There were four-legged carnivorous dinosaurs

KNOWLEDGE / Classification of Dinosaurs


Scientists divide the dinosaurs into different groups based on the relationships between the individual groups. This classification is based on the characteristic features that characterize a particular group. Recognizing and defining the skeletal features enables scientists to unravel the relationships between the various species of dinosaurs. In order to show how the dinosaurs developed, a kind of family tree was set up, also called a cladogram. A simplified cladogram of the Saurischia and Ornithischia can be found in Figures 1 and 2.



The dinosaurs are divided into two main groups, which differ in the shape of the hip bones. Dinosaurs, whose hips resemble those of today's reptiles, are called Saurischia (lizard-hipped). Those dinosaurs whose hips resemble those of today's birds are called Ornithischia (bird's hips). The hips of all dinosaurs are made up of three bones. The iliac bone, the pubic bone and the ischium. The difference between these hip types will now be explained in more detail. All dinosaurs are also divided into so-called families. A list with an overview and description of the individual families can be found here.



The Saurischia (Lizard tank) are divided into two main groups, the Theropoda and the Sauropodomorpha. Figure 3 shows the illustration of a Saurischier tank. As with all dinosaur fish, the pubic bone points forward. The foot-shaped pubic process is found in some theropods. All pelvic bones of a dinosaur were paired.



TheTheropoda (Beastly animals) were two-legged (bipede) carnivores (carnivores) with sharp teeth and claws on their grasping hands, among others these were Allosaurus(Fig. 4) and Neovenator as well as their descendants, the birds (Aves). You can get an overview of the species with the Theropods diagram (Fig. 5)

TheSauropodomorpha (Lizardfish, Fig. 6) were large four-legged (quadrupede) herbivores (herbivores) with long necks, long tails and large barrel-shaped, massive bodies like the des Supersaurus (Fig. 7). The Sauropodomorpha lived in the Upper Triassic and Lower Jura, the Sauropoda from the Lower Jura to the Cretaceous Period.




The Ornithischia (Bird tank) were all herbivores and are divided into five large groups: Ornithopoda, Ankylosauria, Ceratopsia, Stegosauria, and Pachycephalosauria. Below this text you will find a representation (Fig. 8) of an ornithic basin. This pelvis, with its pubis pointing backwards and the prepubis protruding forward, was typical of the ornithics



The Ornithopoda (Birdweed)
They lived in flocks and were usually bipeds, although sometimes they walked on all fours. They included, among other things Iguanodon and also Othnielosaurus (Fig. 9).

The Ankylosauria (Armored lizards)
Animals of this taxon like Gastonia (Fig. 10) had a body, the surface of which was provided with an armored layer of bone plates. Some species also had lateral spines and a tail club, which they could use as a weapon of defense against the predatory dinosaurs. They ate low-growing vegetation.



TheCeratopsia (Shield lizards)
The Ceratopsia include, among others Triceratops (Fig. 11) and Centrosaurus. For the most part they had impressive ruffles and some species had huge nasal horns on their skull.

TheStegosauria (Plate lizards)
The stegosaursKentrosaurus or Stegosaurus (Fig. 12) had a rather small skull in relation to their body. They had large plates of bone or thorns on their backs and tails, and sometimes on their hips.

ThePachycephalosauria (Thick-headed lizards)
They were characterized by skull caps, which consisted of thick layers of bone. This group, which was named after him, included, among others Pachycephalosaurus and Stegoceras (Fig. 13).

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Graphics and illustrationsofRaul Martin

Graphics and illustrationsofScott Hartman