The family Procaviidae (hyraxes or "rock rabbits") is the only family in the order Hyracoidea. Although hyraxes superficially resemble large rodents or rabbits, both morphological and molecular phylogenetic studies indicate that they are actually most closely related to elephants and sea cows. The clade including these three groups is known as Paenungulata and Paenungulata together with sengis (elephant shrews), aardvarks, tenrecs, and golden moles comprise Afrotheria. The family was named "Procaviidae" ("before the guinea pigs") in the late 1700s to reflect a perceived resemblance to guinea pigs. The name hyrax is similarly misleading as it is derived from a Greek word meaning "shrew mouse".
Three genera of living hyraxes are recognized: Procavia (Rock Hyrax), Heterohyrax (Bush Hyrax), and Dendrohyrax (tree hyraxes). Hoeck (2011) recognizes a single species each in Procavia and Heterohyrax and three species of Dendrohyrax, but notes that further study is likely to confirm additional cryptic species in each of these genera.
Hyraxes tend to use communal latrines, resulting in crystallized deposits that whiten the cliff faces below. These middens of accumulated faecal pellets and a brown tar-like substance known as hyraceum (a urinary product composed of organic elements, soluble salts, and carbonates; Leon and Belonje 1979) trap plant material, pollen, and animal remains. They have been described as "palaeoenvironmental archives" for southern Africa (Chase et al. 2012). Where protected from rain, these accumulated deposits may be more than a meter thick and several meters across. Hyraceum was valued as medicine by several South African tribes and by European settlers and has been used in perfume manufacture.
Hyraxes are endemic to Africa, with the exception of the Rock Hyrax, whose range extends eastward to Syria and the Arabian Peninsula. Rock Hyraxes live in a wide range of habitats, from arid deserts to rainforest and from sea level to the alpine zone of Mount Kenya at 3200-4200 m. Bush Hyraxes are found from Eritrea and Sudan south to South Africa and Namibia. Rock and Bush Hyraxes require the presence of suitable refuges in kopjes, large boulder piles, or cliffs. In several parts of Africa, Bush and Rock Hyraxes co-occur. In Serengeti National Park, for example, they are the most important resident herbivores of the kopjes. Tree hyraxes occur in appropriate habitat in West, Central, and East Africa, as well as in southern Africa. They are found in arboreal habitats, but in some areas are also rock-dwellers.
Rock and bush hyraxes are diurnal and gregarious, but tree hyraxes are generally nocturnal and mainly solitary. Hyrax activity patterns are strongly influenced by ambient temperature and predator exposure. Bush and Rock Hyraxes sometimes occur in mixed-species groups and respond to each other's alarm calls. Bush and tree hyraxes are excellent climbers and jumpers.
Hyraxes are herbivores, feeding mainly on leaves, twigs, fruit, and bark. Rock Hyraxes often feed heavily on grass, but the other hyraxes rarely do.
Although hyrax populations are believed to be generally stable, the tree hyraxes are hunted for fur and food and are likely very sensitive to habitat degradation as they are confined to primary forests.They also have uses in traditional rituals and traditional medicine.
(Hoeck 2011 and references therein)