Birds are animals with backbones, they lay eggs, can make their own body heat, and have wings. They are also the only animals with feathers. Not all birds can fly. The first birds lived at the same time as the dinosaurs.
Is it true ?
Ostrich eggs are the biggest eggs ever laid by a bird.
No. The extinct bird Aepyornis laid the biggest eggs of all time. Each one was about the size of 150 hen’s eggs.
Where do birds come from?
Birds evolved from small, meat-eating dinosaurs. Fossils show that some of these dinosaurs had feathers. They are called ‘dinobirds’. The first ‘dinobirds’ probably could not fly.
Today’s hoatzin bird, which lives in South America, has claws on its wings when young – just like Archaeopteryx, its prehistoric ancestor, did.
Which was the first true bird?
The first true bird – a bird that could fly – appeared about 150 million years ago. It is known as Archaeopteryx, which means ‘ancient wing’. It had claws on its wings.
What are mammals?
Mammals have backbones, their bodies are covered in hair or bristles, they make their own body heat, and they feed their young on milk. They have larger brains than most other animals.
When did the first mammals appear?
The first mammals appeared on Earth about 220 million years ago. They lived at the same time as the dinosaurs. Mammals survived after the dinosaurs died out, and then they became the ruling animals on Earth. There are about 4,200 different kinds of mammals alive today.
Did mammals only live on land?
Mammals came to live in all of Earth’s habitats. Many lived on land, but some, such as bats, were able to glide through the air on wings of skin. Other mammals swam in the sea, such as whales, dolphins and seals.
Woolly mammoths were big elephants with extra-long tusks up to 3 metres long. Their bodies were covered in fur.
Is it true?
The elephant is the largest land mammal ever to have lived.
- Indricotherium was the largest land mammal. It was almost 8 metres tall and as heavy as four elephants.