Extinct Animals

OK, hop in your time machine and go back 67 million years or so to the Cretaceous period. Then find a Tyrannosaurus rex and challenge it to a race. Sounds crazy, huh? Could you really outrun a Tyrannosaurus rex?

By Alison Cooper

Learn more about the top 10 most mysterious creatures to disappear from the earth.

By Desiree Bowie

The megalodon was born as big as an adult great white and grew to weigh as much as 7 Tyrannosaurus rex. Learn all about the megalodon.

By Joy H. Montgomery

It isn't hard to imagine this scene even though dinosaurs haven't walked the earth for millions of years. Dinosaurs have captured our imaginations. These dinosaur articles have been written to lead you into the exciting world of dinosaur research and back to the "Age of Dinosaurs."

By the Editors of Publications International, Ltd.

A full grown Allosaurus could be up to 34 feet long, stand 9 feet tall and weigh around 3 tons. This dino was a monster who, scientists suspect, would even eat his own kind.

By Mark Mancini

Apatosaurus was a huge sauropod from the Jurassic period. And there's a debate that's been raging for decades about whether its genus should cancel out the Brontosaurus entirely.

By Mark Mancini

Brachiosaurus has been portrayed in popular culture many times, but the representations of this mysterious dinosaur are largely based on another massive dino called Giraffatitan brancai.

By Mark Mancini

Supersaurus was a dinosaur that truly deserved its name. It measured about 100 feet in length and lived in North America. This dinosaur lived on a diet that consisted mostly of chutes and leaves from the tops of trees.

By the Editors of Publications International, Ltd.

The 1964 discovery of Deinonychus in southern Montana was groundbreaking for many reasons, mostly because it helped prove that birds are direct descendants of dinosaurs.

By Mark Mancini

Dinosaurs became extinct at the end of the Cretaceous Period. How and why is a puzzle that paleontologists are trying to solve by studying fossils and rock formations. Learn more about the different extinction theories.

By the Editors of Publications International, Ltd.

Interest in dinosaurs soared to new heights in the 1990s, thanks largely to the blockbuster film Jurassic Park. So too did dinosaur discoveries. Since 1990, more than 100 new dinosaur genera have been described and named. Learn more about recent dinosaur discoveries.

By the Editors of Publications International, Ltd.

Since it was named in 1979 by John Horner and Robert Makela, Maiasaura has become one of the most famous dinosaurs. It has provided information about how it cared for its young and the early development of dinosaurs. Learn more about the Maiasaura.

By the Editors of Publications International, Ltd.

The Velociraptors in "Jurassic Park" were roughly the size of humans. In reality, they were about the size of an average turkey.

By Mark Mancini

Types of dinosaurs include the lizard-hipped dinosaurs and the bird-hipped divisions of dinosaurs. Both of these types of dinosaurs probably shared a common ancestor during the Middle Triassic. How else are these dinosaurs related?

By Mack Hayden

Barapasaurus is named for a word meaning "big leg" in a local dialect in central India. This large dinosaur was a herbivore with large flat teeth that are ideal for cutting or crushing vegetation. What did this dinosaur look like?

By the Editors of Publications International, Ltd.

Perhaps no other beast has been more wildly mischaracterized in popular culture than the crested predator Dilophosaurus.

By Mark Mancini

Although it may be long extinct, this quirky bird continues to amaze scientist. The latest discovery? An awesome "musket ball" weapon located on the tip of its wing structure. Could our world once again include this big, old flightless pigeon?

By Jacob Silverman