Penguins are known for looking cute and cuddly, but if the monster penguins of the Paleocene epoch were still around today, they might have developed a different reputation. As The Guardian reports, the fossil of a new species of one of these giant prehistoric penguins was recently discovered in New Zealand, and scientists say it would have gone head-to-head with many adult humans.

The bird, dubbed Crossvallia waiparensis, stood about 5 feet 3 inches tall and weighed about 175 pounds. For comparison, emperor penguins weigh up to 88 pounds and can reach 3 feet 8 inches in height. The prehistoric bird waddled the Earth some time between 66 and 56 million years ago—shortly after the mass extinction event that wiped out the dinosaurs and marine reptiles, which were probably its main predators.

An amateur paleontologist named Leigh Love discovered the creature's fossilized leg bones on New Zealand's South Island. From those fossils alone, a team of scientists from the Canterbury Museum in New Zealand and the Senckenberg natural history museum in Germany were able to estimate the penguin's height and weight and determine that it belonged to a previously undiscovered species. The large leg bones also indicate that the animal was more reliant on its feet for paddling through the water than the penguins of today.

Crossvallia waiparensis is massive by today's penguin standards, but it's not even the largest prehistoric penguin that we know of. When carnivorous reptiles began disappearing from the world's oceans, the waters opened up for new predators like penguins to flourish. Kumimanu biceae is estimated to have weighed about 223 pounds; Palaeeudyptes klekowskii may have weighed 253 pounds and stretched 6 feet 5 inches long.

[h/t The Guardian]