Gerbils and jerboas designedto survive in the searing deserts
MANY of the hundred-plus gerbil and jerboa species survive in quite arid conditions in the Sahara desert and other deserts in the world.
Jerboas are easily distinguishable by their huge ears. In the desert, domesticated species would be unable to survive the food irregularity and heat, but their wild ancestors and counterparts have a number of behavioural and anatomical adaptations that enable them to scrape by on the few resources available to them.
Although a number of colour variations have arisen, wild gerbils are pale brown. This form of colouration gives them camouflage in their environment, making them less likely to be detected by predators.
In order to minimise the levels of fluid that they lose, over time gerbils have evolved to only urinate relatively infrequently compared to some other, non-desert dwelling rodents.
Gerbils are excellent burrowers - they do it so much that even captive gerbils need to burrow in order to fill this deep evolutionary need. Living in a burrow enables gerbils to escape the intense heat of the day. The sand insulates their little nest, keeping it safe from the burning heat and helping it protect against the chill of a cloudless desert night.
The North African gerbil has long soft fur and a relatively long tail. The dorsal fur is cinnamon to orange-brown. Each hair has a grey base, a sandy or golden-brown terminal section and often a black tip.
The North African gerbil is found in Algeria, Egypt, Libya, Mali, Morocco, Niger, Sudan, Tunisia, and possibly Chad and Mauritania.Its habitat varies across its range, but in general it favours habitats with rocks and vegetation rather than sand.
The North African gerbil lives in a burrow that it digs and is a terrestrial and nocturnal mammal. The timing of breeding depends on location, but in Egypt coincides with the winter rains, and in North Sudan follows the short wet season in September to November. The litter size is about five. The diet of this rodent has not been studied.
The North African gerbil is a common species that flourishes in a range of different environments and in some locations, such as in Morocco, it is reckoned to be an agricultural pest species. The International Union for Conservation of Nature has rated the conservation status of this rodent as being of “least concern”.
On the other hand, the diminutive jerboa looks as though it were made from left-over spare parts of other animals, but it is nevertheless superbly adapted to harsh environments such as those of the Gobi and Sahara deserts. It holds membership in the Dipodinae, or “jumping rodents,” family, which includes several different genera. The jerboa belongs to one of three genera that include more than two dozen species, more than 20 of them in Asia.
Typically, the jerboa has a mouse- or rat-like head and body, cat-like sensory whiskers, owl-like eyes, squirrel-like to jackrabbit-like ears, kangaroo-like back legs, prairie dog-like forelegs and a disproportionally long, sometimes tufted, distinctive tail.
The skull of the jerboa is shaped much like that of a mouse or rat; nose, strong, adapted for tunnelling burrows for refuge; eyes, large, adapted for nocturnal activity; ears, proportionally large to very large, depending on species, and protected by bristly hairs; teeth, curved and grooved chisel-like incisors and strong molars, adapted for eating the tough plant materials of arid lands; sensory whiskers, long and adapted for feeling immediate surroundings in the darkness of night or within burrows.