Issue Date: May 1, 1997
City: Grand Junction, CO
Quantity: 219,000,000
Printed By: Sterling Sommers for Ashton-Potter (USA) Ltd
Printing Method: Lithographed
Perforations: 11 x 11.1
Color: Multicolored

 

The World of Dinosaurs sheet depicts two scenes - one from Colorado during the Jurassic period (about 150 million years ago) and one from Montana during the Cretaceous period (approximately 75 million years ago.)

 

Some of the best-protected dinosaurs were the ankylosaurs. Covered with protective bony plates, lumps, and spines, these formidable-looking creatures are considered to be the “armored tanks of the dinosaur world.”

 

An ankylosaur that lived during the Late Cretaceous Period, Edmontonia (ED-mon-TOH-nee-uh) was discovered in 1928 when famed dinosaur hunter Charles M. Sternberg identified a skeleton found at the Edmonton (now Horseshoe Canyon) Formation in Alberta, Canada – hence its unusual name.

 

Edmontonia existed at a time when fierce predators terrorized the land. And although he was lacking in brain-power, he was well endowed with bony armor. Studs and plates fused together covered his back and tail – forming a single plate that was thick, tough, heavy, and impenetrable. Fearsome shoulder and flank spikes completed this protective covering.

 

Because his vulnerable spot was his soft underbelly, Edmontonia, like other ankylosaurs, crouched down and played dead when danger threatened. Predators could try flipping him on his back, but his well-armored body and protective spikes made this a difficult task. And since carnivores avoided injuries whenever possible, they would attack only when easier prey wasn’t available.