TORONTO -- Some 66 million years ago, an asteroid crashed down onto modern-day Mexico, leading to the extinction of the dinosaurs and other species.
Nearly 150 million years before that, another asteroid hit what is now the Manicouagan Reservoir in central Quebec. Although this strike was less immediately devastating, there have been some suggestions that it could have indirectly contributed to extinctions.
New research suggests these two impacts might not be isolated events, but might in fact contribute to a larger cycle of mass extinction of land-dwelling animals.
In the video at the top of this article, Â鶹´«Ã½ Science and Technology Specialist Dan Riskin explains what researchers found when they analyzed 10 mass extinctions over the last 300 million years, and why their hypothesis leads to another mystery – this one involving volcanoes.
