Ensayo Gremios Salud

Survival of plants and animal in desert conditions

The harsh conditions in deserts are intolerable for most plants and animals. Despite these conditions, however, many varieties of plantsand animals have adapted to deserts in a number of ways. Most plant tissues die if their water content falls too low: the nutrients that feed plants are transmitted by water; water is a raw material inthe vital process of photosynthesis; and water regulates the temperature of a plant by its ability to absorb heat and because water vapor lost to the atmosphere through the leaves helps to lower planttemperatures. Water controls the volume of plant matter produced. The distribution of plants within different areas of desert is also controlled by water. Some areas, because of their soil texture,topographical position, or distance from rivers or groundwater, have virtually no water available to plants, whereas others do.

The nature of plant life in deserts is also highly dependent on thefact that they have to adapt to the prevailing aridity.

Animals also have to adapt to desert conditions, and they may do it through two forms of behavioral adaptation: they either escape orretreat. Escape involves such actions as aestivation, a condition of prolonged dormancy, or torpor, during which animals reduce their metabolic rate and body temperature during the hot season or during verydry spells.

Seasonal migration is another form of escape, especially for birds. The term retreat is applied to the escape behavior of desert animal, and usually assumes the pattern of a dailyrhythm.

Some animals have behavioral, physiological, and morphological adaptations that enable them to withstand extreme conditions. The sparse distribution of the feathers, however, also allowsconsiderable lateral air movement over the skin surface, thereby permitting further heat loss by convection. Furthermore, the birds orient themselves carefully with regard to the Sun and gently flap...