The fossilized remains of a giant penguin have been found at Hampden Beach in southern New Zealand. The fossils, researchers believe, came from a 220-pound ancient penguin species that was about five feet, ten inches tall, the height of an average man. The newly discovered species is called Kumimanu biceae and is derived from the local words for “monster” and “bird.”

The species is believed to have lived during the Paleocene epoch 55 million years ago, making it among the oldest penguin fossils ever discovered.

Scientists estimated the penguin’s size based on the fossilized remains of wing and leg bones found in sedimentary rock. Researchers recently published their findings in the journal Nature, but it’s not the first time ancient penguin remains have been found. Fossils dating back 25 million years have been found in New Zealand, and some dating back 30 million years have been found in Peru.

These other fossils of ancient penguin species indicate these animals had longer beaks than their modern relatives, which they likely used to spear fish.

Kumimanu penguins had flippers, and they likely would have sat upright like modern-day penguins. However, they were not the familiar white and black they are today—instead, their feathers were brown.

Scientists believe penguins descended from cormorants, a group of aquatic birds that persist today, and later evolved and spread. The asteroid that wiped out the dinosaurs and sea reptiles made way for sea-diving birds like cormorants and penguins.

When Antarctica and New Zealand were subtropical, penguins would have shared the same environment as sharks, turtles, and other seabirds.

Scientists speculate that the Kumimanu became extinct about 20 million years ago soon after large marine animals entered their ecosystem. Large toothed marine animals such as seals or whales may have competed for food in the area or consumed the giant penguins as prey.