GLOSSARY

Welcome to the glossary... where all is explained...

Amniote: A tetrapod that lays shelled eggs, such as reptiles and birds.

Amphibian: A class of vertebrate trtrapod. The majority return to water to lay eggs. Living examples include frogs and salamanders.

Archosaurs: A group of reptiles that came to prominence in the Triassic. They included a wide range of carnivores and herbivores and were the ancestors to the dinosaurs and birds, crocodiles, and pterosaurs.

Carboniferous: A division of geological time from 360 to 290 million years ago. Named after the extensive coal seams ('carbon') deposited at the time.

Clade: A related group of animals with a common ancestor, e.g. the dinosaurs all evolved from a single common ancestor, and are a 'clade'.

Diapsids: Group of reptiles with two openings each side of the skull behind the eyes. Includes the dinosaurs and archosaurs. The extra openings in the skull allowed for an increase in muscle mass, giving a strong bite.

Dinosaurs: Mesozoic terrestrial reptiles with upright gait.

Devonian: A division of geological time from 410 to 360 million years ago. Named for the rocks of that age in Devon.

Jurassic: A geological period from 210 to 150 million years ago.

Mass extinction: The name given to a period of especially high rates of extinction of species. Several such events are seen in the fossil record. Some palaeobiologists suggest that we are on the brink of another mass extinction today, caused by human activities

Mesozoic: 'Middle life'. A geological era from 245 to 65 million years ago, and including the Triassic, Jurassic and Cretaceous periods.

Nodosaurs: A name given to the large armoured dinosaurs of the Cretaceous, such as Ankylosaurus.

Ornithopod: 'Bird footed'. A name given to the herbivorous dinosaurs that dominated the Cretaceous, such as Iguanodon and Parasaurolophus.

Ornithischia: 'Bird hipped'. One of the main divisions of dinosaurs, in which two of the bones in the hip pint backward, as in birds. See also classification of the dinosaurs.

Palaeozoic: 'Ancient life'. A geological era from 600 to 245 million years ago, including periods such as the Devonian and Carboniferous.

Pelycosaurs: Early reptiles with a single opening each side of the skull behind the eye. Also called 'mammal-like reptiles' as they share some features with mammals

Plate Tectonics: The name given to the study of the major features of the earths crust, including the movement of the continents.

Prosauropod: A group of saurischian dinosaurs that were the ancestors of the sauropods.

Sauropod: 'Reptile footed'. A name given the the large herbivorous dinosaurs such as Diplodocus and Brachiosaurus.

Saurischia: 'Reptile hipped'. Group of dinosaurs in which one of the bones in the hip points forward. See also classification of the dinosaurs.

Tetrapod: A clade of vertebrates possessing four legs bearing toes. Includes amphibians, reptiles, birds and mammals. The evolutionary loss (e.g. snakes) or modification (e.g. ichthyosaurs) of some limbs has occurred in some groups.

Therapsids: A group of primitive reptiles

Theropod: 'Beast footed'. A carnivorous dinosaur, such as Tyrranosaurus or Deinonychus.