ENVIRONMENT
“In the year-round warm and wet conditions, plants can grow, flower and fruit nonstop”
Multistorey life in the rainforest The rainforest is a three-dimensional world, with multiple levels of wildlife up its towering trees Tropical rainforests are incredibly rich in wildlife. They cover about two per cent of Earth’s surface, yet they are home to around half of all the known species of flora and fauna. In the year-round warm and wet conditions, plants can grow, flower and fruit nonstop. That allows trees to quickly reach great heights. In a typical rainforest, the treetops overlap to form a continuous green layer called the canopy, about 45 metres (150 feet) above ground level. A few trees, called emergents, project well above this canopy – the tallest reaching over 80 metres (260 feet) high. The dense canopy of leaves blocks most sunlight from reaching the ground, where it is shady, damp and dank. For a visitor expecting to see a jungle full of colourful birds and monkeys, the rainforest floor is disappointing. A few small mammals do scurry about here, feeding on fruit that’s dropped from above, but they are mostly shy and secretive. Wild cats, like ocelots and jaguars, hunt them – mainly at night – but these are even more difficult to spot. Life on the forest floor is mostly small and hidden. Dead animals, broken branches and even whole trees from above are the food for myriad insects, worms and fungi. Along with bacteria, these decomposers play a vital role, quickly breaking down the detritus and releasing minerals and nutrients back into the soil to nourish new life in a perpetual cycle.
Meet the low life The lower storeys of the rainforest are leafy and shady, but jam-packed with hidden life
Epiphytic orchid 9,000 species of orchid live as epiphytes – growing on the platform of a branch, but extracting nothing from the tree like a parasite.
Swallow-tail kite This agile bird of prey soars above the canopy, searching for reptiles sunning on branches, then swoops in to snatch them.
Woolly monkey These noisy monkeys travel by day in large troops through the middle canopy, and rarely venture to the ground.
Northern tamandua This anteater uses its long, flexible snout to lick up insects in the lower forest layers.
Ocelot Ocelots are mediumsized cats. They hunt mainly on the forest floor, and spend the day well-hidden asleep in trees.
Scarlet ibis Jaguar
Scarlet ibises live in mangrove forests near the coast and feed on muddy shorelines.
Jaguars are shy, solitary and rarely seen. They hunt on the rainforest floor, and climb trees only to escape danger.
Brazilian tapir Tapirs are only active at night, foraging in swampy terrain. They hide in dense undergrowth by day.
Rainforest fungi Rainforest fungi produce a spreading network of fine threads to decompose dead wood. These ‘mushrooms’ are their spore-producing fruiting bodies.
Poison-arrow frog
Buttress root
Paca
Bright colours warn predators that these amphibians are deadly. Native Indians use the poison to tip their arrows.
Tree roots get little grip in thin rainforest soils, so many trees also have massive buttress roots to help prop them up.
A species of agouti (a rodent), the paca has strong enough jaws to open brazil nut fruit and release their seeds.
036 | How It Works
Coati
Anaconda
Coatis move in groups across the forest floor. They climb to mid-level in the trees, using their tails for balance.
This huge snake lives near rivers and swamps, hunting reptiles and small mammals, which it coils around to kill.
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