Based on close examination of thousands of fossilized fish teeth, a Harvard researcher found that, while the asteroid impact that killed off the dinosaurs did lead to the extinction of some fish species, it also set the stage for two periods of rapid evolution among marine life.

Based on close examination of thousands of fossilized fish teeth, a Harvard researcher found that, while the asteroid impact that killed off the dinosaurs did lead to the extinction of some fish species, it also set the stage for two periods of rapid evolution among marine life.