When Marsh discovered the Brontosaurus it was thought to be a new dinosaur, but in actual fact it was actually the Apatosaurus, a dinosaur which had already been discovered by Cope. Despite the mistake the name had already gained much recognition and it became one of the most popular dinosaurs ever discovered. The name still lives on and the term Brontosaurus is still used over and above the correct term Apatosaurus.

The Apatosaurus was part of the Diplodocid’s, the ‘Double beams’, named after the twin extensions in the bones of their tails. Diplodocids were part of a branch of the larger family of Sauropods, ‘Lizard Feet’. The Apatosaurus existed in the late Jurassic era. They were four legged creatures of immense size, reaching 27m in length, which can be compared to the length of a tennis court. They had small heads supported by an extremely long neck, with a tail which was often even longer. Their dwelling place was mostly around flood plains and their teeth were peg shaped existing only at the front of the jaw, suited to there diet which consisted of plants.

Unlike other Diplodocids, the Apatosaurus was far heavier, a mass of many tonnes which would be equivalent to 4 or 5 elephants. Another mistake linked to this dinosaur was in relation to the creature’s head, which was believed to be like that of the Camarasaurus, whose head was box like, though soon enough the real head of the Apatosaurus was found and it was more like horse’s head, being long and low.

‘Roof lizards’, the Stegosaurs, are said to have first appeared in China, with the Tuojiangosaurus, however by the end of the Jurassic period the group included also the Kentrosaurus from East Africa, the Lexovisaurus from Europe and finally the Stegosaurus from North Africa. The Stegosaurus was the largest of the group, which grew to lengths of 30 foot and could be compared to the size of a bus.

The first fossils of this dinosaur were found in the western part of the United States. Since its discovery scientists have disagreed about the exact purpose and arrangement of the plates that existed along the dinosaurs back. The first theory was that they served as a form of protection, however this is unlikely as the plates were thin and lined with blood vessels, which were most likely covered with skin as opposed to bone.

The other theory is temperature control, where the plates served as radiators, helping the Stegosaurs keep warm when they turned toward the sun and cool down when they turned away. However Stegosaurs did have a form of protection, they were equipped with a mace like tail, which was made up of at least two long pairs of sharp, bony spikes, covered in horn.

The Stegosaurs dwelled mostly in open woodland, where they had access to plenty of plants, which would have had to be consumed in huge amounts to maintain their great huge mass. Like the spiky plates on the Stegosaurs, the brain of the dinosaur also created some debate. It is believed that the Stegosaur has two brains, one small brain in the skull and a larger brain located near the hip. Despite the brain in the skull being no larger than a walnut, scientists discovered that this brain was its primary brain that controlled the body, however the other brain only held nerves and controlled the hind limbs and tail, whilst possibly storing glycogen for powering muscles.