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            Home | Ungulates | About Us | Glossary | Links | Search | Contact Us
            An Ultimate Ungulate Fact Sheet
            Subfamily Alcelaphinae
            Sassabies, hartebeests, and wildebeests
            The Alcelaphinae is a group of large, nomadic antelope native to Africa. While some authors (e.g. Walther, 1990) recognize only five species in this subfamily, the latest taxonomic revisions recognize ten modern species of Alcelaphine antelope. This subfamily is a relatively recent evolutionary development - the first fossils appear between 5 and 4.5 million years ago in Africa. After initial appearing, this subfamily diversified with extraordinary speed - 2 million years ago, the Alcelaphinae reached a peak in their diversity, with at least 8 genera and over 15 species.

            All of the species in this subfamily are specialized grazers, adapted to living at high population densities and utilizing an abundant but unstable food supply. While the Alcelaphinae ranged across much of Africa in huge herds as little as a few centuries ago, their present numbers and distribution have been reduced at the hands of humans. Only the wildebeest and topi populations in East Africa approach their former numbers.

            Among the Alcelaphinae, there is little sexual dimorphism aside from size: males tend to be10-20% larger than females. All species have a gawky, awkward appearance. The legs are long and thin, being well adapted for a cursorial existence on the open plains. The forequarters are noticeably enlarged and the back slopes down towards the hindquarters, especially in the hartebeests (Alcelaphus sp.). Pedal scent glands are found in the forefeet only. The face is elongated (compensating for the high forequarters and disproportionately short neck, and thereby permitting these species to graze). Preorbital glands are well-developed in both sexes. The lyrate or double-curved horns are found in both males and females of all species (those of males tend to be longer and thicker).

            The young of all species are born a light tan color and are precocious "followers" (sticking close to their mothers after birth). In several species (notably the wildebeests, Connochaetes sp.) neonates never have a "hiding" phase and can keep up with their mothers within a day of being born. Several species of Alcelaphine antelope are used extensively in game ranching, including the red hartebeest, blue wildebeest, and blesbok.

            The Alcelaphinae Family Tree
            Branch lengths are not proportional to time
            (Adapted from Hernandez-Fernandez and Vrba, 2005)

             

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            Bovidae

            Alcelaphus buselaphus

            Connochaetes gnou

            Connochaetes taurinus

            Beatragus hunteri

            Damaliscus lunatus

            Damaliscus pygargus

            Click on the species above to learn more,
            or jump to the Alcelaphinae Species List
            Literature Cited

            Alden, P. C., R. D. Estes, D. Schlitter, and B. McBride. 1995. National Audubon Society Field Guide to African Wildlife. New York: Chanticleer Press.

            Estes, R. D. 1991. The Behavior Guide to African Mammals: including hoofed mammals, carnivores, primates. Los Angeles: University of California Press.

            Hernandez-Fernandez, M., and E. S. Vrba. 2005. A complete estimate of the phylogenetic relationships in Ruminantia: a dated species-level supertree of the extant ruminants. Biological Review; 80: 269-302.

            Kingdon J. 1997. The Kingdon Field Guide to African Mammals. London and New York: Academic Press, NaturalWorld.

            Walther, F. R. 1990. Hartebeests. In Grzimek's Encyclopedia of Mammals. Edited by S. P. Parker. New York: McGraw-Hill. Volume 5, pp. 418-436.

            Vrba, E. S., and G. B. Schaller. 2000. Phylogeny of Bovidae based on behavior, glands, skulls, and postcrania. In Antelopes, Deer, and Relatives. Edited by E.S.Vrba and G.B.Schaller. New Haven & London: Yale University Press. pp. 203-222.

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