All forests on Earth have one very important – and obvious – feature: trees trees! Any ecosystem that is dominated by trees that are at least 6 feet tall is called a forest. Forest ecosystems are very important to humans because trees produce oxygen, which animals like us need to breathe.

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But there are many kinds of forests in the world: the tall redwood forests that cover part of California, the cold forests that grow near the tops of mountains, and even forests of mangrove trees that grow along the coast. But leafy tropical rainforests might be the most famous forests in the world.

More than half the world’s plant and animal species live in rainforests – that’s more than 5 million different species! And in the deep dark rainforest, there are many species that scientists haven’t even identified yet.


Because so many plants and animals live in there rainforest, it is one of the most crowded ecosystems on earth. With so many species packed together, plants and animals have figured out how to make space for themselves.

Some plants in the rainforest don’t even use the ground. Plants called epiphytes actually grow out of other plants, like off the branch of a tree! This way, they don’t have to compete with other plants for space on the forest floor.

Animals, too, use every nook and cranny of the rainforest. Poison dart frogs, for example, often lay their eggs in the tiny opening of these epiphytes. When it rains, the opening fills up with water, creating a perfect pool for the tadpoles to grow up in. In the crowded rainforest, no space is wasted!


Because so many different species live in a rainforest, it can be hard to stay alive. Some rainforest species rely on trickery to survive. When plants or animals pretend to be something they’re not, it’s called mimicry .

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Katydids, for example, are a delicious snack-size treat for birds and rodents. To stay safe, some katydids have evolved to look just like leafy green leaves! Because these insects mimic the plants they live on, it’s much harder for predators to find them.

A type of jungle cat called a margay also uses mimicry, but it uses mimicry to catch its food, rather than to avoid becoming food. Ocelots makes a high-pitched squeal that sounds like a monkey’s cry – but when other monkeys come to investigate what’s going on, the hungry margay snaps them up.


What is a rainforest without trees? Trees are one of the most important parts of a forest ecosystem – they provide food, shelter, and shade for other species, and produce the oxygen that we humans need to breathe.

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But we are cutting down millions of rainforest trees each year to make room for farms, get wood for our homes, and make paper to write on. In the last 40 years, we’ve cut down about 20 percent of the Amazon forest. This is called deforestation .

When we cut down trees, we lose more than just the trees. Birds that nest in trees lose their homes, and monkeys can’t find enough fruits and nuts to eat. More than 1000 different species of insects can live on a single tree in the rainforest, and when that tree disappears, so do they.

Since we humans are causing the problem of deforestation, we need to fix it if we want to save our rainforests. We need to use less paper and choose different building materials – like brick and concrete – instead of wood to build our homes. And people looking for land need to figure out how to farm or mine an area without destroying the rainforest.

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