Roughly three million years ago, tiny penguins toddled around New Zealand, according to a new study. Eventually, these small creatures went extinct, but their relatives—known as little penguins, or korora—live on today in Australia, Tasmania and New Zealand.
Scientists recently discovered the extinct, diminutive penguin species, which they’ve named Wilson’s little penguin (Eudyptula wilsonae), and described it in a paper published last month in the Journal of Paleontology. They identified the species after studying two fossilized skulls—one that belonged to a juvenile and another that belonged to an adult—unearthed on New Zealand’s North Island.
The newly described species is now the oldest-known extinct little penguin, reports Bob Yirka for Phys.org. The finding suggests that little penguins have been consistent residents of New Zealand’s coasts for millions of years.
Because researchers only have the extinct animals’ skulls—and not their complete skeletons—they aren’t entirely sure how big the Wilson’s little penguins would have been. But they suspect the birds may have been similar in size to today’s little penguins, which weigh about two pounds and stand roughly 13.5 inches tall. The extinct birds, however, had slightly narrower skulls than the ones alive today, per the researchers.
The new findings shed more light on the lineage and evolution of existing little penguins, suggesting they originated in New Zealand, also known as Aotearoa. Scientists were also surprised to see just how little this lineage of “ridiculously cute” penguins has changed over time, despite big environmental shifts over the course of their evolution, per a blog post written by paleontologist Daniel Ksepka, a co-author of the study.
“This is important when thinking about the origins of these penguins, the evolution of the seabird diversity of Aotearoa and the dynamic environment in which they live,” says study co-author Daniel Thomas, a zoologist at New Zealand’s Massey University, in a statement. “For one thing, the climate has changed a lot over this time, and this lineage has been robust to those changes.”
Indeed, little penguins are still thriving—mostly. The International Union for Conservation of Nature lists them as a species of “least concern” and estimates some 470,000 of the creatures are waddling around today.
However, some recent instances suggest human-caused climate change may be taking a toll on the hardy animals. Last summer, for example, beach-goers found the bodies of hundreds of little penguins on the coasts of northern New Zealand.
After some analysis, wildlife officials determined that the birds were severely underweight and had either starved to death or succumbed to hypothermia after failing to find enough food. Ocean surface temperatures are rising, prompting fish to swim deeper in search of cooler waters—and though little penguins are strong swimmers, they can only dive to a maximum depth of 100 feet.
Right now, researchers are considering how continued global warming might affect Zealandia’s flora and fauna by looking into the past. The skulls of the Wilson’s little penguins will now be examined by a team of researchers led by study co-author Alan Tennyson, the vertebrate curator at the Museum of New Zealand Te Papa Tongarewa, in an effort to study fossils of animals that lived in the region long ago, during the last time that temperatures were much warmer than they are today.
In the end, they hope to use the prehistoric data to create a “biodiversity forecast” of what might happen to the ecosystem in the future, as Thomas tells the NZ Herald’s Jamie Morton.
“With millions of years of environmental change now being compressed into just a few human lifetimes, rising temperatures are enabling tropical animals to expand their ranges, leading to potentially irrevocable changes in wildlife communities in Aotearoa and other higher-latitude locations,” he tells the publication.
The same team also recently discovered the largest-known penguin species on Earth, which weighed 340 pounds and wandered around New Zealand some 50 million years ago.