A penguin that waddled across the ice 60 million years ago would have dwarfed the king and emperor penguins of today, according to the Associated Press. As indicated by fossils recently uncovered in New Zealand, the extinct species measured 5 feet 10 inches while swimming, surpassing the height of an average adult man.

The discovery, which the authors say is the most complete skeleton of a penguin this size to date, is laid out in a study recently published in Nature Communications. When standing on land, the penguin would have measured 5 feet 3 inches, still a foot taller than today’s largest penguins at their maximum height. Researchers estimated its weight to have been about 223 pounds.

Kumimanu biceae, a name that comes from Maori words for “monster" and "bird” and the name of one researcher's mother, last walked the Earth between 56 million and 60 million years ago. That puts it among the earliest ancient penguins, which began appearing shortly after large aquatic reptiles—along with the dinosaurs—went extinct, leaving room for flightless carnivorous birds to enter the sea.

The prehistoric penguin was a giant, even compared to other penguin species of the age, but it may not have been the biggest penguin to ever live. A few years ago, paleontologists discovered 40-million-year-old fossils they claimed belonged to a penguin that was 6 feet 5 inches long from beak to tail. But that estimate was based on just a couple bones, so its actual size may have varied.

[h/t AP]