After the extinction of the Dinosaurs, for a brief period, Birds ruled the world before the rise of Mammals. The Phorusrhacid Family (known as “Terror Birds”) ruled South America which was isolated from the rest of the world for millions of years. Because of this, “Terror Birds” were dominant there during the late Miocene and Pliocene epoch (25 million years ago (mya) to 2 mya), while Mammals dominated other continents. Moreover, during the Great American Faunal Interchange, one “Terror Bird” went north to the Southeastern United States to compete with the Mammals there.
The Phorusrhacid Family was called “Terror Birds” because of their heavy sharp beaks. These giant flightless Birds would wait in ambush, and either slash or stab their prey, and then wait for the unfortunate victims to die. Instead of grasping and shaking their prey, “Terror Birds” used their fearsome beaks as hatchets for killing. They slashed downwards with their sharp barbed beaks on the skulls of their prey.
When the fossils of the first Phorusrhacids were found, people did not consider them to be those of Birds. In fact when the bones of Phorusracos were first discovered, scientists thought that they were from a large Mammal. Only when a skull of this “Terror Bird” was found, did people realize that She was a giant Bird. Meanwhile in Patagonia, a huge skull was determined to be a new species – Kelenken, who became named for a fearsome spirit of the Tehuelche people. As the tallest “Terror Bird”, She ran faster than the others. The newest member of the Phorusrhacid Family, Titanis made her way north to the United States, by swimming and island-hopping from South America.
During the Pliocene epoch (about two mya), “Terror Birds” went extinct. Some people have suggested the Great American Faunal Interchange for the reason, since many predatory Mammals went south. However, “Terror Birds” in regions where there were no predatory Mammals went extinct also. Perhaps climate change was the culprit, when many parts of South America became drier. Not much is really known about the demise of these Birds.
For a brief time, Birds ruled the earth. However what most people remember is the Age of Dinosaurs and the coming of the Mammals. Many forget about the Birds, and regard Them merely to be a place holder between Dinosaurs and Mammals. “Terror Birds” are largely relegated to an interesting sideshow.
“Terror Birds” urge us to pay attention, to discover things that we may have overlooked. For example, “Terror Birds” ruled a part of the earth that we may have not known much about. They tell us to give up our sketchy ideas and become more attentive to the details. “Terror Birds” give us a choice: Notice things closely or risk being stabbed.
1. “Terror Birds” are not related to “Monster Birds” (Dromornithidae) of Australia or Gastronis of the Paleocene epoch.