The highest mountaintops are covered with snow all year round. Those that lie in tropical regions, such as Kilimanjaro in Africa, can have hot, steamy rainforest at their foothills and freezing night-time temperatures at their summits. At high altitudes the sunlight is intense. There are strong, cold winds and a lack of oxygen in the air. Despite these dangers, mountains can host a wide variety of living things that have adapted to such harsh conditions.

Mammals and birds

Small mammals, such as the pika in Asia or the rock hyrax in Africa, live in burrows or rocky outcrops to protect themselves from the worst of the cold and wind. Many also hibernate during the winter. Larger animals have thick fur or woolly coats to keep out the cold. Grazing animals, such as sheep and goats, live at the highest altitudes. Their nimble hooves are able to negotiate even the most treacherous slopes. They are preyed upon by wolves, snow leopards and cougars or mountain lions.

Yak

The largest animal in the Himalayas, the yak also has thick fur, with another coat of long hair on top. This keeps the animals so warm that they have to move higher up the mountains to cooler areas in the summer. They are well adapted to altitudes of between 3000 and 5000 metres (about 10,000 and 16,000 feet) and actually suffer from heat exhaustion in temperatures above 15°C. Most yak, a type of bovid (cattle), are domesticated, but a few hundred wild yak still survive in the Himalayas.

Andes wildlife

High above the Andes mountain range in South America, the Andean condor, one of the biggest birds in the world, soars for many kilometres without flapping its wings. As it soars, it searches for carrion, its principal diet. In between the summits are high, grassy plateaux, where guanacos, wild relatives of the llama, roam.