Subfamily
Alcelaphinae
Sassabies, hartebeests, and
wildebeests |
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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)
Click on the species above to learn
more,
or jump to the Alcelaphinae Species
List
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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.
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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