Thursday, April 05, 2012

Domesticating cattle not as easy as once thought

Past Horizons  

A new genetic study has revealed that all Taurine cattle are descended from as few as 80 animals that were domesticated from wild ox in the Near East.

An international team of scientists from the CNRS and National Museum of Natural History in France, the University of Mainz in Germany, and UCL in the UK were able to conduct the study by first extracting DNA from the bones of domestic cattle excavated from Iranian archaeological sites. These sites date to not long after the invention of farming and are in the region where cattle were first domesticated.

Previous archaeozoological and genetic data had indicated that taurine cattle were first domesticated from local wild ox (aurochs) some 10,500 years ago. However a lack of ancient DNA data from the region of origin, mutation variation rate estimates and limited application of appropriate methodologies resulted in uncertainty on the actual number of animals first domesticated.

The team examined how small differences in the DNA sequences of those ancient cattle, as well as cattle living today, could have arisen given different population histories. Using computer simulations they found that the DNA differences discovered could only happen if a small number of animals, approximately 80, were domesticated from the wild ox.


Thanks to Kate Phizackerley's News From the Valley of the Kings for this link.

Cows are quite possibly the most important domesticated animal in human history, providing vast quantities of meat, dairy products, leather, and let's not forget manure for fertilizer. And yet DNA analysis reveals ancient humans almost didn't succeed in domesticating cows at all.

There are about 1.3 billion cows in the world today. That makes just a bit of a change from 10,500 years ago, when the first population of domesticated cattle was likely just eighty head. That's the new finding from a team of British, French, and German researchers, who extracted DNA from cow bones found at an Iranian archaeological site that dates to not long after the domestication of cows.

They discovered that the differences between these ancient DNA sequences and those of modern cattle were so minute that the only way to explain them would be if the original cattle population was extremely small, with about 80 cattle the most likely number.

Original article in: Molecular Biology and Evolution journal

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