Life at the limits – Wet and dry

In the Amazon forest, the largest rainforest on Earth, animals must deal with high rainfall and periodic flooding. They have to find clever ways to survive. The sloth spends most of its time hanging upside down in trees, eating leaves. To overcome constantly water-laden fur, the sloth’s fur grows in the opposite direction to other mammals. This enables it to shed rainwater quickly. And when permanent rain fills the rivers, these slow-moving mammals have to swim from tree to tree to find food. When ponds in Sri Lanka dry out at the height of summer they expose the last remaining fish to hungry crocodiles and storks. But when the banquet is over, predators must find food elsewhere – a dangerous undertaking because all around the land is drying up under the scorching sun. At the same time, the elephants of Sri Lanka are on the move. They need to find water – and quickly. In the desert of Namibia, rivers are mostly desiccated beds of sand. But sand grouse, oryx and giraffes find the last remaining pools of water. And drought can also be live-giving: along the sand banks of the fast evaporating Amur River, terns build their nests. Here, their offspring are safe from predators such as foxes or boars; but ironically, not from their own kind. In every extreme environment on Earth life is challenging, yet wildlife has evolved ingenious ways to survive and even thrive. ‘Life at the Limits’ is a celebration of nature’s ingenuity, against the odds.