In the balmy tropical Atlantic, everything from dolphins, manatees and whale sharks to sunbathing jellyfish thrive in the Caribbean's warm, sheltered waters, fringed with coral reefs and rich mangrove forests. But extreme heat in Africa unleashes terrifying hurricanes, causing chaos across the region.
Part one of two. Thirty years ago explorer Benedict Allen lived in Papua New Guinea with the Niowra, a remote people. Broadcast journalist Frank Gardner has always wished to see wild birds of paradise, so Benedict resolves to take him along. The duo set out through some of the most inhospitable terrain on the planet, negotiating swamps, mountains and crocodile-infested waters, heading into the cloud forest. Despite Frank requiring the use of a wheelchair following a shooting incident in 2004, Benedict determines to get him to their destination.
While most of the series has focused on conflict, this episode is all about co-operation. The suitably named social spiders spin one enormous, 30m web for the whole colony, a queen bee rules her hive with a strict hierarchy and some green ants show great team spirit to help build a nest together. There are no broken societies here. David Attenborough shifts the focus to bugs that prefer cooperation rather than conflict. They include burrowing cockroaches, the suitably named social spiders - which share a 30-metre web.
Young animals prepare for their first winter away from their parents, humpback whales return to Alaska's rich feeding grounds and salmon return to spawn in the rivers where they were hatched. But the returning salmon have to negotiate a path past hungry brown bears fattening themselves before they hibernate.