Results tagged “impact event”

About 65 million years ago, an asteroid or comet crashed into a shallow sea near what is now the Yucatan Peninsula of Mexico.

Oxygen in the atmosphere and ocean rose dramatically about 600 million years ago, coinciding with the first proliferation of animal life. Since then, numerous short lived biotic events -- typically marked by significant climatic perturbations -- took place when oxygen concentrations in the ocean dipped episodically.