HAYLEY DUNNING
The Gateway (University of Alberta)

EDMONTON (CUP) — A new technique to date dinosaur bones developed by a University of Alberta researcher may prove that dinosaurs lived up to 700,000 years past previously recognized extinction dates.

The results challenge the view that dinosaurs died out in a relatively short period, around 65.5 or 66 million years ago. It means the idea of one huge meteorite wiping out the dinosaurs may need a radical revamp.

“It’s still possible that a meteorite or a series of meteorite impacts in a one- or two-million year period around that time did cause enough devastation to really stress animals like dinosaurs. But it wasn’t an instantaneous event,” explained Larry Heaman, the researcher behind the testing technique.

The researchers took a fossilized femur of a sauropod and, using a new uranium isotope dating method, found that it yields a date of only 63.9”“65.7 million years ago, meaning this particular dinosaur was alive up to 700,000 years after the mass extinction event.

Heaman collaborated with U.S. Geological Survey researcher James Fassett, who has been trying for nearly three decades to prove some dinosaurs lived past the Cretaceous-Tertiary Boundary, a worldwide sediment layer enriched in meteorite materials that traditionally marks the demise of the dinosaurs.

Although some dinosaur bones have been found physically above the Cretaceous-Tertiary Boundary, in a period called the Paleocene, most palaeontologists believed that they had simply been washed out from older sediments and re-deposited with younger ones.

“All these hints that this [fossil-bearing layer] is Paleocene have been met with controversy and skepticism. This is really the first direct dating that supports it,” Heaman said.

The new technique has previously been used to date ancient minerals, but this is the first time it has been used on bone. Its success lies in the ability to image and select specific areas that are suitable for dating. Heaman acknowledged that because it is so new, it would no doubt be met with some uncertainty.

Heaman first dated an older bone that was bounded by two volcanic ash layers that have very well defined dates, and found that the ages agreed. This helped prove the veracity of the technique, but Heaman says there are still ways to improve the technique, which he is trying to do on other dinosaur fossil samples.

“Our first strategy will be to go back to this site and look at a couple of other dinosaur bones. We are starting to look at some projects where we date velociraptor bones in Alberta and Mongolia to put them into a time frame,” he said.

The result of at least one individual outliving the traditional extinction of the dinosaurs will fuel research, as other scientists seek to use the technique to support or oppose the new idea. Palaeontologists will likely discuss how some groups may have survived an event long thought to have wiped a species off the face of the Earth.

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image: Matt Hirji/The Gateway