ADAPTATIONS OF PLANTS TO ARIDITY

ADAPTATIONS OF ANIMALS TO ARIDITY

INTERACTIONS BETWEEN SPECIES

HUMANS IN THE DESERT

CONCLUDING REMARKS

At its origins, life evolved in water, and water is the most crucial element for the survival of all living organisms. Thus, it is no surprise that some of the most remarkable adaptations for survival are found in desert species, that is, in the environments where water is most scarce (Louw and Seely 198 ). The short pulses of abundance that contrast sharply with the background condition of aridity and scarcity are the major force that has driven evolution, natural selection, and adaptation in desert biota. Plants and animals are adapted to these seasonal strokes. Natural selection and evolution have moulded in very precise ways the life-forms of desert organisms in their harsh and unpredictable environment. Furthermore, because most deserts of the world have developed in relative isolation from each other, many of their constituent species have evolved from different ancestors (Morton 1979). Thus, deserts are prime ecosystems to study and understand the phenomenon of convergent evolution - the development of similar growth forms and adaptations derived from different ancestors (Table 1. , Figure 1.11).