Ecosystems

Animals of the desert

Impressive cases of adaptation to this inhospitable habitat, where heat and drought are the main limitations to the development of life and also to the availability of food, can also be found in the animal kingdom.
During the summer or particularly long drought periods, some desert animals "aestivate", i.e. they reduce their activity by hiding under the rocks or underground, just as, in milder climates, many living beings hibernate in winter. Aestivating animals include, for instance, some species of reptiles and the desert snails which come to life only after rains: when moisture decreases, they hole up in their shells waiting for new rains in a dormant state that can last up to five years.
Butterflies, coleopters and desert cockroaches also adjust their life cycles to rainy times: the larvae come out of their eggs only when there is more food around after the rains.
Reduced activities can also be found during the day, especially at the hottest mid-day hours when all animals take refuge in the shadow.
Some large animals, such as ungulate mammals, carnivores, birds and flying insects, wander away or migrate to move from hotter and drier areas to more hospitable ones. For instance, the sand-grouses, partridge-like birds, move every day to go and drink in the oases or wherever they may find water. These birds can even drink brackish water.