The rainforest has enormous structural diversity, with layers of vegetation from the forest floor to the canopy 30m above providing a vast number of habitats. With the rainforest being stable over longer periods of time than temperate areas (there was no Ice Age here, nor any prolonged period of drought), the fauna has also had freedom to evolve, and to adapt to often very specialized local conditions. 

South America has been separated from the other continents for more than 100 million years – and was separate from North America until just a few million years ago – long enough to evolve its unique flora and fauna.

The best-known of all Amazon trees is the rubber tree (Hevea brasiliensis), known as seringuera in Brazil. Still a valuable export in Brazil today, a hundred years ago the rubber tree was the key to the Amazon’s initial exploitation. Also familiar is the Brazil nut tree (Bertholletia excelsa), which grows to 30m and takes over ten years to reach nut-bearing maturity; once this is reached, a single specimen can produce over 450kg of nuts every year.

The big Inga tree (Inga edulis) belongs to the mimosa family, and can grow to 36m. It has colourful patchy bark, large leaves and white hair-like flowers, similar to the mimosa, but its most distinctive feature is its bean pods, sometimes over half a metre long. The pods contain sweet white pulp and large seeds which some Indian groups use to treat dysentery, others for cleaning their teeth. The turtle-ladder vine (Leguminosae casalpinioideae), known as escada-de-jabuti in Brazil, is an unusual-looking liana which spirals high up from the earth to blossom in the canopy of primary forests. Often these lianas are older than the trees which they can be seen growing on.

There are a vast number of different spiky-rooted palm trees found throughout the forest. The main trunk starts some two or three metres off the ground, with its exposed roots protected from foraging animals by spikes; in this way the trunk is kept away from flood waters and the exposed roots are able to absorb nitrogen from the atmosphere rather than the soil. One example of this type of tree is the walking palm (Socratea exercisia), the wood of which is often used for parquet flooring. Tradition has it that it developed spikes to protect itself against the now extinct giant sloth, which used to push it over. The related stilt palm (Socratea exorrhiza) also grows abundantly in the Amazon, reaching heights of up to 15m. It has a thin trunk, very thorny stilt roots which grow like a tepee above the ground, and long thin leaves which are used by some indigenous groups as a treatment for hepatitis. The most utilized part, however, is the very hard bark which can be taken off and unwrapped in one piece for use as floor or wall slats.

Good areas for spotting wildlife in the Amazon are the richly diverse river banks and flood plains: here you are likely to see caimans, macaws and toucans, and you should catch sight, too, of one of a variety of hawks. With luck and observation you may spot a river dolphin, capybara or maybe even one of the jungle cats. In the jungle proper you’re more likely to find mammals such as the pecary (wild pig), tapir, tamandua tree sloth and, very rarely, the second-largest cat in the world, the powerful spotted jaguar. In general though, the open spaces of the Pantanal are better for spotting wildlife than the Amazon, where movement through the rainforest is limited to narrow trails and rivers.