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form such a dense, unbroken tangle of vegetation that landing and travelling through the forest on foot seems impossible. From the boat, it looks like the jungle of myths and legends: a place of mystery, extreme discomfort and danger. Yet things look much different deeper in the rainforest. In the heart of a healthy rainforest there is no tangle of jungle vegetation, because almost no direct sunlight reaches the ground to stimulate growth. Instead there are just the trunks of massive trees, soaring almost branchless 165 feet (50 m) up to the forest canopy. Here they finally spread out, parasol-like, to catch the sun’s rays. Animals are all around, in the uppermost branches and in the leaf litter under- foot, but they are mostly silent and difficult to spot. The atmosphere is cathedral-like, with the tree trunks resembling mighty columns. It A biome is a very large ecological area, with plants and animals that are adapted to the environmental conditions there. Biomes are usually defined by physical characteristics—such as climate, geology, or vegetation—rather than by the animals that live there. For example, deserts, rainforests, and grasslands are all examples of biomes. Plants and animals within the biome have all evolved special adaptations that make it possible for them to live in that area. A biome is not quite the same as an ecosystem, although they function in a similar way. An ecosystem is formed by the interaction of living organ- isms within their environment. Many different ecosystems can be found within a single biome. Components of most ecosystems include water, air, sunlight, soil, plants, microorganisms, insects, and animals. Ecosystems exist on land and in water, with sizes ranging from a small puddle to an enormous swath of desert. Biome versus Ecosystem

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Rainforests