Large reptiles were among the most successful life forms ever to inhabit this world. 140 million years ago, they ruled the earth, the air, and the water. At that time, human ancestors were no more than tiny creatures resembling shrews—preyed upon by larger and stronger lizards.
Then 65 million years ago everything changed. A meteorite six miles in diameter struck the Earth and caused an irreversible shift in the atmosphere. As a consequence, more than sixty-five percent of the species living on Earth at that time were wiped out. The age of dinosaurs ended. The evolution of mammals, which they had been suppressing for a hundred million years, began.
And what if that meteorite hadn’t happened? What would our world look like today?