The History and Domestication of Goats

Goats (Capra hircus) were among the first domesticated animals, adapted from the wild bezoar ibex (Capra aegagrus) in western Asia. Bezoar ibexes are native to the southern slopes of the Zagros and Taurus mountains in Iran, Iraq, and Turkey. Evidence shows that goats spread globally and played an important role in the advancement of Neolithic agricultural technology wherever they went. Today, over 300 breeds of goats exist on our planet, living on every continent except Antarctica. They thrive in an astonishing range of environments, from human settlements and tropical rainforests, to dry, hot deserts and cold, hypoxic, high altitudes. Because of this variety, the domestication history was a bit obscure until the development of DNA research. Where Goats Originated Beginning between 10,000 and 11,000 Before Present (BP), Neolithic farmers in areas of the Middle East and Western Asia started keeping small herds of ibexes for their milk and meat; dung for fuel; and hair, bone, skin, and sinew for clothing and building materials. Domestic goats were recognized archaeologically by: Their presence and abundance in regions well beyond western AsiaPerceived changes in their body size and shape (morphology)Differences in demographic profiles from feral groupsStable isotope evidence of dependence on year-round fodders. Archaeological data suggests two distinct places of domestication: the Euphrates river valley at Nevali Çori, Turkey (11,000 BP), and the Zagros Mountains of Iran at Ganj Dareh (10,000 BP). Other possible sites of domestication posed by archaeologists included the Indus Basin in Pakistan at (Mehrgarh, 9,000 BP), central Anatolia, the southern Levant, and China. Divergent Goat Lineages Studies on mitochondrial DNA sequences indicate there are four highly divergent goat lineages today. This would mean either that there were four domestication events, or that there is a broad level of diversity that was always present in the bezoar ibex. Additional studies suggest the extraordinary variety of genes in modern goats arose from one or more domestication events from the Zagros and Taurus mountains and the southern Levant, followed by interbreeding and continued development in other places. A study on the frequency of genetic haplotypes (gene variation packages) in goats suggests that there may have been a Southeast Asian domestication event as well. Its also possible that, during the transport to Southeast Asia via the steppe region of central Asia, goat groups developed extreme bottlenecks which resulted in fewer variations. Goat Domestication Processes Researchers looked at stable isotopes in goat and gazelle bones from two sites on either side of the Dead Sea in Israel: Abu Ghosh (the Middle Pre-Pottery Neolithic B (PPNB) site) and Basta (the Late PPNB site). They showed that gazelles (used as a control group) eaten by the occupants of the two sites maintained a consistently wild diet, but goats from the later Basta site had a significantly different diet than goats from the earlier site. The main difference in the oxygen- and nitrogen-stable isotopes of the goats suggests that Basta goats had access to plants that were from a wetter environment than where they were eaten. This would likely result from the goats being either herded to wetter environments during some part of the year,  or provided fodder from those environments. This indicates that people managed goats—herding them from pasture to pasture or feeding them, or both—by as early as around 9950 cal BP. This would have been part of a process that began earlier still, perhaps during the early PPNB (10,450 to 10,050 cal BP) and coinciding with reliance on plant cultivars. Significant Goat Sites Important archaeological sites with evidence for the initial process of goat domestication include Cayà ¶nà ¼, Turkey (10,450 to 9950 BP), Tell Abu Hureyra, Syria (9950 to 9350 BP), Jericho, Israel (9450 BP), and Ain Ghazal, Jordan (9550 to 9450 BP). Resources and Further Reading Fernà ¡ndez, Helena, et al. â€Å"Divergent mtDNA Lineages of Goats in an Early Neolithic Site, Far From the Initial Domestication Areas.† Proceedings of the National Academy of Sciences, Edited by Ofer Bar-Yosef, vol. 103, no. 42, 17 Oct. 2006, pp. 15375-15379.Gerbault, Pascale, et al. â€Å"Evaluating Demographic Models for Goat Domestication Using mtDNA Sequences.† Anthropozoologica, vol. 47, no. 2, 1 Dec. 2012, pp. 64-76.Luikart, Gordon., et al. â€Å"Multiple Maternal Origins and Weak Phylogeographic Structure in Domestic Goats.† Proceedings of the National Academy of Sciences, Edited by Henry Harpending, vol. 98, no. 10, 8 Mar. 2001, pp. 5927-5932.Makarewicz, Cheryl, and Noreen Tuross. â€Å"Finding Fodder and Tracking Transhumance: Isotopic Detection of Goat Domestication Processes in the Near East.† Current Anthropology, vol. 53, no. 4, Aug. 2012, pp. 495-505.Naderi, Saed, et al. â€Å"The Goat Domestication Process Inferred From Large-Scale Mito chondrial DNA Analysis of Wild and Domestic Individuals.† Proceedings of the National Academy of Sciences, Edited by Kent V. Flannery, vol. 105, no. 46, 18 Nov. 2008, pp. 17659-17664.Naderi, Saeid, et al. â€Å"Large-Scale Mitochondrial DNA Analysis of the Domestic Goat Reveals Six Haplogroups with High Diversity.† PLoS ONE, Edited by Henry Harpending, vol. 2, no. 10, 10 Oct. 2007, pp. 1-12.Nomura, Koh, et al. â€Å"Domestication Process of the Goat Revealed by an Analysis of the Nearly Complete Mitochondrial Protein-Encoding Genes.† PLoS ONE, Edited by Giovanni Maga, vol. 8, no. 8, 1 Aug. 2013, pp. 1-15.Vahidi, Sayed Mohammad Farhad, et al. â€Å"Investigation of the Genetic Diversity of Domestic .† Genetics Selection Evolution, vol. 46, no. 27, 17 Apr. 2004, pp. 1-12.Capra Hircus Breeds Reared Within an Early Goat Domestication Area in IranZeder, Melinda A. â€Å"A Metrical Analysis of a Collection of Modern Goats (.† Journal of Archaeological Sci ence, vol. 28, no. 1, Jan. 2001, pp. 61-79.Capra Hircus Aegargus and C. H. Hircus) From Iran and Iraq: Implications for the Study of Caprine DomesticationZeder, Melinda A., and Brian Hesse. â€Å"The Initial Domestication of Goats (Capra Hircus) in the Zagros Mountains 10,000 Years Ago.† Science, vol. 287, no. 5461, 24 Mar. 2000, pp. 2254-2257.