SCIENTISTS have discovered the earliest evidence of birds nesting in polar regions, pushing back the record by up to 30 million years, the University of Reading has announced.
Research published on the cover of this week’s edition of the journal Science shows that birds were raising their young in the Arctic 73 million years ago, the same time and place where dinosaurs roamed.
A team of scientists led by the University of Alaska Fairbanks–which also included researchers from the University of Reading–examined tiny fossilised bones and teeth which were recovered from an excavation site in the Prince Creek Formation in Alaska.
They identified multiple types of birds, including some gull-like birds, some similar to modern ducks and geese, and some similar to loons,
They also found that the birds were breeding in the region.
Prior to this study, the earliest known evidence of birds reproducing in either the Arctic or Antarctic was about 47 million years ago, well after an asteroid killed 75% of the animals on Earth.
Some of the new bones have skeletal features only found in Neornithes, the group that includes all modern birds. Like modern birds, some of these ancient species had no true teeth.
Lead author Lauren Wilson, now a doctoral student at Princeton University, said: “Birds have existed for 150 million years. For half of the time they have existed, they have been nesting in the Arctic.
“Finding bird bones from the Cretaceous is already very rare. To find baby bird bones is almost unheard of. That is why these fossils are significant.”
Dr Jacob Gardner from the University of Reading, a co-author on the study, said: “Determining the identity of fossils using separate individual bones is notoriously difficult.
“For the first time, we determined the identities of large numbers of fossils using high-resolution scans and the latest computer tools, revealing an enormous diversity of birds in this ancient Arctic ecosystem.
“Polar bird communities have deeper evolutionary roots than previously imagined.”
