DINOSAURS

Introduction Dinosaur means “terrible lizard” Characteristics of dinosaurs: Very diverse Herbivores and carnivores Bipedal or quadrupedal Terrestrial Built nests and laid eggs Varied skin types including scales, armor, feathers Probably warm blooded

Dinosaurs Lived 230 to 65 mya during the late Triassic to early Cretaceous Periods (including Jurassic) Fossils have been found on every continent Kingdom Animalia, Phylum Chordata, Class Reptilia

Flora and Fuana Other animals alive at this time included: small shrew like mammals, insects, amphibians, reptiles, crocodiles, turtles, sharks, fish. Plants: conifers, cycads, ginkgos, ferns

Orders of Dinosaurs Saurischia and Ornithischia

Saurischia Saurischia: “lizard hipped” survivors evolved into birds

Saurischia: Therapods Therapods: Tyrannosaurus Rex and Velociraptor – bipedal, carnivorous, scales and feathers, includes modern birds

Saurischia: Sauropods Sauropods: long necks, herbivores, quadrupedal, very large, weak teeth – Apatasaurous, Brachiosauris

Ornithischia Ornithischia: “Bird hipped” (all died during extinction, no living descendents)

Ornithischia: Thyreophora Thyreophora: “armored dinosaurs,” plates and spikes, herbivores, early Jurassic to Cretaceous, Ankylosaurus, Stegasaurus

Ornithischia: Ornithopods Ornithopods: bipedal & quadrupedal, could chew, running grazers, herbivores of N. America - Iguanodon, Maiasaura

Ornithischia: Ceratopsians Ceratopsians: horned-face, herbivores, beaked, large quadrupeds – Triceratops, Psittacosaurs

Pterosaurs Are not dinosaurs Flying reptiles First flying vertebrates 220 to 65 mya Ranged in size from small to large Many had hair, did not have feathers Leathery wings

Marine Reptiles Not dinosaurs Plesiosaur Long necks Marine predator Air breather Mosasaur Fierce aquatic predators Breathed air Relatives of snakes and monitor lizards

Marine Reptiles Ichthyosaur Resembled dolphins Air breathers

Phylogenic Tree

What happened to the dinosaurs? Cretaceous Extinction 65 mya Mass extinction of plants and animals Comet landed in Gulf of Mexico All terrestrial (non-avian) dinosaurs died due to climate change and lack of food Mammals, amphibians, and birds survived and thrived Cold blooded reptiles survived

Birds evolved from dinosaurs Prior to the Cretaceous Extinction, a small, light- weight Jurassic therapod began adapting to its environment This animal survived the extinction, one early species was called Archaeopteryx