Types of Dinosaurs
What do you already know about the different types of dinosaurs that used to live?
The Mesozoic Era lasted for an amazing 186 million years! Humans have only been on Earth for 300,000 years! The time that dinosaurs ruled the Earth was so long it is impossible to imagine. Over time the Earth and the type of dinosaurs that lived changed…dramatically!
All dinosaurs were reptiles, but they weren’t all the same, at all! They were all vertebrates with a skeleton inside their body. Some were big, some were small. Some had thick scaly skin, like reptiles do now, while some also had feathers. Some were carnivores but most actually were herbivores. Some were terrifying but actually lots were gentle. Lots lived in groups but some preferred to be on their own. All dinosaurs hatched out of eggs. While some were well looked after, others had to look after themselves as soon as they hatched.
Just like the animals we have living on Earth today, because of how different the dinosaurs were, we can put them into groups. This helps us to understand what the different dinosaurs were like.
The two main groups are based on the way dinosaurs hip bones were shaped. Your hips are where your legs join the rest of your body. Saurischians were lizard hipped dinosaurs and included theropods and sauropods. Ornithischians were bird hipped dinosaurs, including ceratopsians, ornithopods, stegosaurs and ankylosaurs. Let’s find out what those long names mean.
Theropods
The name theropod means beast foot.
Dinosaurs that were theropods were generally very scary and fierce! Most were carnivores and attacked other creatures that lived around them like insects, lizards and other dinosaurs. Some hunted on their own and some hunted in packs. Some theropod dinosaurs were actually omnivores or even herbivores though!
The theropod dinosaurs walked on their back two legs. Their front legs were much shorter. They had long flexible necks and tails. They had sharp curved claws for killing and had razor sharp dagger like teeth which they used to eat their prey. Some were as big as a minibus and some were as small as a chicken.
Theropods first appeared in the late Triassic, and then throughout the Jurassic and Cretaceous Periods – pretty much the whole way through the Mesozoic Era.
Theropods in the Triassic Period were really quite small. An example of a Triassic theropod is Coelophysis. Dinosaurs in the Jurassic Period that were theropods were Allosaurus and Compsognathus. Finally theropod dinosaurs in the Cretaceous Period were Tyrannosaurus Rex, Albertosaurus, Velociraptor, Spinosaurus and Giganotosaurus.
Albertosaurus lived a few million years before the bigger T Rex.
Spinosaurus was the largest theropod dinosaur and largest carnivore to ever walk the Earth!
Sauropods
The name Sauropods means lizard foot.
Dinosaurs that were sauropods were massive creatures and the biggest animals to ever walk on Earth. Their fossils have been discovered in every continent in the world, meaning they lived everywhere.Â
The sauropod dinosaurs had really, really long necks and super long, whip like tails. They walked on all fours and their legs looked a bit like an elephants. Their heads were quite small compared to the rest of its body and were a bit bigger than a horses head. To protect themselves from predators they lived in herds and would use their strong long tail to whack the predators and keep them away. Younger sauropods walked in the middle of herds so the adults could protect them.
They were all herbivores, which means they ate plants. They had to travel every day because they were so greedy and they ate all the food around them. They had to eat stones to help them grind down their food in their stomachs.
Sauropods first appeared at the end of the Triassic Period. They lived throughout the whole of the Jurassic and this is when there were the most of them, however some sauropods did live during the Cretaceous Period too.Â
Plateosaurus was an early type of sauropod living in the late Triassic period. Sauropods during the Jurassic Period included Diplodocus and Brachiosaurus in massive numbers as well as Apatosaurus, Camarasaurus, Brontosaurus and Supersaurus. In the Cretaceous Period Titanosaurus dominated.
Probably the most well known sauropod, but not the biggest!
Ceratopsians
The name ceratopsians means horned face.
Dinosaurs that were ceratopsians were very heavy dinosaurs and were very slow moving. But like many dinosaurs that ate plants they had to travel long distances to find food. They chewed their food with their powerful jaws, so it was much easier to digest (unlike the sauropods)
The Ceratopsians were quite large dinosaurs, but not compared to some! They walked on all four legs, which looked a bit like elephant legs do now. The ceratopsians couldn’t run very fast so they found it very difficult to escape from predators. But they did have ways to protect themselves from them. They had hard bony frills to protect their necks and some had horns, which they used to defend themselves. Like many herbivores they also lived in herds for protection from predators like T-Rex.
Ceratopsians lived in Cretaceous period at the end of the Mesozoic era. Triceratops was a ceratopsian, as well as Centrosaurus, Styracosaurus and Protoceratops.
Less well known than Triceratops but you can see the similarities!Â
A ceratopsians frill was not just for protection. It is believed it helped cool the dinosaur down and helped the dinosaurs to show off and attract mates.
Ornithopods
The name ornithopods means bird foot.
Ornithopods varied in size. They could walk on both two and four legs and had hips that were more like birds than other dinosaurs. They had three toes and spikes for thumbs which they used for finding food or to defend themselves. They had beaks and molar like teeth they used for grinding up their food.
Ornithopods lived in groups and were herbivores.
They lived in the late Triassic and the whole of the Jurassic and Cretaceous periods. Ornithopods included Camptosaurus, Hypsilophodon, Parasaurolophus and Iguanodon.
The most well known of the ornithopods.
Camptosaurus didn't have a big cone like spike like Iguanodon. It had a much smaller thumb.
Stegosaurs
The name stegosaurs means roof lizard.
Stegosaurs were armoured dinosaurs with a protective hard covering on part of their body. They also had triangular bony plates along their curved backs and and spikes on their tail. They walked on all fours, but their front legs were a bit shorter than the back ones.Â
Stegosaurs lived in herds for protection and were gentle herbivores, unless attacked or threatened, when they could use the terrifying spikes on their tail as an effective weapon against predators.
They lived in the late Jurassic and early Cretaceous Period. Dinosaurs that were stegosaurs included Stegosaurus, Kentrosaurus and Tuojiangosaurus.
Baby stegosaurs probably had plates at birth but they would have been smaller and softer when born.
You can see where the armoured part of their bodies stopped.
Ankylosaurs
The name ankylosaurs means fused lizard.
Ankylosaurs were armoured dinosaurs. They had a thick bony armoured shell that was made up of interlocking plates, completely covering its back and most of its sides. They had a solid club on the end of its tail they could use for protection. They were very solid dinosaurs, and walked love to the ground on four short thick legs.
Ankylosaurs first appeared in the Jurassic and lived throughout the Cretaceous period. Ankylosaurus was one of these dinosaurs as well as Euoplocephalus.
You can clearly see what part of their body the amour protects.
Despite such good amour ankylosaurs did have predators that would still try and attack them.
What we've learnt...
All dinosaurs were reptiles born from eggs. Some dinosaurs were carnivores but most were gentle herbivores.
There are two main groups of dinosaurs based on how their hip bones were shaped. Saurischians were lizard hipped dinosaurs and Ornithischians were bird hipped dinosaurs.
Theropods were (mainly) terrifying meat eating dinosaurs.
Some sauropods were the biggest creatures to ever walk on Earth.
Ceratopsians, stegosaurs and ankylosaurs all had types of body armour to protect themselves.
Test your knowledge...
Types of Dinosaurs Quiz
If you click the correct answer the box will turn green. If its the wrong answer it will turn red and then show you what the correct answer was. Make sure you read or listen to the questions carefully!
#1. What type of dinosaurs were the most armoured?
#2. Which group of dinosaurs ate other dinosaurs?
#3. Were dinosaurs reptiles?
#4. Which group of dinosaurs has a name meaning horned face?
#5. Did all dinosaurs hatch from eggs?
Results
I really hope you have enjoyed learning all about the different types of dinosaurs, with me Flash!
Question Time...
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The photos on this page are mainly of dinosaur models. They are used to give you a idea of what the dinosaurs would have looked like, but I can’t guarantee they are 100% accurate!
Creative Commons Images, used with thanks…
Iguanodon by Marcin Polak – CC BY 2.0
Camptosaurus by Todd Van Hoosear – CC BY-SA 2.0
Kentrosaurus by Elekes Andor – CC BY-SA 4.0
Ankylosaurus by Brittney Le Blanc – CC BY-SA 2.0
Other photos and illustrations on this page are Whizzbots, Shutterstock or Public Domain Images.