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Thanks gleeaikin.
Reptiles Enjoyed Warm Arctic
Temperatures Averaged at Least 57 Degrees
by Kenneth Chang
December 18, 1998
ABC News
[images here] 90 million years ago... On a frigid and barren island called Axel Heiberg in the Canadian Arctic, just 700 miles from the North Pole, scientists have dug up fossil bones of an extinct, cold-blooded reptile known as champsosaur. Like all cold-blooded reptiles, the crocodilelike champsosaurs relied on the sun to warm their bodies and could not survive freezing temperatures. Since they lived on Axel Heiberg, that implies Axel Heiberg wasn't freezing... "Ninety million years ago, we think it was similar to northern Florida or Georgia," says John Tarduno, a geologist at the University of Rochester in New York. Temperatures averaged close to 60 degrees Fahrenheit and could have consistently reached the 80s and 90s during summer. Today, snow falls on Axel Heiberg in summer, and winter temperatures routinely dip to minus 60. Although plate tectonics slowly move continents and islands, Axel Heiberg hasn't wandered far in the past 90 million years. The location appears to have been at or north of the Arctic Circle during its balmy phase... Based on the habitat requirements of similar living reptiles such as crocodiles, the researchers concluded champsosaurs needed at least an average temperature of 57 degrees Fahrenheit to survive... Analysis of the turtle fossils found on Axel Heiberg gave similar conclusions... Most paleontologists believe this period, in the middle of the dinosaur age, to be a warm one, but not that warm.The Dinosaurs Of Winter And The Polar Forests
by William R. Corliss
Science Frontiers No. 75
May-June 1991 In Antarctica, heaps of 3- million-year-old fossil leaves have been found within 400 kilometers of the South Pole. (Francis, Jane E.; "Arctic Eden," Natural History, 100:57, January 1991. Also: Peterson, Christian; "Leafing through Antarctica's Balmy Past," New Scientist, p. 20, February 9, 1991.) To all -- please ping me to other topics which are appropriate for the GGG list.
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