Geology Reference
In-Depth Information
Saurischian dinosaurs
The
saurischian
dinosaurs had lizard-like hip structure, illustrated in Figure 20-6 on the
right. This group had two distinct branches of dinosaurs, or sub-orders: the
sauropods
and
theropods.
The sauropods were most common in the earlier part of the Mesozoic. They
were massive creatures, possibly the largest land animals ever to exist, and in-
cluded the
Brachiosauraus,Diplodocus,
and
Apatosaurus.
These creatures walked
on four legs, ate plants, and moved in herds.
The theropod group included that most famous dinosaur: the Tyrannosaurus
rex, or T-rex. Another theropod made famous by the movie
Jurassic Park
is
Velo-
ciraptor.
Theropods were bipedal and carnivores. The smaller theropods likely
hunted in packs. Birds later evolved from some of these lizard-hipped dinosaurs.
