Rats are already scary at only two pounds. But thanks to a bunch of meddling scientists, we can now picture a rat that’s roughly the size of a small, active terrier.

Archaeologists from the Australian National University discovered the fossils of a new, nightmarish giant rat that’s roughly ten times the size of your run-of-the-mill subway vermin. The so called “mega-fauna” are the largest species of rat that ever existed according to the archaeologists, who discovered the animal in East Timor.

“The biggest one is about [11 pounds], the size of a small dog,” said the East Timor's project leader, Dr. Julien Louys. “Just to put that in perspective, a large modern rat would be about [one pound].”

The ANU team of archaeologists are in Southeast Asia studying the movement of Earth’s earliest known humans, who date as far back as 46,000 years ago. Those humans didn’t fear the giant rats—they ate them.

“We know they’re eating the giant rats because we have found bones with cut and burn marks,” said Dr. Louys.

The mega-fauna died off roughly one thousand years ago due to early technological developments by the humans, according to Louys.

“The funny thing is that they are co-existing up until about a thousand years ago,” he said. “The reason we think they became extinct is because that was when metal tools started to be introduced in Timor,” leading to quicker deforestation.

The “From Sunda to Sahul” project is hoping to understand the role human movement played on the development (or destruction) of ecosystems to help “inform modern conservation efforts.”

“Once we know what was there before humans got there,” Louys said, “we see what type of impact they had.”

At the very least, we know that early humans kept the world safe from giant, freaky rats that definitely wanted to eat us all.