Birds were nesting in the Arctic during age of dinosaurs, scientists discover | Palaeontology

the North Pole The pictures of the bears and the polar clouds may cause, but 73 meters before, it was a land of dinosaurs. Evangelist fishermen now say these monsters share grass with a group of different birds.

The researchers believe that their discovery of more than 50 hole of birds from the formation of Prince Kreik in Alaska is the oldest evidence of nesting birds in the polar areas, which leads to a decline in history by more than 25 million years.

“The oldest evidence of polar nest [that lived about 46.5m years ago]Lauren Wilson, the first author of the University of Princeton, said.

More than 200 species of bird nest in the Arctic today, where the researchers said they are decisive members of the ecosystem, and help in basic tasks such as pollination and seed dispersion. The recent results indicate their presence is not new.

“These new fossils fill a big gap in our understanding of the development of birds,” said Professor Patrick Drukinmeleer, Director of the Alaska University Museum in the north and co -author of the study. It was published in the magazine Science.

While the first birds appeared in the late Jurassic, about 150 meters ago, the sensitive nature of the bones of birds means that these animals are rare in the fossil registry. “Before this work, with the exception of some feet traces, bird fossils were not known from Alaska,” said Druckenmiller.

The discovery included more than just good luck, as the team carefully drilled the bone in addition to washing them and washing materials from small sandy sediments to isolate small fossils, and many of them were less than 2 mm.

“It was literally like gold for gold, with the exception of bird bones, is our prize,” said Druckmiller.

Wilson added that many bones were fetuses or missionaries. She said that at least one type of bird belongs to a brief group now called Ichthyornithes, and would resemble the elderly seagulls, while the researchers also found at least one member of another extinct group called Hesperornithes: the chromosome birds covered with the teeth.

Many fossils of birds without teeth may resemble ducks. The team’s note is important because features such as teeth are the distinctive feature of the Mineorne, the group that includes all living birds and the latest common predecessors. It indicates that birds that nest in prehistoric in the Arctic were relatives of modern birds.

“The 73 million -year -old ecosystems have seen about six months of continuous daylight in the summer, during which it would have become very green.” As a result, there was an abundance of food. However, winter was cold.

“while [winters were] Not cruel like today, the population throughout the year will have to withstand frozen temperatures, accidental snowfall, and about four months of continuous winter darkness. “

Wilson said that the newly discovered fossils showed that the birds were multiplying in the Arctic, but said it was unclear whether they had spent the winter season there, adding that it is likely that some of them are at least a migrant.

Steve Bruce, a professor of craft science and development at Edinburgh University, did not participate in the work, said that while the excavations discovered by the team were “very small”, he narrated a huge story.

He said: “These fossils show that birds have already been an integral part of high legal lines societies for many millions of years, and therefore these societies are a long -term base for the history of the earth, and not the last ecological innovation in the modern era.”