A new fossil discovery in northern Alaska has changed what we know about ancient birds. Tiny bones found in the icy Prince Creek Formation reveal that birds were nesting in the Arctic at least 73 million years ago—around 30 million years earlier than previously believed. This surprising find shows that ancient birds were more adaptable to extreme climates than we ever imagined.
Ancient Fossil Clues from the Arctic
A team of researchers led by Lauren Wilson from Princeton University uncovered over 50 tiny fossil fragments from one of the coldest parts of the world. These pieces were found in thin rock layers in Alaska’s Prince Creek Formation—a place that used to be part of a coastal floodplain much closer to the North Pole than it is today.
The excavation took place in extreme conditions, with temperatures dropping below -30 °C. Scientists worked in tents and later sorted sediment back in the lab, carefully examining grains smaller than two millimetres. Among them, they found chick and embryo bones, which had a sponge-like texture. This texture is a sign of bones that were still growing, proving that these birds hatched and lived in the Arctic environment.
Birds and Dinosaurs in the Late Cretaceous Arctic
These ancient birds lived during the Late Cretaceous period, a time when the region was also home to dinosaurs like tyrannosaurs and horned ceratopsians. Fossils show that some of these dinosaurs also nested in the Arctic, making it a busy breeding ground for different species.
Today, birds in the Arctic either migrate or have special adaptations to survive the cold. But this discovery shows that their ancestors were already raising their young in high latitudes—without the modern features we see today, like migration patterns or thick feather coverings.
Missing Ancient Bird Types Reveal Evolutionary Secrets
Interestingly, the fossils did not include any enantiornithines, also known as “opposite birds,” which were a major group of birds during that time in other parts of the world. According to Gerald Mayr from the Senckenberg Research Institute, this suggests that these older bird types may not have been suited to cold environments.
Instead, the birds found in Alaska were more closely related to modern birds, possibly giving them an edge in surviving the Arctic’s tough climate. These birds may have evolved special traits that helped them live in extreme conditions, long before birds as we know them today fully developed.
Types of Birds Identified from the Fossils
The research team identified three main bird groups among the fossils. These included toothed birds similar to modern loons, gull-like birds, and early relatives of modern birds. Though we don’t yet know if these birds lived in the Arctic year-round or only came to breed during warmer seasons, the discovery proves they were nesting in the region—a major step forward in understanding how early birds lived.
A Glimpse into the Past—and Future Studies
Birds are an important part of today’s Arctic wildlife, whether they migrate in or stay through winter. This discovery shows that birds have played a similar role in Arctic ecosystems for tens of millions of years. Steve Brusatte, a palaeontologist at the University of Edinburgh, called it strong proof that birds were key members of Arctic communities even in the age of dinosaurs.
The discovery of ancient bird bones in Alaska’s Prince Creek Formation pushes back the timeline of Arctic bird nesting by 30 million years. It shows how early birds adapted to survive and breed in cold, high-latitude environments, sharing the land with dinosaurs. These tiny fossils provide a huge leap in our understanding of avian evolution, and future research could reveal even more about how birds developed their incredible ability to survive in extreme conditions.
FAQs
What did scientists discover in northern Alaska?
Scientists discovered fossilized bone fragments of ancient bird chicks and embryos in Alaska’s Prince Creek Formation, showing that birds nested in the Arctic around 73 million years ago.
How old are the bird fossils found in Alaska?
The fossils date back to the Late Cretaceous period, around 73 million years ago, making them 30 million years older than previously recorded Arctic bird nesting evidence.
What types of birds were identified in the fossils?
The fossils included toothed birds similar to loons, gull-like birds, and early forms of modern bird lineages.
Why is the absence of enantiornithines important?
Their absence suggests that more modern-like birds may have had evolutionary traits that helped them survive Arctic conditions, unlike these now-extinct ‘opposite birds’.
Did these ancient birds live in the Arctic year-round?
It’s uncertain, but the presence of chick and embryo bones confirms that these birds nested and raised their young in the Arctic, suggesting at least seasonal residency.
