BOZEMAN, Mont. Dog-sized dinosaurs that lived near the South Pole, sometimes in the dark for months at a time, had bone tissue very similar to dinosaurs that lived everywhere on the planet, according to a doctoral candidate at Montana State University.
That surprising fact falsifies a 13-year-old study and may help explain why dinosaurs were able to dominate the planet for 160 million years, said Holly Woodward, MSU graduate student in the Department of Earth Sciences and co-author of a paper published Aug. 3 in the journal "PLoS ONE."
"If we were trying to find evidence of dinosaurs doing something much different physiologically, we would expect it to be found in dinosaurs from an extreme environment such as the South Pole," Woodward said. "But based on bone tissues, dinosaurs living within the Antarctic Circle were physiologically similar to dinosaurs living everywhere else.
"This tells us something very interesting; that basically from the very start, early dinosaurs, or even the ancestors of dinosaurs, evolved a physiology that allowed an entire group of animals to successfully exploit a multitude of environmental conditions for millions of years," Woodward said.
Jack Horner, Woodward's adviser and Regents Professor of Paleontology/Curator of Paleontology at MSU's Museum of the Rockies, said Woodward's findings are consistent with other results from the museum's histology lab.
"I think the most important finding is that polar dinosaurs don't seem to be any different than any other dinosaurs in respect to how their bones grew," Horner said. "Dinosaurs have annual growth lines and those that don't have them are simply not yet a year old."
Woodward said she conducted her research after reading a 1998 study about polar dinosaurs. Intrigued by the study, she decided to review the findings and received a National Science Foundation grant that allowed her to travel to Australia last summer, set up a his
|Contact: Evelyn Boswell|
Montana State University