Category Science

The first people we think of as humans appeared in Africa. About two million years ago, Homo habilis (handy man) appeared. Then, more than one million years ago, Homo erectus (upright man) appeared, but they weren’t modern humans.

Did they have any tools?

Homo habilis was the first tool-user. This is why he is called ‘handy man’. He made simple tools, such as choppers, from pebbles. The tools made by Homo erectus were better. He shaped stones into hand axes, and he was the first to use fire.

What did they eat?

Homo habilis and Homo erectus ate meat and plants. Meat probably came from dead animals which they found. They may have hunted for some small animals. Plants gave them berries and leaves. They used stone tools to cut and scrape their food.

Amazing! Homo erectus had fire. Fire provided warmth, gave heat for cooking, and offered protection from predators.

Is it true? Homo erectus was a wanderer.

Yes. More than one million years ago, Homo erectus began to move out of Africa, travelling to Europe and Asia.

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.

Amazing! Woolly mammoths were big elephants with extra-long tusks up to 3 metres long. Their bodies were covered in fur.

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.

Is it true? The elephant is the largest land mammal ever to have lived.

No. Indricotherium was the largest land mammal. It was almost 8 metres tall and as heavy as four elephants.

Picture Credit : Google

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.

Amazing! 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.

About 300 million years ago, some amphibians changed into reptiles. They could live on land all the time. Reptiles have backbones and scaly skin, and most lay eggs. Many reptiles, such as crocodiles, spend lots of time in the water, but they can’t breathe underwater. They use the Sun to keep their bodies warm.

Is it true? Some early reptiles had sails, on their backs.

Yes. Dimetrodon had a skin ‘sail’ on its back. It soaked up the Sun’s heat, and controlled the animal’s body temperature.

Amazing! A small animal found in Scotland, in rocks that are 350 million years old, might be one of the first reptiles. But some scientists say it was an amphibian.

What did reptiles eat?

The first reptiles, such as Hylonomus, were small lizard-like animals that ate tiny creatures. Reptiles learned how to run quickly so they could catch fast-moving insects. As reptiles became larger, they caught and ate bigger prey, including other reptiles. Some reptiles only ate plants.

Which reptiles had fur?

Some prehistoric reptiles grew fur on their bodies to keep themselves warm. These were the cynodonts. They lived about 245 million years ago. Over time they changed into a completely new group of animals, called mammals.

Picture Credit : Google