About Amazonia
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Contents

Introduction

Living in Amaz⌠nia

Early Explorers

Scientists & Adventurers

Exploration Today

Development

The Rubber Boom

Environment

Natural History

Natural History

Rainforests developed millions of years ago, when many of the world’s continents were connected together into two giant super-continents called Laurasia (comprised of North America, Europe and Asia) and Gondwanaland (comprised of South America, Africa, India, Australia, and Antarctica).

Because continents were joined together, they shared similar wildlife and forests. This is the reason why the big cats in Africa, such as the leopard and the lion, have cousins which live in South America such as the jaguar and puma. Boa constrictor snakes are related to pythons, llamas are related to camels, and the South American tapir is related to the African rhinoceros and has another close relative which lives in Malaysia. There were once even native South American horses, but these became extinct as a result of hunting by the early Indians – until horses were reintroduced into the Americas 500 years ago by the Spanish. Because of their common origins, the rainforests of South America, Africa, Australia, and parts of Asia, still share many similarities today [footnote 1].

Because continents move very slightly each year – the continents which made up Gondwanaland slowly drifted apart [footnote 2]. It took them millions of years to drift to the point where we recognise them today – but, if you look at a map, you can see how Africa and South America once fitted together like two pieces in a gigantic jig-saw. As the continents moved apart, conditions for the plants and animals changed so that the plants and animals in South America adapted differently from the plants and animals in Africa and Asia.

Even within South America, territories were often isolated from one another by high mountain ridges, or by wide inland oceans and rivers. These forced plants and animals in some areas to develop differently from the plants and animals living in other regions. Later, when the inland ocean which flooded most of the Amazon basin dried up, it connected together many of these once-isolated territories – and resulted in a huge rainforest containing an enormous variety animals and plants. There are far more species of plants and animals living in Amaz⌠nia than there are anywhere else on earth. There are about 2,500 species of trees, 2,000 species of fish, 2,200 species of birds, and about a million species of insects. Because Amaz⌠nia is located on the equator, within the tropics, the weather is hot and wet with almost daily downpours of rain. Plants love these conditions, so the rainforests have grown lush and rich even though the soil that they’re growing on is poor in nutrients. Having so many species together in one place is known as biodiversity.

Humans are very recent arrivals in Amaz⌠nia. The first people arrived about 15,000 years ago. They were Indians who had originally migrated across the Bering Strait from Asia and Siberia into North America, then gradually moved downwards into South America. These first peoples were nomadic hunters who hunted large animals such as buffalo, deer, mammoths, horses, and the now-extinct giant ground sloth. Unfortunately, as a result of hunting, many of these animals either became extinct or became increasingly difficult to find – forcing people to find new ways to live. People living near the Andes took to farming – raising animals and crops to feed their families – while people living in the rainforests learnt how to hunt smaller animals, fish, plant gardens, and gather produce from the surrounding forests.

Footnote 1
New Zealand was also part of Gondwanaland, but the reason that our country developed differently is because New Zealand broke away from the super-continent before mammals had a chance to evolve. That’s why our only native mammals are bats whose ability to fly may have helped them get here when the gap between New Zealand and the rest of the continents was still relatively small. Our isolation from the other continents is also why our own rainforests are so special, because they show us how other forests might have looked 65 million years ago.

Footnote 2
The movement of continents is known as continental drift and occurs because the surface of the earth is grouped into several large areas known as tectonic plates. These plates move slowly across the earth’s surface, causing earthquakes as they rub against each other. In general, the plates only move a few centimetres each year – but over a long period of time this is enough to open up gaps creating new oceans, or new mountain ranges where two plates are crashing into each other.