Researchers have discovered a new species of giant penguin which lived in what is now New Zealand between 66 and 56 million years ago during the Paleocene Epoch.
A team of scientists led by Gerald Mayr from the Senckenberg Research Institute and Natural History Museum Frankfurt, both in Germany, estimate that the penguin, dubbed Crossvallia waiparensis, would have measured about 5.2 feet in height—or as large as some adult humans—and weighed up to 176 pounds, according to a study published in Alcheringa: An Australasian Journal of Palaeontology.
This makes C. waiparensis one of the largest species of penguin ever known to have existed and means it is comfortably bigger than today's emperor penguins, which stand at around 3.9 feet in height.
The remains of the giant penguin were discovered in 2018 by amateur paleontologist Leigh Love at a site in North Canterbury—a region in New Zealand's South Island.
Love found the leg bones of a single individual—as well as some possible wing bones—which Mayr and his team used to identify the penguin as a new species.
"Because only the leg bones are known, it is, of course, difficult to reconstruct the exact appearance of the new species," Mayr told Newsweek. "However, other Paleocene penguins have very long, dagger-like beaks. We therefore assume that the new species also had a longer beak than extant penguins, which is probably due to the fact that these early penguins were predominantly fish-eating.
"The new species is one of the largest fossil penguin species described so far and one of the very few giant penguins, which is represented by a partial skeleton. Certainly, it was a flightless species with flipper-like wings, which already attained the upright stance characteristic of modern penguins. Unlike most modern penguins, however, it lived in a warm, subtropical environment. The glaciation of Antarctica took place about 20 million years later and the evolution of penguins is not directly related to cold climates."
The fossil site where C. waiparensis was found—known as Waipara Greensand—is rich in ancient bird fossils. Five different species of ancient penguin have been uncovered there, making it perhaps one of the most important sites in the world for these animals.
"The fossils discovered there have made our understanding of penguin evolution a whole lot clearer," Mayr said in a statement. "There's more to come too—more fossils which we think represent new species are still awaiting description."
Analysis of the C. waiparensis fossils showed that its closest known relative was another Paleocene giant penguin species known as Crossvallia unienwillia which was first discovered in Antarctica, underlining the ancient connection between the icy continent and New Zealand.
"When the Crossvallia species were alive, New Zealand and Antarctica were very different from today—Antarctica was covered in forest and both had much warmer climates," Paul Scofield, an author of the study from the Canterbury Museum, said in a statement.
Intriguingly, the researchers say that C. waiparensis is the "oldest well-represented giant penguin." The fact that two giant penguin species have been found from the Paleocene epoch suggests that these animals grew to large sizes early on in their evolutionary history.
New Zealand is well-known for having hosted large birds in the past—including giant eagles, giant penguins and the flightless moa.
"That New Zealand housed so many giant birds is due to its long isolation and the absence of mammals," Mayr said. "The island was free of mammalian predators for a long time, and it is a well known fact that many bird groups tend to lose their flight capabilities and attain a large size under such conditions."
"Large penguins were, however, not restricted to New New Zealand, and the genus [group of species] Crossvallia, to which the new find is referred, was first described from the Paleocene of Antarctica," he said.
