Some Late Triassic Species

Coelophysis-- A vicious little carnivore, it's an adept killing machine

Cynodont-- This mammal-reptile will eat it's own young to survive

Peteinosaurus-- An early pterosaur, it catches insects in it's pin-like teeth

Placerias-- A gentle herbivore, ready to use it's tusks in defence

Plateosaurus-- Clawed hands and a beak help it thrive

Postosuchus-- The biggest preditor of it's time

In the Early Jurassic period the herbivores and carnivores both increased in size. The sauropods grew staggeringly large, the carnivores got larger too but not as large as the herbivores.

There are two main types of dinosaurs, named from the configuration of their pelvic bones; bird-hipped and lizard-hipped. Sauropods and theropods are lizard-hipped; Stegosaurus is a bird-hipped dinosaur.

Some Early Jurassic Species

Allosaurus-- The lion of the Jurassic period

Brachiosaurus-- A giant, weighing more than 20 elephants

Diplodocus-- Up to 30 meters long, it has a whip-like tail

Anurognathus-- It feasts on bugs on the diplodocus

Ornitholestes-- A carnivore with 2 long clawed fingers

Stegosaurus-- Fierce display plates run down it's back

While huge dinosaurs dominated the land there were also large marine reptiles ruling the seas. There was the Ichthyosaurs, fish reptiles, with limbs modified into flippers, dorsal fins, and vertical tail flukes. The Plesiosaurs became numerous too. There were two kinds of plesiosaurs--the large short-necked pliosaurs which were the top predators of the seas and the long-necked plesiosaurs which probably fed on small fish and other small prey.

A Mystery

When marine reptiles are first found in the fossil record they are already specilized and it is difficult to trace their ancestry. There is little idea from which groups of land reptiles the Ichthyosaurs and plesiosaurs were decended.

Other reptilians of the middle-late Jurassic seas were the marine crocodiles. There were a couple different types of marine crocodiles, one of which was so adapted to life in the seas that their limbs had turned into flippers and they even had a fluke on their tails.

The Late Jurassic animals are bassed mainly on fossil finds from the Oxford Clay. The Oxford Clay was deposited in the shallow marine environment when the British Isles and part of Western Europe was on archipelago.

Some Late Jurassic Species

Cryptoclidus-- With Large flippers it glides through the sea

Eustreptospondylus-- A scavenger who can swim between islands

Hybodus-- This predator waits for its prey to surface

Liopleurodon-- Master of the Deep, with an impressive rosette of teeth

Ophthalmosaurus-- Large eyes help it hunt in deep dark waters

Rhamphorhynchus-- It scoops fish from the water with it's beak

This was a period of great change, new types of dinosaurs were appearing and flowering plants made their debut. The dinosaurs would be more abundant and larger and the flowering plants would become the most common plants on Earth. There was still no grasses, though.

Dinosaurs that could chew and fly

Ornithopods are herbivores, more plentiful and smaller than sauropods. The difference between them was that Ornithopods could chew their food, therefore needing smaller bodies . The Sauropods needed larger bodies so their guts could break down the food over several days. Bird-like dinosaurs called theropods, popularly known as raptors, also appeared. their arms were fairly long and more bird-like pelvis. The earliest known bird--Archaeopteryx-- comes from Germany. Most of these early birds look very primitive and some still have teeth. The largest animals to fly were pterosaurs. They seem, to our eyes, to be a mixture of bird and bat. Their long beaks remind us of birds, but they had membraneous wings.

Some Early Cretaceous Species

Iguanodon-- Chewing gives it an evolutionary advantage

Ornithocheirus-- This giant can fly 500m with a flap of its 12m wings

Polacanthus-- Armored all over except for its belly

Utahraptor-- Its sicle claw makes it a deadly fighter

Dwarf allosaur-- Terror of the Antarctic-the largest killer there

Muttaburrasaurus-- It anounces its presence with a loud trumpet

At the end of the Cretaceous Period, all the dinosaurs died out. There have been many ideas put forth as an explanation for this; two that are most likelly. The gradualist theory and the impact theory. The gradualist theory is that the extinction was due to climate change. The impact theory suggests that a meteorite hit the earth and triggered a nuclear winter. In addition at the end of the Cretaceous there were a lot of volcanic eruptions.

Some Late Cretaceous Species

Tyrannosaurus-- It can probably gulp up to 70kg of meet in one go

Ankylosaurus-- Its club-like tail is its secret weapon

Anatotitan-- A large duck-billed dinosaur, with mitten hands

Didelphodon-- A successful egg-stealing mammal

Quetzalcoatlus-- The largest known flying creature of all time

Torosaurus-- Its large head crest gives it a fearsom look