included mammals, reptiles and birds.
Galapagos Finch Packs a Powerful Bite
Results show that finches (living dinosaurs) packed a bite that was unexpectedly powerful for such a small creature.
In fact, if a finch were scaled up to T. rex-size, the bird’s bite would then be 320 times stronger than that of its extinct cousin.
These new findings don’t suggest that T. rex didn’t have a devastating bite.
But rather that the force of a T. rex bite is unsurprising when evaluated in light of the animal’s body mass and the bite strength of its ancestors.
Body Mass Matters
Bite force is measured in Newtons, with 1 newton (N) representing the amount of force that can accelerate an object weighing 1 kilogram to a speed of 1 meter per second.
T. rex weighed about 8 tons and had a bite force of 57,000 newtons, which sounds pretty impressive.
In comparison, a finch’s bite force is only 70 newtons, but its body mass is just about 1 ounce (33 grams).
For T. rex, and most of the other species that the researchers examined, bite force came about through gradual evolution over time and drew its strength from the animal’s mass.
Bigger animals are expected to have strong bites, according to lead study author Manabu Sakamoto, a biological scientist at the University of Reading in the U.K.
But there are exceptions.
In some species, such as the finch, Sakamoto says the bite force was not as expected from their body sizes.
This hints that in Galapagos finches, evolution “sped up” to increase their bite strength out of proportion to their mass since the bite strength of their finch ancestors about 1 million years ago was much weaker relative to body mass.
Read the findings online in the journal Proceedings of the Royal Society B: Biological Sciences.