Adaptations to Life in the Namib Desert

Abstract

AbstractThe Namib Desert, as represented in Iona National Park, provides a living museum of the adaptations of animals and plants to extreme environments. This chapter illustrates the morphological, behavioural and physiological adaptations resulting from natural selection in response to extreme conditions of aridity and temperature. The role of water is described as the ‘currency of life’ in the Namib. Surface area to volume ratios in animals and plants determine rates of water loss through evaporation, with many succulent plant species displaying the short, stout water conserving pachycaul life form. Water capture from fog is achieved by ‘fog basking’ and ‘sand trenching’ by beetle species, and by grazing at night (when water content of grasses is highest) by antelope. Competition for food in low productivity environments such as the Namib takes many forms, including habitat partitioning, cooperative behaviour and efficient food storage mechanisms. Unique Namib natural phenomena, such as the ‘fairy circles’ - bare patches in extensive desert grasslands - have received intensive study by multiple research groups. Arguments proposing divergent hypotheses demonstrate the scientific method in action.