Sixty-six million years ago, an asteroid or comet struck Earth on what is now Mexico's Yucatán Peninsula, resulting in the mass extinction of countless dinosaurs. This event, known as the Cretaceous–Palaeogene (K-Pg) extinction, did more than inspire Hollywood to create a blockbuster franchise about resurrecting the so-called "terrible lizards." It fundamentally altered the course of evolution. Every type of life needed to find its own way — plants as well as animals.
This wasn't as simple as it might seem. The balance of life on Earth was dramatically upset by the extinction event. Though many surface plants and trees died, their seeds did not, and soon after the extinction event the Earth was once again verdant. Yet the large land animals who fed on Earth's plants and trees did not. It would take tens of millions of years before those evolutionary niches were filled again.
