Page 60 - The Restless Earth Fossils

Marking turning points in evolution 5

and the Canadian provinces of southern Saskatchewan and
Alberta to north, and from central Kansas to the east and eastern
Idaho to the west. Sauropod giants like Apatosaurus, Diplodocus,
and the common, so-called “Jurassic cow,” Camarosaurus, wan-
dered along waterways that often cut across semiarid country
that was not too unlike an African savanna. Ferns and other
plants took the place of grass, which had not evolved yet. The
dominant predator, Allosaurus, 40 feet (12 m) long and armed
with 70 curved teeth and ferocious toe claws, probably hunted
in packs to bring down sauropod calves, stegosaurs, and other
veggie eaters.
Fossils from the Morrison Formation also include conifers,
ferns, cycads (trees with trunks like pineapple skin and fernlike
tops), and other important plants of that time, along with many
animals including crayfish, insects, clams, lizards, pterosaurs,
crocodiles, and frogs. Our distant mammalian cousins also turn
up in great numbers. A site in Como Bluffs, Wyoming, has pro-
duced many rodentlike early mammals.
In 1909, paleontologist Earl Douglass (1862–1931) set out
for northeastern Utah to find a dinosaur “as big as a barn”
for Andrew Carnegie, a wealthy man who wanted to create an
impressive museum exhibit. Douglass succeeded by finding an
amazing site that eventually yielded (after 15 years of work)
the remains of more than a dozen species of dinosaurs, includ-
ing one of the most well-known, Apatosaurus (formerly known
as Brontosaurus). But Douglass wanted to do more than dig
up dinosaurs: He wanted to share the wonder of what he had
found. He wrote in his diary, “I hope that the Government, for
the benefit of science and the people, will uncover a large area,
leave the bones and skeletons in relief and house them in. It
would make one of the most astounding and instructive sights
imaginable.”
The U.S. government adopted his idea. The site is now called
Dinosaur National Monument, located near Vernal, Utah.

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