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All cattle descend from one small herd, study finds

March 27, 2012
Courtesy of University College London
and World Science staff

All liv­ing cat­tle de­scend from as few as 80 an­i­mals do­mes­ti­cat­ed from wild ox­en in the Near East some 10,500 years ago, ac­cord­ing to a new ge­net­ic stu­dy.

Sci­en­tists ex­tracted DNA from the bones of do­mes­tic cat­tle found at Ira­ni­an ar­chae­o­log­i­cal sites. The sam­ples came from a re­gion where ar­chae­o­lo­gists be­lieve cat­tle were first do­mes­ti­cat­ed, and from a time not long af­ter farm­ing was in­vented.

All liv­ing cat­tle de­scend from as few as 80 an­i­mals do­mes­ti­cat­ed from wild ox­en in the Near East some 10,500 years ago, ac­cord­ing to a new ge­net­ic stu­dy. (Im­age cour­tesy U.S.D.A.)


The re­search­ers stud­ied how small dif­fer­ences in the DNA of those cat­tle, as well as liv­ing cat­tle, could have aris­en giv­en known dif­fer­ences in popula­t­ion his­to­ries. Us­ing com­put­er sim­ula­t­ions they found that the DNA varia­t­ions could only have aris­en if a small num­ber of an­i­mals, about 80, were ori­gin­ally do­mes­ti­cat­ed from wild ox­en.

The study ap­pears in the cur­rent is­sue of the jour­nal Mo­lec­u­lar Bi­ol­o­gy and Ev­o­lu­tion

“This is a sur­pris­ingly small num­ber of cat­tle. We know from ar­chae­o­log­i­cal re­mains that the wild an­ces­tors of mod­ern-day cat­tle, known as au­rochs, were com­mon through­out Asia and Eu­rope, so there would have been plen­ty of op­por­tun­i­ties to cap­ture and do­mes­ticate them,” said Mark Thom­as, ge­net­icist and an au­thor of the study based at Uni­vers­ity Col­lege Lon­don. 

“Wild au­rochs are very dif­fer­ent beasts from mod­ern do­mes­tic cat­tle,” added Jo­a­chim Burg­er, an au­thor of the study based at the Uni­vers­ity of Mainz, Ger­ma­ny. “They were much big­ger than mod­ern cat­tle, and would­n’t have had the do­mes­tic traits we see to­day, such as docil­ity. So cap­tur­ing these an­i­mals in the first place would not have been easy, and even if some peo­ple did man­age to snare them alive, their con­tin­ued man­agement and breed­ing would still have pre­sented con­si­der­able chal­lenges un­til they had been bred for smaller size and more doc­ile be­hav­ior.”

Ruth Bol­lon­gi­no of France’s Na­t­ional Cen­ter for Sci­en­tif­ic Re­search and the Uni­vers­ity of Mainz, Ger­ma­ny, lead au­thor of the stu­dy, said a hot cli­mate made it a chal­lenge to get use­a­ble DNA sam­ples.

“Get­ting re­li­a­ble DNA se­quences from re­mains found in cold en­vi­ron­ments is rou­tine,” she ex­plained. “That is why mam­moths were one of the first ex­tinct spe­cies to have their DNA read. But get­ting re­li­a­ble DNA from bones found in hot re­gions is much more dif­fi­cult be­cause tem­per­a­ture is so crit­i­cal for DNA sur­viv­al. This meant we had to be ex­tremely care­ful that we did not end up read­ing con­tam­i­nat­ing DNA se­quences from liv­ing, or only re­cently dead cat­tle.”

Ar­chae­o­log­i­cal stud­ies on the num­ber and size of pre­his­tor­ic an­i­mal bones have found that cat­tle, goats, sheep and pigs were all first do­mes­ti­cat­ed in the Near East. But how many an­i­mals were do­mes­ti­cat­ed for any of those spe­cies is a much harder ques­tion to an­swer.

“In this study ge­net­ic anal­y­sis al­lowed us to an­swer ques­tions that un­til now ar­chae­o­lo­gists would not even at­tempt to ad­dress,” said Jean-Denis Vi­gne a bio-ar­chae­o­lo­gist at the Na­t­ional Cen­ter in France and co-au­thor of the stu­dy. “A small num­ber of cat­tle pro­gen­i­tors is con­sist­ent with the re­strict­ed ar­ea for which ar­chae­o­lo­gists have ev­i­dence for early cat­tle do­mes­tica­t­ion cir­ca 10,500 years ago. This re­strict­ed ar­ea could be ex­plained by the fact that cat­tle breed­ing, con­tra­ry to, for ex­am­ple, goat herd­ing, would have been very dif­fi­cult for mo­bile so­ci­eties, and that only some of them were ac­tu­ally sed­en­tary at that time in the Near East.”


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All living cattle descend from as few as 80 animals that were domesticated from wild oxen in the Near East some 10,500 years ago, according to a new genetic study. Scientists extracted DNA from the bones of domestic cattle found at Iranian archaeological sites. The samples came from the region where archaeologists believe cattle were first domesticated, and from a time not long after farming was invented. The researchers studied how small differences in the DNA of those cattle, as well as living cattle, could have arisen given known differences in population histories. Using computer simulations they found that the DNA variations could only have arisen if a small number of animals, about 80, were domesticated from wild oxen, known as aurochs. The study appears in the current issue of the journal Molecular Biology and Evolution. “This is a surprisingly small number of cattle. We know from archaeological remains that the wild ancestors of modern-day cattle, known as aurochs, were common throughout Asia and Europe, so there would have been plenty of opportunities to capture and domesticate them,” said Mark Thomas, geneticist and an author of the study based at the University College London. “Wild aurochs are very different beasts from modern domestic cattle,” added Joachim Burger, an author of the study based at the University of Mainz, Germany. “They were much bigger than modern cattle, and wouldn’t have had the domestic traits we see today, such as docility. So capturing these animals in the first place would not have been easy, and even if some people did manage to snare them alive, their continued management and breeding would still have presented considerable challenges until they had been bred for smaller size and more docile behavior.” Ruth Bollongino of France’s National Center for Scientific Research and the University of Mainz, Germany, lead author of the study, said a hot climate made it a challenge to get useable DNA samples. “Getting reliable DNA sequences from remains found in cold environments is routine,” she explained. “That is why mammoths were one of the first extinct species to have their DNA read. But getting reliable DNA from bones found in hot regions is much more difficult because temperature is so critical for DNA survival. This meant we had to be extremely careful that we did not end up reading contaminating DNA sequences from living, or only recently dead cattle.” Archaeological studies on the number and size of prehistoric animal bone found that cattle, goats, sheep and pigs were all first domesticated in the Near East. But how many animals were domesticated for any of those species is a much harder question to answer. “In this study genetic analysis allowed us to answer questions that until now archaeologists would not even attempt to address,” said Jean-Denis Vigne a bio-archaeologist at the National Center in France and co-author of the study. “A small number of cattle progenitors is consistent with the restricted area for which archaeologists have evidence for early cattle domestication circa 10,500 years ago. This restricted area could be explained by the fact that cattle breeding, contrary to, for example, goat herding, would have been very difficult for mobile societies, and that only some of them were actually sedentary at that time in the Near East.” scientists find