DINOSAUR
TRACKS

CLASSIFICATION   

SECTIONS

 GENERAL FACTS
  

 CLASSIFICATION


 ANATOMY


 NEWS and
 ARTICLES


 DINOSAUR
 PICTURES


 GLOSSARY


 ADVANCED TOPICS

 EXTINCTION
 THEORIES


 EXHIBITS


 FUN and
 ACTIVI
TIES


 DISCUSSION
 GROUPS


 CHAT ROOMS




SIMPLIFIED PHYLOGENY OF THE DINOSAURS


DINOSAUR GROUPS

All known dinosaurs are divided into two large groups: Saurischia ("lizard-hipped") and Ornithischia ("bird-hipped"). Most saurischians had forward-jutting pubic hip bones, while in ornithischians each pubic bone slanted back, parallel to the ischium.

There were two major saurischian subgroup: the carnivorous, bipedal theropods and the plant-eating, mostly quadrupedal sauropodomorphs.

Ornithischians (all plant-eaters) were divided into three main groups: birdlike ornithopods, armored thyreophorans, and horned or thick-skulled marginocephalians.