From the PLEISTOCENE

The lost world of mammoths, saber-toothed cats, and dire wolves

- Charles C. Hofer

Los Angeles, California, is one of the world's most glamorous places. Movie stars and fashion models, musicians and superstar athletes can usually be found under the bright lights of the bustling, sprawling city. But right in the middle of this glitz and glamour is a relic left over from a prehistoric world when strange creatures still roamed the Earth.

The pits at La Brea bubble with tar-in a busy urban park! For tens of thousands of years, the La Brea Tar Pits trapped animals big and small, becoming a graveyard for creatures of a lost age. Over time, the tar pits have become a treasure trove of bones. Today, the vast collection at La Brea helps scientists unravel the mysteries of an ancient world.

The Age of Giant Beasts

Most of the fossils recovered from the La Brea Tar Pits date back to the Pleistocene Epoch, a period that began about 2.6 million years ago and ended around 11,700 years ago. During the Pleistocene, the world was a much different place. Ice ages came and went. Glaciers helped carve out many of the mountains and plains, rivers and lakes that we see today.

By the time the Pleistocene began, dinosaurs had been extinct for more than 60 million years. Mammals now ruled the planet-very, very big mammals! The Pleistocene was dominated by megafauna, a word that literally means "large animals." Megafauna such as mammoths, mastodons, giant ground sloths, and short-faced bears roamed the lands that would one day be called North America.

The megafauna reigned for a fairly short period, however. Earth's climate changed rapidly near the end of the Pleistocene. The last great Ice Age came to a close, glaciers receded, and the planet grew warmer. A mass extinction soon followed, wiping out many of the large mammals that characterized the Pleistocene. Nearly all the megafauna species vanished.