Adaptations of the aardvark for survival in the Karoo: a review

Abstract

Aardvarks are found in a wide range of habitats in sub-Saharan Africa, from semi-arid zones in the Nama Karoo to high rainfall areas of tropical rainforests. They are not, therefore, specifically adapted to living in dry or wet conditions; rather, being committed nocturnal and fossorial, myrmecophages, they have evolved anatomical, physiological and behavioural adaptations that allow them to feed on ants and termites. These adaptations allow aardvarks to inhabit many areas as long as sufficient prey is available. Feeding adaptations include specialised snout anatomy and a very keen sense of smell to find prey underground; a strong body structure and digging apparatus to dig into subterranean nests or termitaries; a long vermiform tongue and large salivary glands to extract prey from inside their nests; and a muscular stomach to grind up the food. The low rainfall of the Nama Karoo does not present a problem for aardvarks because they meet all their water requirements through their diet, while the strong seasonal temperature variations that could place considerable stresses on aardvarks are avoided by the judicious use of burrows. Nocturnal activity patterns allow aardvarks to conduct digging activities under relatively cool conditions, thus avoiding hyperthermia due to body heat production during hot conditions, while the diurnal activity patterns of most prey species means that they are inactive when aardvarks are foraging and can, therefore, be acquired more efficiently.