Dry tolerant plants and animals are able to cope with conditions where water is hard to find. Strategies include preventing its loss, storing for later use and being able to survive on less than normal. These adaptations aren't only important for organisms that live in tropical hot deserts. They're also necessary for those that inhabit the cold deserts of the polar regions, and non-desert areas that suffer from periodic or seasonal droughts. Cacti are among the most drought resistant plants on the planet and are able to store water in their stems and roots. Some can even survive years of drought after a single rainfall.

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