This group of saurischians, the sauropods,
includes the biggest dinosaurs of all. Throughout the Jurassic and Cretaceous
periods the sauropods inhabited all continents and evolved into dozens of
different species. In the Jurassic Period, they were the dominant herbivores on
Earth, but by the end of the Age of Dinosaurs they had been replaced for the
most part by armored, horned, and duck-billed dinosaurs. Paleontologists have
identified many different subgroups of the sauropods. All members walked on four
legs and had elephant-like bodies, long necks, long tails, and small heads.
Some, such as Diplodocus, were long
and slender. Others, such as Brachiosaurus,
were heavily built, with long front legs and a neck that craned up like a
giraffe's.--
Text by:Bob
Simon
