 |
 Allosaurus
was the biggest
meat-eater in North America during the late
Jurassic Period, about 154 to 144 million years
ago -- up to 38 feet long and 16.5 feet tall, and
weighed about 3,000 pounds. |
 Brachiosaurus was one of the tallest and largest
dinosaurs, standing 40 to 50 feet in height,
being about 85 feet in length, and weighing
between 33 and 88 tons. |
 Diplodocus
was one of the longer species of dinosaurs,
growing as long as 90 feet and as tall as 16 feet
at the hips. Its neck alone was as
much as 26 feet long, and its tail was up to 45
feet long. |
 Tyrannosaurus rex means "king tyrant lizard," a
name it received because of its very sharp teeth
and rather fearsome appearance. The largest
flesh-eating animal that has ever walked the
earth, Tyrannosaurus rex was up to 40
feet long, stood about 20 feet high and weighed
about 7½ tons. |
 Pterosaurs
"flying
lizards," were flying reptiles that lived
during the age of dinosaurs. Some were as small
as sparrows, while others were as large as an
airplane. They had large brains, long tails,
short necks, and long, narrow wings. |
 Rhamphorhynchus
This flying reptile
had a wingspan of up to 5.75 feet. It was
probably an excellent flyer, but rather clumsy on
land. |
 Smilodon
Saber-toothed tigers
are some of the best known and most popular of
all Ice Age animals, but were actually more
closely related to modern-day wildcats (pumas,
bobcats, etc.) than to tigers. |
 Ground Sloths
(Megatherium) were
large relatives of the modern two-toed and
three-toed sloths. The smallest species -- Shasta
Ground Sloth -- was about 9 feet long and weighed
up to 550 pounds (about the size of a modern
black bear). |
 Mastodons
are one of an extinct
group of primitive elephants. The name mastodon
originated from the fact that the grinding teeth
of these animals had large nipple-shaped
projections on the cross ridges. |
 Eohippus (Hyracotherium
spp.) Eohippus, which means "dawn
horse," is considered by many to be an
ancestor of modern horses. Some paleontologists,
however, believe that this animal may instead
have been a "cousin" rather than direct
ancestor. |
