What's special about the physiological ecology of desert organisms?

Dormancy and flexible schedules for productive processes may be critical in allowing plants and animals to survive sites where unfavourable conditions are protracted. Thresholds that protect such organisms from initiating reproductive activity when rainfall is insufficient for successful completion can be important. Perspectives are given on such issues with respect to desert plants (particularly the ecology and evolution of crassulacean acid metabolism), desert invertebrates, amphibians, and endotherms (including a section of water and food in mammalian herbivores). -P.J.Jarvis