Nanoscale hairs may help gecko skin trap moisture and slow evaporation

In a dry shrubland, a gecko sprints toward shelter. Its greatest danger is not a predator, although hawks circle overhead and sand cats wait in ambush. Rather, its most pressing concern is dehydration. Its skin is paper-thin; water can evaporate from its body into the dry air more quickly than it can replenish it. Fortunately, evolution has given it an adaptation: thin, nanoscopic hairs, called setulae, that cover its body and trap moisture.