Penguins with yellow feathers and a bright red bill that lived more than three million years ago may be the missing link between modern day penguins and their ancient ancestors.
A team of researchers from Massey University discovered that the “dawn” crested penguin called Eudyptes atatu was an ancient ancestor of today’s crested penguins that are native to New Zealand. Interestingly, the country is home to many sea creatures as approximately a quarter of the 360 seabird species on Earth breed in New Zealand and about 10 percent of them are native to the area. “New Zealand is surrounded by highly-productive oceans that attract seabirds from around the world – forming a global hotspot of diversity,” stated Dr. Daniel Thomas who is the lead author of the study.
“Eudyptes atatu is the sister species to all living and recently extinct members of the crested penguin genus Eudyptes,” explained Dr. Thomas. The ancient penguin lived around 3.36 million years ago, was a little over 2 feet in height and weighed approximately a stone (6.35 kilograms or 14 pounds) which made it a little more than half the size of today’s Emperor penguin.
Researchers found the fossilized remains of the ancient species on the North Island of New Zealand (pictures can be seen here). They were able to unearth a skull, jaw, beak, wing, rib, and leg bones of the Atatu penguin. Dr. Thomas noted that the remains were “exceptionally well-preserved thanks to their dense bones” and that the newly discovered ancient species revealed how seabirds, such as penguins, were able to evolve into how they are in modern times.
Its bill was of particular interest as the ancient species “has a markedly more slender upper beak and jaw compared with other Eudyptes penguins,” explained Dr. Thomas, adding, “That deep bills arose so late in the greater than 60 million year evolutionary history of penguins suggests dietary shifts as wind changes re-structured southern ocean ecosystems.” In fact, the large, deep bill of today’s crested penguins would have evolved as recently as the last two to five million years.
They believe the shift happened when the body size of baleen whales changed drastically which caused a large amount of nutrient-rich water to alter the food chain in the ocean. This caused a huge increase in krill that ultimately created a large variety of whales to inhabit the area. Dr. Thomas noted that crested penguins were affected by the change in the food chain as well but not as much as whales were. “The historical absence of terrestrial mammals – with bats being the exception – may have encouraged the formation of seabird colonies in deep time and contributed to the modern-day seabird biodiversity hotspot,” he explained.
He finished off by stating, “This has been an exciting research collaboration to be part of. It has given us an important new window into the evolution of crown penguins,” as it is a very important part of the evolution of seabirds in New Zealand. “Our growing fossil record suggests it was an incubator of penguin diversity in which the first penguins likely evolved and later dispersed throughout the Southern Hemisphere.”