The age of the elephant rats.

Live Science describes a new sort of prehistoric monster – a bull-sized rodent with elephant-like tusks:

An amateur paleontologist first unearthed the skull of an extinct rodent, Josephoartigasia monesi, from a boulder on a beach in Uruguay. The stunningly well-preserved skull was about 20 inches (51 centimeters) long, suggesting the rodent could grow to 2,200 pounds (1,000 kilograms), the researchers calculated.

For comparison, the next largest rodent ever discovered, Phoberomys, may have weighed up to 1,500 pounds (680 kg). And the modern world’s biggest rodent, the capybara, can weigh a modest 130 pounds (60 kg).

To understand more about how J. monesi used its teeth, Philip Cox, an archaeologist at Hull York Medical School in England, and his colleagues analyzed the likely orientation and size of the animals’ muscles along the jaw.

They estimated the rodent could produce a bite force of about 312 pounds force (1,389 N) — equivalent to that of a tiger. Even more impressive, the force at the animals’ incisors, or third molars, could reach about three times that amount, at 936 pounds force (4,165 N).

Because chomping down on veggies wouldn’t require that level of force, the authors suspected the incisors had another purpose.