Terror Birds

"T. Rex and Triceratops were gone. If you could survive, you now had the opportunity." That is the pivot point that gave rise to terror birds — the apex predators that ruled South America as an island continent for tens of millions of years.

Dr. Steve Brusatte, paleontologist at the University of Edinburgh, explains that these birds are officially known as phorusrhacids — a name so hard to pronounce that even specialists avoid it, hence the nickname "terror birds." They were flightless, feathered carnivores that traded the ability to fly for enormous size and power. Some of the biggest stood over eight feet tall and weighed hundreds of kilograms, making them the largest predatory birds ever to exist.

The Survivors Who Inherited the Earth

The terror bird story begins 66 million years ago with the asteroid impact that ended the age of dinosaurs. The rock — about six miles wide — hit the Yucatán Peninsula with the force of a billion nuclear bombs. It triggered a global nuclear winter: darkness, cold, collapsed food webs. Seventy-five percent of species died. The big dinosaurs — T. rex, Triceratops, the long-necked sauropods — were gone. They were too large, needed too much food, and grew too slowly to survive.