June 29, 2007I am not sure if Mr. Wade just has a thing about cats or if he gets a journal of research reports that includes such cat research. No matter, I am enjoying his reports.Study Traces Cat’s Ancestry to Middle East
By NICHOLAS WADE
Some 10,000 years ago, somewhere in the Near East, an audacious wildcat crept into one of the crude villages of early human settlers, the first to domesticate wheat and barley. There she felt safe from her many predators in the region, such as hyenas and larger cats.
The rodents that infested the settlers’ homes and granaries were sufficient prey. Seeing that she was earning her keep, the settlers tolerated her, and their children greeted her kittens with delight.
At least five females of the wildcat subspecies known as Felis silvestris lybica accomplished this delicate transition from forest to village. And from these five matriarchs all the world’s 600 million house cats are descended.
A scientific basis for this scenario has been established by Carlos A. Driscoll of the National Cancer Institute and his colleagues. He spent more than six years collecting species of wildcat in places as far apart as Scotland, Israel, Namibia and Mongolia. He then analyzed the DNA of the wildcats and of many house cats and fancy cats.
Five subspecies of wildcat are distributed across the Old World. They are known as the European wildcat, the Near Eastern wildcat, the Southern African wildcat, the Central Asian wildcat and the Chinese desert cat. Their patterns of DNA fall into five clusters. The DNA of all house cats and fancy cats falls within the Near Eastern wildcat cluster, making clear that this subspecies is their ancestor, Dr. Driscoll and his colleagues said in a report published Thursday on the Web site of the journal Science.
The wildcat DNA closest to that of house cats came from 15 individuals collected in the deserts of Israel, the United Arab Emirates, Bahrain and Saudi Arabia, the researchers say. The house cats in the study fell into five lineages, based on analysis of their mitochondrial DNA, a type that is passed down through the female line. Since the oldest archaeological site with a cat burial is about 9,500 years old, the geneticists suggest that the founders of the five lineages lived around this time and were the first cats to be domesticated.
Wheat, rye and barley had been domesticated in the Near East by 10,000 years ago, so it seems likely that the granaries of early Neolithic villages harbored mice and rats, and that the settlers welcomed the cats’ help in controlling them.
Unlike other domestic animals, which were tamed by people, cats probably domesticated themselves, which could account for the haughty independence of their descendants. “The cats were adapting themselves to a new environment, so the push for domestication came from the cat side, not the human side,” Dr. Driscoll said.
Cats are “indicators of human cultural adolescence,” he remarked, since they entered human experience as people were making the difficult transition from hunting and gathering, their way of life for millions of years, to settled communities.
Until recently the cat was commonly believed to have been domesticated in ancient Egypt, where it was a cult animal. But three years ago a group of French archaeologists led by Jean-Denis Vigne discovered the remains of an 8-month-old cat buried with its human owner at a Neolithic site in Cyprus. The Mediterranean island was settled by farmers from Turkey who brought their domesticated animals with them, presumably including cats, because there is no evidence of native wildcats in Cyprus.
The date of the burial far precedes Egyptian civilization. Together with the new genetic evidence, it places the domestication of the cat in a different context, the beginnings of agriculture in the Near East, and probably in the villages of the Fertile Crescent, the belt of land that stretches up through the countries of the eastern Mediterranean and down through what is now Iraq.
Dr. Stephen O’Brien, an expert on the genetics of the cat family and a co-author of the Science report, described the domestication of the cat as “the beginning of one of the major experiments in biological history” because the number of house cats in the world now exceeds half a billion while most of the 36 other species of cat, and many wildcats, are now threatened with extinction.
So a valuable outcome of the new study is the discovery of genetic markers in the DNA that distinguish native wildcats from the house cats and feral domestic cats with which they often interbreed. In Britain and other countries, true wildcats may be highly protected by law.
David Macdonald of Oxford University, a co-author of the report, has spent 10 years trying to preserve the Scottish wildcat, of which only 400 or so remain. “We can use some of the genetic markers to talk to conservation agencies like the Scottish Natural Heritage,” he said.
If you find this interesting, you will find Nicholas Wade's book Before the Dawn: Recovering the Lost History of Our Ancestors about DNA research into how human beings evolved absolutely fascinating. DNA evidence shows that there were two different wave of human exodus out of Africa, first by Homo Erectus about 1.8 million years ago, becoming Homo Erectus and Neanderthal Man. While these groups were tool using, they did not have full speech of the kind demonstrated by Homo Sapiens. Full speech developed in Africa within the last hundred thousand years, and the first Exodus of true humans from Africa to the rest of the world occurred roughly 50,000 years ago.
DNA analysis suggests that they left Africa by a route from what today is the Horn of Africa and moved into what is today Yemen. The analysis also shows the routes taken by various groups from Africa to Australia, Asia, Europe, and the Americas. Geology and Climatology show what routes they took. Evolution theory suggests that the two evolutionary pressures that caused the differentiation of the races were climatic uncertainty and (the more important one) the standards of beauty each society developed. Both the Asian race and the Caucasian race developed lighter skin because of the need to get more Vitamin D from the shorter periods of sunlight in the far North. Very interestingly, the DNA results tend to agree with the studies of language development over the same periods of time and in the same places.
The book is highly readable and easy to follow, although there is so much in it you will take your time going through it. This is not the early history you may have read before the year 2002 when the human genome was mapped. Suddenly we have entirely new sources of information to compare against anthropology, geology and linguistics among other disciplines, to the real benefit of all the sciences. We also have Nicholas Wade, a writer who can understand how this all fits together and explains it clearly. It's well worth your reading time.
Other suggested books are
- How Brains Think: Evolving Intelligence, Then and Now
by William H. Calvin
and - Guns, Germs, and Steel: The Fates of Human Societies, New Edition
by Jared Diamond. - The Great Transformation: The Beginning of Our Religious Traditions
by Karen Armstrong.
Unfortunately, Cats do not play a prominent role in any of them. If house cats could read, they would demand the attention which everyone and every cat knows they deserve.
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