January 25, 2013
Fossilized Teeth Help Lead To 20 Dinosaur Identifications
Lee Rannals for redOrbit.com — Your Universe Online
A few fossilized dinosaurs teeth have led researchers to help identify more than 20 species of small meat-eating dinosaurs.
A University of Alberta researcher spent six years combing through collections of fossilized teeth in order to make the discovery. Derek Larson said he looked through thousands of dinosaur teeth found in western North America.
“Derek was able to expand our identification of small, two-legged meat-eaters that roamed Western Canada and the US from seven species to at least 23,” Philip Currie, Larson's research supervisor and a paleontologist at the university, said in statement.
The researchers said these two-legged dinosaurs ranged from the size of a chicken to six feet long. In most cases, tooth fossils are all that remains of small dinosaurs.
“It´s the same situation you have in today´s world with the remains of small animals like weasels,” Currie said in the statement. “Because the bones are light and small in size, after the animal dies the bones scatter, and if they´re not covered by sand or mud they disintegrate very quickly.”
They have fossilized skeletons with teeth for some of the small meat-eaters, helping them with the identification process.
Troodon was a two-legged meat-eater that was about six feet in length and its fossils have been found in Alberta.
“We were able to link some previously unidentified fossilized teeth as being from relatives of Troodon,” Currie explained.
He said they were obviously similar teeth, but were not exactly the same. They ran comparisons with other species represented by teeth and bones, giving them a way to establish that other tooth samples also must have belonged to small dinosaur species that were previously unidentified.
They said the huge increase in the number of identified small meat-eating species shows that instead of a few species for many millions of years, there were many small meat-eating species, each of which existed for shorter time periods.
“Given that today there are more small animals than large, it´s really not surprising that during the age of the dinosaurs there were lots of small dinosaur species as well,” Currie said.
The researchers published their findings in the journal PLOS ONE on January 23, 2013.