Layers of the rainforest: climb down four tropical rainforests
What are the layers of the rainforest?
In short, a tropical rainforest has four layers. From the sky down, they are the emergent layer, the canopy, the understory and then the forest floor. Each one also has its own light, heat, humidity and animals. Most rainforests have rivers running through them as well, so the climb above ends with a fifth stop: the river. Tap a layer below, and you jump straight to its animals.
I built this climb because a flat diagram never made sense to me as a student. For example, a drawing shows four neat stripes. However, a real rainforest is a vertical world. A harpy eagle and a dart frog can live 60 m apart and still never meet. So scroll down slowly, and the light drains away just as it does in the forest.
Rainforest animals, layer by layer
Here are all 63 animals from the climb, so you can see who lives where. Each one sits in the layer where it spends most of its time, although many move between layers. As a result, the heights on the cards are typical ranges rather than fixed addresses. Pick a rainforest to filter the cards, then tap any card for my full guide.
The emergent layer (40 to 80 m, depending on the forest)
A few giant trees punch through the roof of the forest. Their crowns then spread out in full sun. Up here the wind is strongest and the midday air is hottest. Meanwhile, the humidity is the lowest in the forest. Consequently, most residents are fliers and powerful climbers. For example, the harpy eagle perches on emergent branches, then drops into the canopy to snatch sloths and monkeys.
The tallest tree ever measured in the Amazon is a red angelim, 88.5 m tall (Gorgens et al., 2019). Borneo, however, goes higher still. There, a yellow meranti called Menara reached 100.8 m (Shenkin et al., 2019).
The canopy (about 20 to 45 m)
Above all, the canopy is the busiest layer. Up here, branches and leaves join into one continuous roof. This roof catches most of the sunlight and rain, so it also holds most of the fruit, flowers and new leaves. Naturally, the animals follow the food. As a result, toucans, parrots, monkeys and sloths spend their lives up here, and many never touch the ground. Orchids, mosses and bromeliads grow on the branches too. In fact, some bromeliads hold enough rainwater for frogs to raise their tadpoles inside.
The understory (about 2 to 25 m)
Below the canopy, the air turns still, warm and sticky. However, only a few percent of the sunlight gets through. So understory plants grow big, dark leaves to catch whatever filters down. Young trees wait here for years until a neighbour falls and opens a gap. Meanwhile, hunters such as the boa constrictor and the clouded leopard work the half-light. The blue morpho, on the other hand, flashes past like a switched-on lamp.
The forest floor (0 to 2 m)
Only about 2% of the sunlight reaches the ground, so the floor stays dim even at noon. Meanwhile, fallen leaves rot within weeks in the heat and damp. Fungi, termites and bacteria then recycle the nutrients almost at once. As a result, rainforest soil usually stays thin and poor. The biggest animals also live down here. Many of them, such as tapirs, cassowaries and forest elephants, swallow fruit whole. Later they drop the seeds far away, which is why ecologists call them gardeners of the forest.
The river below (the bonus fifth stop)
Eventually, rainforest rivers carry the rain back to the sea. For instance, the Amazon alone pours about a fifth of all the river water that reaches the oceans. In the wet season, it also floods the forest for months. Meanwhile, the Congo River splits chimpanzees from bonobos in Central Africa. Neither ape can swim across, so chimpanzees stay north while bonobos stay south. That is also why the climb above ends underwater.
Four rainforests, four different climbs
Tropical rainforests grow near the Equator, because it stays hot and wet there all year. They usually receive at least 1.75 to 2 m of rain a year, although many places get far more. Even so, they are not all the same height. So use the tabs at the top of the climb to compare them.
The largest tropical rainforest on Earth spreads over more countries than any other. Look for the harpy eagle and the scarlet macaw, as well as the toco toucan. Its cousin, the blue and yellow macaw, also grows to about 90 cm long.
Second only to the Amazon in size, it is home to gorillas, chimpanzees and bonobos too. It also shelters okapis and forest elephants.
These forests grow the tallest trees of the four, so the climb starts 80 m up. They also hold orangutans, tigers, the Sumatran rhino and the proboscis monkey.
The trees here are shorter than in the other three. Even so, Guinness World Records lists it as the oldest tropical rainforest on Earth.
Central America deserves a mention too, even though it has no tab yet. For example, its rainforests are home to the keel billed toucan, the national bird of Belize. Its bill also shows a rainbow of green, orange and red. So if you want to see rainforest birds and monkeys yourself, start with my guides to the animals of Costa Rica and the monkeys of Costa Rica.
Who eats whom? Rainforest food chains
Every card in the climb also lists what the animal eats and what eats it. Then, when you tap a predator’s name, you jump straight to it. For example, here are four simple chains, one from each forest. Notice how often the top predator hunts in a different layer than its prey.
Why tropical rainforests matter to the whole planet
Tropical rainforests cover only a small slice of Earth’s land. However, they hold somewhere between 40% and 75% of all species. For example, a single hectare can contain tens of thousands of insect species. Similarly, about two-thirds of all flowering plants grow in rainforests. In other words, these forests are the jewels of life on Earth, and most of their species still have no name.
They also play an important role in the climate. Rainforest trees pull carbon dioxide out of the atmosphere and lock it up in wood and soil. As a result, they work as massive carbon sinks. Their leaves also release huge amounts of water vapour, which drives rainfall far beyond the forest. In fact, the Amazon partly makes its own rain. Dense canopies protect rivers from erosion, too. Finally, around a quarter of modern medicines come from compounds first found in rainforest plants.
Many people still call the Amazon “the lungs of the Earth”.
A mature rainforest uses up almost all the oxygen it makes, because its animals, fungi and microbes breathe it. Roughly half of the oxygen in the air comes from ocean plankton instead. So rainforests matter for carbon, rain and species, rather than for our oxygen.
What is destroying the rainforests?
Deforestation comes mostly from farms. In particular, forests are cleared for cattle, soy, palm oil, pulpwood and other crops. Often this happens by slash and burn, when trees are cut and the rest is set alight. Fire has also become a growing threat on its own. In 2025 the tropics lost 4.3 million hectares of primary forest, more than 11 football fields every minute. That was 36% less than in 2024, a record year for fires. Even so, losses stayed higher than a decade ago (Goldman et al., 2026).
When large areas of habitat disappear, the species that depend on them go too. That is why so many animals on the Sumatra tab, from the tiger to the rhino, are Critically Endangered. I also explain the bigger picture in what habitat destruction is and how climate change threatens animals.
How you can help protect rainforests
Test yourself: three quick questions
Think of your answer, then tap to check. The full five-question quiz also waits at the bottom of the climb.
Which layer of the rainforest holds the most animals?
The canopy, because it catches most of the sunlight and so makes most of the fruit.
Why is rainforest soil so poor, when the forest is so rich?
Because nutrients never sit still. Leaves rot within weeks, while roots and fungi grab the nutrients as soon as they are released.
Which ape can’t cross the Congo River, chimpanzee or bonobo?
Neither, so chimpanzees stay north of the river while bonobos stay south of it.
From the field
The rainforest I know best is Springbrook, close to my home in South East Queensland. It belongs to the Gondwana Rainforests of Australia, and it is subtropical rather than tropical. Still, the layers feel the same when you walk through them. In fact, on one hike there in 2025, I saw five red-bellied black snakes. Two of them were mating in the open, too, right beside the track.
Besides, many animals in this climb are ones I have worked with up close. For example, I worked in the reptile and amphibian house of a zoo in North America. There I cared for poison dart frogs, boas, anacondas and reticulated pythons. So I know how small a dart frog really is, and how heavy a big python feels. Later, in April 2024, I saw my first hornbill in Langkawi, Malaysia. An Oriental pied hornbill simply landed on a beach sign right beside me. As a child, I also lived in Villahermosa, Tabasco, facing a river where crocodiles were part of daily life. So the river at the bottom of this climb felt essential to me.
Cesar Medina, conservation biologist
How the climb works
Each tab uses typical heights for that rainforest. However, the layers are stretched so every animal gets room on screen. As a result, the forest floor takes up more scrolling than its real 2 m. The readings for sunlight, humidity and temperature are typical midday values. So they show the trend from top to bottom, rather than one exact spot. Animals are also drawn at a rough true scale, so an elephant really does dwarf a dart frog. Finally, turn on the jungle sounds and make it rain, because the climb changes as you go down.
More wildlife interactives
- Deep sea dive Scroll 10,935 m to the Mariana Trench, then meet 61 ocean animals.
- The Great Animal Speed Race Race a jaguar and a cheetah against Usain Bolt, then spin the speed dial.
- Animal size comparison Line up a gorilla, an elephant and a person, so you see their true scale.
- Animal migration maps Follow the great journeys while the map shows where herds are today.
- Rainforest animals guide Meet more rainforest species, as well as their photos and facts.
- Rainforest birds Toucans, hornbills and macaws, plus the other stars of the canopy too.
Frequently asked questions
How many layers does a rainforest have?
In short, a tropical rainforest has four layers: the emergent layer, the canopy, the understory and the forest floor. Some guides also add rivers and streams as a separate habitat, just as the climb above does.
Which layer of the rainforest has the most animals?
The canopy, because it catches most of the sunlight. As a result, it produces most of the fruit, flowers and leaves.
How much sunlight reaches the rainforest floor?
Only about 2%, because the canopy and understory absorb the rest. So the forest floor stays dim, even at midday.
What is the largest tropical rainforest?
The Amazon is the largest, since it spreads across nine countries in South America. After that comes the Congo Basin rainforest in Central Africa.
Which is the oldest rainforest in the world?
Guinness World Records lists the Daintree Rainforest in Queensland, Australia, as the oldest tropical rainforest. In fact, it puts its age at 180 million years.
Is the Amazon the lungs of the Earth?
Not really, because a mature rainforest uses almost all the oxygen it produces. Instead, it matters because it stores carbon, makes rain and shelters a huge share of Earth’s species.
What is the tallest tree in a rainforest?
So far, the record is Menara, a yellow meranti in Borneo measured at 100.8 m in 2019. In the Amazon, by comparison, the record is a red angelim of 88.5 m.
