All about dinosaurs!

written and designed by Jon
After two years of research about dinosaurs, I have decided to make a dinosaur homepage about dinosaurs. The page contains a lot of information about dinosaurs. I am usually called 'dinosaur' at school because I behave a bit like a dinosaur! But the facts are that no one really knows how dinosaurs behaved so far!

About 230 million years ago, some reptiles called dinosaurs evolved. One of the first dinosaurs was Plateosaurus. This herbivore is 6 metres long and 3 metres tall. It weighed a ton. One of the first carnivorous dinosaurs was Coelophysis. This slim dinosaur was 3 metres long, 1 metre tall and weighed 300 pounds. The first period of the the dinosaur age was the Triassic period. The dinosaur age is called the Mesozoic Era. The era means the age of reptiles or middle life.

The Jurassic period

In the Jurassic period, there were large meat eaters like Allosaurus which hunted plant eaters like Stegosaurus and Camptosaurus. Allosaurus also hunted huge dinosaurs like Diplodocus, Brachiosaurus, Camarasaurus, Apatosaurus, Barosaurus and many more. But Camptosaurus and Stegosaurus were Allosaurus favourite prey.

Sauropods in the Jurassic period


The next period of dinosaurs is called the Jurassic period. Sauropods like Diplodocus, Brachiosaurus, Camarasaurus, Seismosaurus and many other walked all over Laurasia and Gondwana land. In the Triassic period, all the present continents were joined together in a massive super continent called Pangaea. Meat eaters in the Jurassic period were far bigger than meat eaters in the Trissic period.One of them was called Allosaurus. Allosaurus is 11 metres long, 5 metres tall and weighed 2 tons. Smaller meat eater included Ceratosaurus. It is about half the size of Allosaurus. Ceratosaurus can run up to 50 kilometres per hour.

The defenceless dinosaur


Camptosaurus is 7 metres long and 4 metres tall. It's defenceless and it's the favourite meal of many meat eaters around.

Cretaceous dinosaurs

By the Cretaceous period, there were seasons. The horned dinosaur Triceratops is a plant eater. It's 9 metres long and 4 metres tall. It weighs 5 tons yet it can run as fast as a rhino! But even that was not the most powerful dinosaur. Tyrannosaurus rex is 12 metres long, 6 metres tall and it weighed 7 tons! But it can only run up to 30 kilometres per hour. Troodon was barely 1 tenth the size of T.rex But it was the most cleverest dinosaur ever! Troodon hunted in packs and it's main prey were lizards and baby dinosaurs.


One kind of Cretaceous plant eaters was quite interesting. Those dinosaurs were called Hadrosaurs. Edmontosaurus was a Hadrosaur which lived at the end of the Cretaceous period. Edmontosaurus was probably the favourite prey of Tyrannosaurus rex. There were still some Sauropods in the Cretaceous period. Alamosaurus livd at the same place and time as Tyrannosaurus rex and was tree times larger than Tyrannosaurus rex.



There was another group of interesting dinosaurs in the Cretaceous period. They were called Pachycephalosaurs. The biggest Pachycephalosaur was Pachycephalosaurus. This plant eater can grow up to 8 metres long. Pachycephalosaurs had a thick bone on top of their heads. These are used for mating. The fight like bison.


Another kind of plant eating dinosaur which live in the Cretaceous period were Ankylosaurs. Although Ankylosaurs evolve in the Jurassic period, there were more Ankylosaurs in the Cretaceous period than in the Jurassic period. Ankylosaurus was about the size of a army tank and it lived in Tyrannosaurus rex's world.


One ancestor of Tyrannosaurus rex was Albertosaurus. This meat eater is a little bigger than half the size of a Tyrannosaurus rex. In the late Cretaceous period, Asia and North America was joined together. Tyrannosaurus rex roamed North America and Tarbosaurus, a relative of Tyrannosaurus rex roamed Asia.


Tarbosaurus was a Tyrannosaur and Velociraptor was a Dromaeosaur. These dinosaurs had large second-toe claws that can rip through meat. Velociraptor is 2 metres long and a metre tall. They can run up to 50 kilometres per hour and can leap 2 metres high! The largest Dromaeosaur yet discovered was called Utahraptor. The Dromaeosaur is found in Utah and this Dromaeosaur is 6 metres long, 3metres tall but it probably weighed only half a ton! It hunted in packs and it can kill a large plant eater like Iguanodon which is 4 times larger than Utahraptor! Iguanodon is one of the first dinosaurs to be found. It was found by Dr. Mantell.

Fast dinosaurs

In the Cretaceous period, some super fast Theropods evoved. The most famous is Gallimimus, which lived in Mongolia 80 million years ago and it can run 70 kilometres per hour! It's main predator is Tarbosaurus. Gallimimus is 6 metres long and 2 metres tall. It runs on two thin hind legs and it weighs only 500 pounds! Tarbosaurus can only run 30 kilometres per hour and Gallimimus can run up to 70 kilometres per hour.

Early-found dinosaurs

William Buckland found the first dinosaur to be named. It was called Megalosaurus and it's name means Great Lizard. It's main prey is probably Iguanodon. When Dr.Mantell found Iguanodon, he thought that one of it's thumb claws was a horn! Iguanodon was 12 metres long, 5 metres tall and it weighes 3 tons. Megalosaurus was 9 metres long, 4 metres tall and it weighes a ton. They lived in Europe around 100 million years ago! Dinosaurs evolved 230 million years ago and went extinct 65 million years ago. Tyrannosaurus evolved 70 million years ago. Homo Sapiens, modern people only evoved 2 million years ago!

Fast animals compared

The fastest dinosaur is Dromiceiomimus. It can run around 80 kilometres per hour, about the speed of a ostrich. Cheetahs can run faster, about 110 kilometres per hour but it can't run for more than 30 seconds. The fastest humans can run only 35 kilometres per hour. Ornithomimus, a relative of Dromiceiomimus can also run 80 kilometres per hour. It speed is it's only defence when it meets the king of the dinosaurs, Tyrannosaurus. It's relative, Daspletosaurus is smaller than Tyrannosaurus rex but it can run faster.

Huge dinosaurs

You'll probably think that Tyrannosaurus is the largest meat eating dinosaur, but it isn't. Recent discoveries in Argentina showed a meat eating dinosaur a bit bigger than Tyrannosaurus and it's name is Giganotosaurus. It is 13.5 metres long, 6.5 metres tall and it weighes probably 8 tons. Althrough it was big, there was a enormous plant eating dinosaur which lived in it's area. It's name was Argentinosaurus. It was a massive 40 metres long, 12 metres tall and maybe it weighed up to 150 tons! Giganotosaurus must had to hunt in packs to kill this massive beast. This massive beast belong to a group of late Cretaceous period Sauropods called the Titanosaurs which had armour. The most famous Titanosaur is Titanosaurus which was 20 metres long, 10 metres long and it might weigh up to 10 to 20 tons. It lived in Europe 80 million years ago. Actually 80 million years in Europe was a chain of islands. Saltasaurus was a Sauropod which lived in South America. It was a smaller Sauropod about 12 metres long, 8 metres tall and it weighed around 8 to 10 tons. It's main predator is Carcharodontosaurus, which is the second largest meat eating dinosaur after Giganotosaurus and Carcharodontosaurus means Shark Tooth Lizard. The only Sauropod in Tyrannosaurus world is called Alamosaurus. Alamosaurus is small for a Sauropod but it is three time bigger than Tyrannosaurus. Tyrannosaurus had long, strong legs but Tyrannosaurus had small, weak arms. Scientists think that large arms will had slowed a Tyrannosaurus down while bitting a victim. if Tyrannosaurus can only move as fast as a elephant, it might as well be a scavenger, not a killer. It can probably scare all the other smaller meat eating dinosaurs away, but it's incredibly strong jaws is evidence that it was a killer, not a scavenger. Troodon, a much smaller meat eating dinosaur, could have been a scavenger when it was alone. But if it was in a pack, it could have killed small dinosaurs or baby dinosaurs. Troodon had large hand claws and small teeth but Tyrannosaurus had large teeth and small hand claws! That means that Troodon can hold it's food but Tyrannosaurus can't. Allosaurus can hold it's prey because it's arms are just long enough.

Jurassic giants

Sauropods have different skulls. Diplodocus' skull is low and long but Camarasaurus' skull is more like a circular shape, not like Diplodocus' skull, which is rectangular. Diplodocus is probably light for a Sauropod because it has hollow bones. Half of Diplodocus' body is made out of it's tail. Seismosaurus, which is 50 metres long is probably the longest dinosaur. Ultrasauros, which is 15 metres tall is probably the tallest dinosaur. The heaviest dinosaur is probably Argentinosaurus, which probably weighed 150 tons!

Caring dinosaurs

Maisaura isn't very special as it looks, but there is evidence to prove that female Maisauras cared for their babies the most! Maisaura was 7 metres long, 3 metres tall and it weighs 2 tons. The largest carnivore in Maisaura's world is Daspletosaurus which is 9 metres long, 4 metres tall and it weighed 2 tons.

Dinosaur defences

Ankylosaurus weighes as much as an elephant and it's legs are almost the same thickness. So Ankylosaurus can probably run as fast as a elephant. Maybe it can run even faster because it has a long tail to keep it from falling down. At the end of it's tail is a club which weighs around 30 to 50 pounds. But when Ankylosaurus swings it's tail club, the force is 2 to 3 tons! That's the weight of a van! That's enough to break a Tyrannosaurus bone and strong enough to send a Troodon or a Dromaeosaurus flying! Triceratops' horns is enough to crash through wood and break the ribs of a Tyrannosaurus! Struthiomimus is as fast as an ostrich and half of Struthiomimus' top speed is fast enough to match a Olmpic sprinter! A group of Edmontosaurus using their warning signal sounds is as loud as a hundred motor cycles! One direct smash from Pachycephalosaurus' thick bone head can crack a piece of wood 5 centimetres thick! One smack from Alamosaurus' tail can send a bookshelf flying!

Flying reptiles

There were flying reptiles which lived at the time of the dinosaurs. They were called the Pterosaurs. The largest Pterosaur is called Quetzalcoatlus. It is 12 metres wide. It probably ate fish. The second largest known Pterosaur is called Pteranodon. It is 9 metres wide.

Sea reptiles

There were also giant sea monsters at the time of the dinosaurs. One of them is Elasmosaurus. Half of it;s body is it's tail. Another kind of sea monster is Icthyosaurus. It looks like a dolphin and it gives birth to live young.

A dinosaur which liked fish

Talking about the sea, some dinosaurs ate fish. One of them is Baryonyx. It is 9 metres long, 4 metres tall and it weighed around a ton. It's head looks like a crocodile's head. So Baryonyx could have ate fish. It had a huge claw on it's second finger. It was the size of a banana and Baryonyx might have used this claw to catch fish!


In the Jurassic period, Stegosaurs were very common. The largest Stegosaur is Stegosaurus. It is 9 metres long, 4 metres tall and it probably weighed 2 tons. But it was probably stupid for a dinosaur! For such a big animal, a brain the size of a rat will not make this dinosaur a smart dinosaur! Stegosaurus was just one Stegosaur. It had a Asian relative called Tuojiangosaurus. It is a little smaller than Stegosaurus. Most Stegosaurs became extinct at the end of the Jurassic period but a few still survived until the end of the Cretaceous period! Stegosaurs and Sauropods are probably the slowest dinosaurs because they have short legs and they seemed to be quite slow because they were big.

The end of the dinosaurs

Then, something 65 million years ago happened. Perhaps an asteroid struck Yucatan Peninsula in Mexico. It left a huge crater 125 kilometers wide! Scientists are not sure if that had killed the dinosaurs. But mostly, it was something to do with the climate change. The crater is called the Chixulub crater. The asteroid was 10 kilometers wide but the crater it left was 125 kilometers wide! It traveled 30,000 kilometers per hour when it hit earth! The asteroid sent dust flying into the atmosphere and without sunlight, plants cannot grow. The meat eaters ate the plant eaters but the plant eaters cannot reproduce because they were already dead so without anymore plant eaters to eat, some meat eaters ate other meat eaters but when they went out of meat eaters to eat, they died too! And, if they died, they can't reproduce new dinosaurs! And if they can't reproduce, there are no more dinosaurs, they are extinct! And if they are extinct, mammals takeover! Why? Because the Pterosaurs and the giant sea monsters also became extinct! There were tiny mammals like Megazostrodon which lived at the time of the dinosaurs, but they only became larger because the dinosaurs became extinct. Althrough dinosaurs were extinct, when they rule the earth, they are very facinating!

Here are some amazing pictures of dinosaurs below and they are nonfiction!


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