Table 1 Examples of environmental factors which make arid environments inhospitable for animal life, and associated challenges faced by living organisms
From: A rather dry subject; investigating the study of arid-associated microbial communities
Arid environmental factor | Challenges | Example animal adaptations |
|---|---|---|
Lack of food | Extreme seasonality of food sources Requirement for multiple different food sources, or in contrast, to specialise to a single food source Travel longer distances to find food Increased exposure to predators Depressed metabolism | Switch lifestyle to nocturnal to access more different food sources - potentially also with greater water content [9] |
Lack of water | Dehydration Reduced metabolic rate Reduced ability to manage body temperature Behavioural changes increase risk of predation i.e. sheltering to reduce water loss leading to exposure to predators | Reduce urine production and concentrate any produced [10] Store greater amounts of water in the body [11] Changes in activity patterns [12] |
Extremes of temperature | Hyperthermia ● Protein denaturation ● Dehydration from increased panting or sweating ● Multiple organ failure Hypothermia ● Frostbite ● Water in body freezing ● Metabolic rate falling below survival baseline ● Loss of heat from extremities | Tolerate increased temperatures through seeking shelter from the heat of the sun [13] Tolerate freezing through production of specialised compounds and antifreeze proteins [14] |
Extremes of salinity | Herbivores need ability to digest salty plant matter without losing excess water during digestion Need to maintain water balance in face of osmotic challenges from consuming salty water | Salt glands which can excrete salt from the body depending on dietary intake and internal osmotic balance [15] |
Elevated UV-C and UV-B exposure | Increased risk of genetic damage from UV irradiation of external body surfaces | Increased skin, fur or carapace pigmentation [16] |