Planet Earth II

An indri, a type of lemur endemic to the forests of Madagascar, leaps from tree to tree.

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Spider monkeys are superbly adapted to life in the treetops. Their long arms and legs allow them to navigate the canopy with ease, using their prehensile tail for both balance and as an extra limb. For an infant spider monkey, the treetops can be a dangerous place to learn the ropes - a third of spider monkeys don't make it to adulthood. One young female is heading up the branches above the rest of her family and in the process figuring out which trees she can climb and which she cannot. Before she knows it, she's climbed too high; here the branches are further apart and she becomes stuck. Luckily, her cries for help are heeded by her father who climbs up next to his daughter positioning his body as a bridge, allowing her to latch onto him for safety.

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Male Sumatran gliding lizards are highly territorial over the best trees in the forests on which to hunt ants and other insects. Most disputes are settled with visual displays of strength, which each male does by extending and flexing a brightly-coloured dewlap on its neck. In one such contest, the loser demonstrates an extraordinary ability of these Draco lizards: he escaping his rival by leaping off of the tree and unfurling his patagia - thin membranes extending on either side of this body - that act as "wings" enabling the lizard to glide great distances before landing on another, hopefully unoccupied, tree trunk.

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Insects, like the bicoloured trailing ant, are a major part of the diet of Sumatran gliding lizards which compete to maintain territory over trees with a high concentration of ant prey.

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The sword-billed hummingbird's beak is longer than its body, allowing it to access nectar in flowers that other hummingbirds in Ecuador cannot. This does have some drawbacks however; other hummingbirds use their beaks to preen. The sword-billed hummingbird has adapted to use its feet instead to preen its body feathers. To keep its long beak clean, it rubs the length of it against the bark of a tree branch.

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It can rain so heavily in some jungles, such as those in Cantão State Park in Brazil, that for part of the year, the water level rises to 10 metres above the forest floor. Amazon river dolphins live in these wetlands. Almost completely blind, these dolphins navigate the murky waterways using sonar to hunt for fish. This population may represent an entirely new species.

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At the margins of the jungle in the Pantanal, lush vegetation supports large animals, such as capybara, the world's largest rodent. These animals can be seen resting on the sides of river banks when not in the water feeding on the vegetation. Still, they remain wary of predators such as jaguars that prowl the water's edge.

At the margins of the jungle in the Pantanal, lush vegetation supports large animals, such as giant otters.

Yacare caiman in the Pantanal of Brazil can grow up to 10 feet long. Despite their size, caiman can still be hunted by jaguars. Even after being caught, the caiman is able to trash in the water or snap its jaws in an attempt to escape, that is until the jaguar delivers the killing blow to the back of the caiman's skull where it is most vulnerable.

The lush vegetation of the Pantanal supports a great number of prey animals, which in turn supports a high density of jaguars. These big cats fiercely defend their territories. To hunt prey such as capybara, jaguars employ stealth while either partially submerged in the water or hidden in the riverside foliage. The capybara are wary and alert, so many hunts end in failure. A large male jaguar disposes of stealth and instead hunts caiman. He pounces from above directly into the water to subdue his prey and delivers a killing blow to the back of the caiman's skull before dragging the carcass up the riverbank.

Among the many examples of mimicry as a means of evading predators, one of the most amazing is the leaf-tailed gecko of Madagascar. Its body effectively disappears into the profile of the tree branch, as it mirrors not only the colour but the texture of the bark and lichen around it.

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Glass frogs are almost transparent. By staying very still, they go unnoticed by potential predators, such as katydid crickets. A male reticulated glass frog lies flat against a leaf, guarding several clutches of eggs that he has fertilised with various females over the previous weeks. The clutches at the very bottom of the leaf contain the most developed tadpoles. When attacked by predatory wasps, these tadpoles are able to sense danger and wriggle out of their egg sacs to drop into the water below. The less-developed eggs towards the top of the leaf are more vulnerable. The male's back, however, is covered in a pattern that resembles a clutch of glass frog eggs and acts as a decoy; as confused wasps move towards the male to investigate, he uses his powerful legs to kick and swat the wasps away. Though the stings of the wasps would be lethal, the male glass frog is able to save most of his clutch.

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Crickets, such as the rhinoceros katydid, are potential predators of glass frogs - if they can spot them.

Some species of predatory wasps specialise in hunting frogs' eggs. While clutches of still-developing glass frog tadpoles attached to the side of a leaf may appear to be an easy meal, these wasps have to contend with two challenges. First, the tadpoles that are close to being fully grown can sense the wasp attacking and actively wriggle out of their egg sacs to drop into the water below. Second, the eggs are often guarded by a male glass frog who vigorously defends his offspring with his powerful kicking legs and has a pattern on his back that resembles a clutch of eggs, which confuses the wasps.

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The fungus Neonothopanus gardneri emit a green glow at night. This light attracts insects such as male click beetles, which mistake the fungus' glow for a female. As the male beetle climbs onto the fungus to continue to search for the female, the fungal spores attach to the beetle and are subsequently dispersed throughout the forest.

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The railroad worm (really a beetle larva) emits lights from its body as a signal to would-be predators of its poisonous nature. These larvae hunt millipedes on the forest floor. Once they happen upon the trail of one, they are able to switch off the yellow-green lights on the sides of their bodies, leaving only their red headlight on. Millipedes are unable to see red light, so the railroad worm is able to hunt stealthily.

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Millipedes are the favoured prey of railroad worm beetle larvae. These larvae emit red light, which millipedes are unable to see, from their heads while hunting.

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Male red birds-of-paradise compete with one another to attract a female in the treetops. While the males "dance" by shaking their feathers and tail wires, a curious female eyes them up carefully.



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The Wilson's bird-of-paradise starts its courtship display by clearing a well-lit space on the forest floor of leaves. Then, he begins to call for a female and lies in wait. Once a potential mate arrives, the male takes up position at the centre of the cleared space and the female perches directly above the male. He puffs out his chest feathers to show its dazzling green iridescence, made even more stiking by the absence of green leaves around them.

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Each morning, a family of indris, led by a dominant female, comes together in the treetops to sing, as a way of strengthening bonds. Indris have become highly specialised to live in Madagascar's forests. Yet, in the 10 years since the lead female was born, 10,000 square kilometres of rainforest have been destroyed. Now, the number of indri families that live here has halved.

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