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The Antilopinae is a diverse assemblage of small and
medium-sized antelopes native to open, arid environments in Africa and Eurasia.
While widespread in Africa, this subfamily also has a dozen species spread
across Eurasia (only one other Aegodontia subfamily remains successful outside
of Africa). The Antilopinae arose 17-16 million years ago; the first fossils
appear in Eurasia, with evidence in African deposits beginning 13.5 million
years ago.
Several features unite the species within this group, notably the skull structure, dentition (closely resembling fossils from 12 million years ago), and presence of solid horn cores. The preorbital glands are well developed in most species: they are composed of a spherical mass of glandular tissue located in front of each eye. These glands secrete a sticky black substance which is carried by a central duct to a circular patch of bare skin. The opening of this duct is covered by a purse-like fold of skin which can be opened wide during the deposition of secretions. There are two traditionally recognized tribes, each of which is discussed separately below:
The Antilopini (gazelles) are medium-sized bovids which are highly evolved for a cursorial (running) existence in open environments. There is little sexual dimorphism in body size or coloration. Horns are generally present in both sexes of this tribe, but they are lacking in females of some genera. There are often striking markings on the face, flanks, and/or rump. The mating system of all species is polygynous. The Antilopini traditionally includes the genus Procapra. However, the three species in this genus appear to be as different from the gazelles as they are from the dwarf antelope - no new tribe has yet been ascribed to these antelope. The Neotragini have traditionally been grouped together on the basis of small body size (all species weigh less than 30 kg); all genera also possess "primitive" characteristics. However, following molecular analysis, this classification seems to be erroneous. While most of the dwarf antelope are closely related, the genera Neotragus and Oreotragus, while clearly within the Aegodontia, do not have clear evolutionary affinities with any subfamily, including the Antilopinae. Indeed, it has been proposed that both of these genera are unique lineages, and may have diverged from other bovids during the early Miocene. They are shown in the phylogeny below as basal to the subfamily Antilopinae in order to put this discussion into perspective: as of yet, there is no consensus as to the names of their respective subfamilies. With the exclusion of Neotragus and Oreotragus, the traditional tribe Neotragini is now polyphyletic. Naming conventions have not yet been resolved (can there be a Neotragini that excludes the genus Neotragus?), and thus the classical names are still used here. Neotragus is a primarily forest-dwelling genus, with a hare-like build and backward-slanting horns (the preorbital glands lack a surface fold of skin). Oreotragus is a specialized rock-dweller, inhabiting kopjes and cliffs adjacent to savannahs. The remaining dwarf antelopes (Dorcatragus, Madoqua, Ourebia, and Raphicerus, which DO form a taxonomically-valid grouping) all inhabit relatively arid environments (savannahs and scrub mosaic), and have several adaptations for conserving water, notably nasal panting. All are selective feeders and rarely (if ever) need to drink. Unlike the Antilopini, they often form monogamous pairs. Short, vertical, spike-like horns are found only in males (never in females). |
(From Hernandez-Fernandez and Vrba, 2005)
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Oreotragus
oreotragus
Ourebia ourebi Madoqua guentheri Madoqua piacentinii Madoqua saltiana Raphicerus melanotis Raphicerus sharpei Procapra picticaudata Procapra przewalskii Antidorcas marsupialis Eudorcas albonotata Eudorcas thomsonii Nanger granti Gazella bennettii Gazella bilkis Gazella arabica Gazella gazella Gazella saudiya |
or jump to the Antilopinae Species List