Capra is a
genus of
mammals, the goats, comprising ten
species, including the
markhor and several species known as
ibexes. The
domestic goat (Capra hircus) is a
domesticatedspecies derived from the wild goat (Capra aegagrus). Evidence of goat domestication dates back more than 8,500 years.
Wild goats are animals of
mountain habitats. They are very agile and hardy, able to climb on bare rock and survive on sparse vegetation. They can be distinguished from the genus Ovis, which includes sheep, by the presence of scent glands close to the feet, in the groin, and in front of the eyes, and the absence of other facial glands, and by the presence of a beard in some specimens, and of hairless
calluses on the knees of the forelegs.[1]
Taxonomy
All members of the genus Capra are
bovids (members of the family Bovidae), and more specifically caprines (subfamily
Caprinae). As such they are
ruminants, meaning they chew the cud, and have four-chambered stomachs which play a vital role in digesting, regurgitating, and redigesting their food.
The genus has sometimes been taken to include Ovis (sheep) and Ammotragus (
Barbary sheep),[2] but these are usually regarded as distinct genera, leaving Capra for ibexes. In this smaller genus, some authors have recognized only two species, the markhor on one side and all other forms included in one species on the other side.[3] Today, nine wild species are usually accepted to which is added the domestic goat:[4]
West Asian ibex also known as the wild goat (Capra aegagrus)
The
goats of the genus Capra have complex systematic relationships, which are still not completely resolved. Recent studies based on
mitochondrial DNA suggest that the Asian ibex and the Nubian ibex represent distinct species, which are not very closely related to the physically similar Alpine ibex. The Alpine ibex forms a group with the Iberian ibex. The West Caucasian tur appears to be more closely related to the wild goat than to the East Caucasian tur. The markhor is relatively little separated from other forms—previously it had been considered to be a separate branch of the genus.[7]
Almost all wild goat species are
allopatric (geographically separated)—the only geographical overlaps are the wild goat (Capra aegagrus) with the East Caucasian tur (Capra cylindricornis), and the markhor (Capra falconeri) with the Asian ibex (Capra sibirica). In both cases, the overlapping species do not usually interbreed in the wild, but in captivity, all Capra species can interbreed, producing fertile offspring.[8]
Along with sheep, goats were among the first
domesticated animals. The domestication process started at least 10,000 years ago in what is now northern
Iran.[10] Easy human access to goat hair,
meat, and
milk were the primary motivations. Goat skins were popularly used until the
Middle Ages for water and
wine bottles when traveling and
camping, and in certain regions as
parchment for writing.
^Ansell, W. F. H. 1972. Order Artiodactyla. Part 15. Pp. 1–84, in The mammals of Africa: An identification manual (J. Meester and H. W. Setzer, eds.) [issued 2 May 1972]. Smithsonian Institution Press, Washington, D.C., not continuously paginated. (quoted in
Grubb, P. (2005).
Wilson, D. E.; Reeder, D. M. (eds.).
Mammal Species of the World: A Taxonomic and Geographic Reference (3rd ed.). Baltimore, MD: Johns Hopkins University Press.
ISBN0-8018-8221-4.
OCLC62265494.)
^Nathalie Pidancier, Steve Jordan, Gordon Luikart, Pierre Taberlet: Evolutionary history of the genus Capra (Mammalia, Artiodactyla): Discordance between mitochondrial DNA and Y-chromosome. Molecular Phylogenetics and Evolution 40 (2006) 739–749
online
^Phylogenetic Reconstructions in the Genus Capra (Bovidae, Artiodactyla) Based on the Mitochondrial DNA Analysis. Russian Journal of Genetics, 2007, Vol. 43, No. 2, pp. 181–189.
online
^V. G. Heptner: Mammals of the Sowjetunion Vol. I UNGULATES. Leiden, New York, 1989
ISBN90-04-08874-1
^Melinda A. Zeder, Brian Hesse: The Initial Domestication of Goats (Capra hircus) in the Zagros Mountains 10,000 Years Ago. Science 24 March 2000: Vol. 287. no. 5461, pp. 2254–2257
online abstract