Dinosaur

Dinosaur Footprints: Tracks Tell Prehistoric Secrets

Publication: National Geographic News   Date: March 10, 2003   View Article

Footprints impressed on the Earth millions of years ago are energizing the field of dinosaur paleontology which until recently has mostly relied on piles of old bones dug up from ancient sediments.

“Of course, there is much to be learned from a corpse, even one that has been dead for millions of years, but there is a limit after which you leave science and are left with speculation,” said Rich McCrea, a paleontologist at the University of Alberta in Canada.

Utah Dinos May Have Been Killed by Drought

Publication: National Geographic News   Date: December 20, 2002   View Article

Drought—not the perils of a muddy bog—may explain why millions of years ago hundreds of large, lumbering meat-eating cousins to Tyrannosaurus rex perished in what is now a dusty, rocky desert in southern Utah.

The site, named the Cleveland-Lloyd Dinosaur Quarry, is one of the world’s most prolific dinosaur fossil sources. It has yielded more than 70 partial skeletons, 12,000 individual bones, and single dinosaur eggs.

Fossil Leaves Suggest Asteroid Killed Dinosaurs

Publication: National Geographic News   Date: June 17, 2002   View Article

A team of scientists says evidence from fossilized leaves indicates that dinosaurs appear to have become extinct as a result of the catastrophic impact of an asteroid and not volcanic activity.

Dinosaurs, along with an estimated 70 percent of all life on Earth, are believed to have gone extinct 65 million years ago as a result of a series of dramatic temperature changes. The extinctions are known as the K-T extinctions because they fall on the boundary between the Cretaceous (geological symbol K) and the Tertiary periods.

Dinosaur Tracks Shed Light on Sauropod Evolution

Publication: National Geographic News   Date: May 30, 2002   View Article

Dinosaur tracks made on the edge of a coastal plain 163 million years ago in middle England are providing a team of researchers with new insights into the evolution and behavior of sauropods.

Sauropods are the group of plant-eating dinosaurs distinguished by their long necks and tails. They include some of the largest creatures ever to walk on Earth.

SuperCroc’s Jaws Were Superstrong, Study Shows

Publication: National Geographic News   Date: April 4, 2002   View Article

Chomp.

It weighed 17,500 pounds (7,938 kilograms), was 40 feet (12.2 meters) long, and probably ate dinosaurs for dinner.

Sarcosuchus imperator, an ancient relative of modern alligators and crocodiles that roamed the Sahara Desert 110 million years ago, had jaws of steel that no prey—not even small dinosaurs—could pry open, according to researchers.

Fossil of Dog Size Horned Dinosaur Unearthed in China

Publication: National Geographic News   Date: March 22, 2002   View Article

Researchers have announced their discovery of a very distant cousin to Triceratops, the well-known three-horned dinosaur with a massive bony protrusion behind its skull.

The discovery is an important piece in the evolutionary puzzle of the horned dinosaurs. Although they are considered one of the most diverse groups of dinosaurs, little is known about their early evolution.

Tyrannosaurus Rex Was a Slowpoke

Publication: National Geographic News   Date: February 27, 2002   View Article

That well-imagined nightmare in which a bloodthirsty Tyrannosaurus rex is chasing the family car down a lonely road in the red-rock desert as the children scream and the gas gauge hovers on empty and the dinosaur gnashes at the rear bumper is just that: a bad dream. T. rex was a slowpoke.

The most feared and revered of the dinosaurs did not have the leg strength to run very fast, if at all, according to a computer model developed by two experts in the mechanical movements of living creatures.

© 2008-2010 Collected Writings By John Roach