Turtle Fossil Points to Warm Arctic Past

Geologists from the University of Rochester discovered a warm-weather turtle fossil in the Canadian Arctic that suggests once temperate or even subtropical temperatures at the poles.

Setting out to study the paleomagnetism of the region, the turtle was uncovered almost by accident in an area known to be rich with fossils. A previously unknown species, the fossil resembles modern tropical Mongolian freshwater turtles and suggests a much warmer climate than the current frigid temperatures in the Arctic. In conjunction with the Royal Tyrrell Museum of Canada, the turtle species was named Aurorachelys, or aurora turtle.

Animals were previously thought to migrate between Asia and North America in the Cretaceous period via a former land bridge that existed around the Alaska region. This fossil evidence points to a previous warm Arctic freshwater sea that existed about 90 million years ago, through which species such as this turtle could have migrated directly across the pole.

This warming is believed to be due to ancient volcanic activity pumping massive amounts of carbon dioxide into the atmosphere, creating a "super-greenhouse effect" with a warm Arctic sea free of ice.

These results were published in the February issue of Geology.

Source: ScienceDaily