Dinosaurs may have lived in arctic conditions, study finds
New research based on northern China rocks suggests the creatures developed feathers to survive in an environment with large ice sheets
Contrary to popular images of dinosaurs roaming a steamy tropical planet, the prehistoric creatures may also have spent long periods living among enormous ice sheets where they evolved feathers to survive the arctic conditions, according to a new study by Chinese and French scientists.
Researchers studying volcanic rocks in northern China found that continental ice sheets might have reached as far south as present-day Hebei province about 124 million years ago, early in the Cretaceous period.
Judging from the deep intrusion by ice melt water in the rock formations, the scientists believe the world then featured an ice-capped landscape, with average annual temperatures as cold as today's polar regions.
The Cretaceous period has been regarded as one of the earth's hottest eras. Dinosaurs were "greenhouse" creatures living in a tropical environment.
However, Professor Xu Xing , one of the paper's authors, said the new findings suggested a different scenario. "We had thought the temperature might have dropped as low as it does today in northeastern China, but it turned out to be as cold as the polar regions," said Xu, a researcher with the Institute of Vertebrate Paleontology and Paleoanthropology at the Chinese Academy of Sciences.