In the Namib Desert, plants and animals survive because they have adapted to the extreme conditions.
Plants and trees often have very deep roots – for example, the camelhorn – which tap into ground water.
Many plants are able to store water in their trunks or leaves. Succulents – such as the half plant, half human - often protect the precious water in their swollen leaves with spines or sometimes with toxins. Other plants avoid being eaten by camouflaging themselves – lithops look like stones.
Leaves are usually small or few – the Welwitschia mirabilis only ever grows two. Some leaves have waxy coatings to stop moisture escaping or they can have surface hairs which trap still air and reduce any water loss through evaporation.
Many desert plants are also extremely slow-growing, stopping any growth during periods of high temperatures. Seeds and flowers can be inactive for long periods and only spring to life after rainfall.
Unlike plants, animals can move to escape the heat. Some migrate to cooler regions during the hottest months and only return after rain.
Many permanent residents of the desert simply retreat from the hot sun during the day, vanishing into burrows or nests until the cooler hours. Weaver birds are one example; their communal nests not only shade them from the heat of the day but also insulate them during the cold nights.
Other animals have learnt to shield themselves from the sun – the African ground squirrel uses its tail as a parasol, while the sand-diving lizard ‘dances’ across hot surfaces by lifting its legs at frequent intervals.
With water extremely scarce, the dune beetles of the Namib desert sit for hours in the morning fog which forms along the coastline (caused by the cold Benguela current offshore). This period of seeming inactivity allows water to condense on their bodies and the beatles then periodically tunnel the liquid into their mouths with their legs.
The oryx which lives in desert regions excavates waterholes and maintains them every year. The bodies of these antelopes are so efficient at absorbing water, their urine is produced in pellet form.