Otocyon megalotis

The bat-eared fox (Otocyon megalotis) is a species of fox found on the African savanna, named for its large ears, which are used for thermoregulation. Fossil records show this canid first appeared during the middle Pleistocene, about 800,000 years ago. It is considered a basal canid species, resembling ancestral forms of the family. The bat-eared fox (also referred to as Delalande's fox, long-eared fox, big-eared fox, and black-eared fox) has tawny fur with black ears, legs, and parts of the pointed face. It averages 55 centimetres (22 in) in length (head and body), with ears 13 centimetres (5.1 in) long. It is the only species in the genus Otocyon. The name Otocyon is derived from the Greek words otus for ear and cyon for dog, while the specific name megalotis comes from the Greek words mega for large and otus for ear. Two allopatric populations (subspecies) occur in Africa. O. m. virgatus occurs from Ethiopia and southern Sudan to Tanzania. The other population, O. m. megalotis, occurs in the southern part of Africa. It ranges from southern Zambia and Angola to South Africa, and extends as far east as Mozambique and Zimbabwe, spreading into the Cape Peninsula and toward Cape Agulhas. Home ranges vary in size from 0.3 to 3.5 km2. The bat-eared fox commonly occurs in short grasslands, as well as the more arid regions of the savanna. It prefers bare ground and areas where grass is kept short by grazing ungulates. It tends to hunt in these short grass and low shrub habitats. However, it does venture into areas with tall grasses and thick shrubs to hide when threatened. In addition to raising their young in dens, bat-eared foxes use self-dug dens for shelter from extreme temperatures and winds. They also lie under acacia trees in South Africa to seek shade during the day. The bat-eared fox is predominantly an insectivore that uses its large ears to locate its prey. About 80–90% of their diet is harvester termites (Hodotermes mossambicus). When this particular species of termite is not available, they feed on other species of termites and have also been observed consuming other arthropods such as ants, beetles, crickets, grasshoppers, millipedes, moths, scorpions, spiders, and rarely birds, small mammals, reptiles, and fungi (the desert truffle Kalaharituber pfeilii). The insects they eat fulfill the majority of their water intake needs. The bat-eared fox refuses to feed on snouted harvester termites, likely because it is not adapted to tolerate termites' chemical defense. The teeth of the bat-eared fox are much smaller and reduced in shearing surface formation than teeth of other canid species. This is an adaptation to its insectivorous diet. Due to its unusual teeth, the bat-eared fox was once considered as a distinct subfamily of canids (Otocyoninae). However, according to more recent examinations, it is more closely related to the true foxes of the genus Vulpes. Other research places the genus as an outgroup which is not very closely related to foxes. The bat-eared fox is an old species that was widely distributed in the Pleistocene era. The teeth are not the bat-eared fox's only morphological adaptation for its diet. The lower jaw has a step-like protrusion called the subangular process, which anchors the large muscle to allow for rapid chewing. The digastric muscle is also modified to open and close the jaw five times per second. Bat-eared foxes usually hunt in groups, mostly in pairs and groups of three. Individuals forage alone after family groups break in June or July and during the months after cub birth. Prey is located primarily by auditory means, rather than by smell or sight. Foraging patterns vary between seasons and coincide with termite availability. In the midsummer, individuals begin foraging at sunset, continuing throughout the night, and fading into the early morning. Foraging is almost exclusively diurnal during the winter it usually occurs in patches, which match the clumped prey resources, such as termite colonies, that also occur in patches. Groups are able to forage on clumps of prey in patches because they do not fight each other for food due to their degree of sociality and lack of territoriality.