Saurischia

Saurischia
	Several species of Saurischian Dinosaur
Scientific classification
Kingdom:	Animalia
Phylum:	Chordata
Class:	Sauropsida
clade:	Dinosauria
Order:	Saurischia; Seeley, 1888
Subgroups
	†Alwalkeria; †Eoraptor; †Teyuwasu?; †Herrerasauria †Maleriraptor; †Herrerasauridae; ; Eusaurischia †Sauropodomorpha; Theropoda; ;

Saurischia, (Greek for "Lizard hipped"), is one of two major groupings used to distinguish and classify dinosaurs, the other being Ornithischia. In the past it has been considered to be an order, but is now generally regarded as a clade. The name is derived from the method used to classify the animals, as dinosaurs classified under the saurischia branch are done so because they retain the ancestral bone configuration within their hips. All sauropodomorphs, one of the two great lineages of herbivorous dinosaurs, are saurischians as well as herrerasaurids.

Characteristics[]

The diversion between the two clades of dinosaurs developed in the late Triassic Period.

Classification[]

While the saurischia/ornithischia classification system is generally accepted among scholars and paleontologists, there does exist a minority theority proposed by paleontologist Robert Bakker that suggests classifying the theropods alone in their own clade, while grouping the sauropodomorphs along with the ornithischians in the second clade. In effect, grouping the carnivorous dinosaurs together, and the herbivorous dinosaurs together in a seperate order. This classification system identifies the carnivorous group as Theropoda, while classifying the herbivorous dinosaurs as either Phytodinosauria, or "plant dinosaurs", as suggested by Bakker, or as Ornithischiformes.

A 2017 study shows that saurischia is now paired up with ornithoscelida.