All modern domesticated cows – the same cud-chewing, lumbering bovines that stare blankly while your kids gawk at them – are descended from a single herd of wild ox which lived 10,500 years ago.
That’s the conclusion derived from a genetic study of cattle conducted by a team of geneticists from the National Museum of Natural History in France, the University of Mainz in Germany and University College London.
The team excavated the bones of domestic cattle on archaeological sites in Iran, and then compared those to modern cows. They looked at how differences in DNA sequences could have arisen under different population history scenarios, modeled in computer simulations, according to Wired magazine.
“The team found that the differences that show up between the two populations could only have arisen if a relatively small number of animals – approximately 80 – had been domesticated from a now-extinct species of wild ox, known as aurochs, which roamed across Europe and Asia,” the publication reported.
From that herd there are today an estimated 1.4 billion cattle worldwide,
It wasn’t easy retrieving DNA from the bones excavated in Iran, according to Ruth Bollongino, the lead author of the study.
“Getting reliable DNA sequences from remains found in cold environments is routine,” she said. “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,” Bollongino added. “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.”
The research has implications for the study of the history of domestication, according to Wired.
“This is a surprisingly small number of cattle. We know from archaeological remains that the wild ancestors of modern-day cattle were common throughout Asia and Europe, so there would have been plenty of opportunities to capture and domesticate them,” said Mark Thomas, a geneticist and an author of the study.
(HT: A Blog About History.)