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June 29th 07, 06:59 AM
Scientists Link Housecats to Wildcat Subspecies

By NICHOLAS WADE

The New York Times
Published: June 28, 2007

Some 10,000 years ago, somewhere in the Near East, an audacious wild
cat 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, and the
rodents that infested the settlers' homes and granaries were
sufficient prey for her.

Seeing 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, scientists have concluded, based on new DNA research. And
from these five matriarchs, all the world's 600 million housecats are
descended.

Carlos A. Driscoll of the National Cancer Institute and colleagues
spent more than six years collecting species of wildcat from Scotland
to Israel. He then analyzed the DNA of the wildcats, of many ordinary
house cats and of the fancy cats that breeders started to develop in
the 19th century.

Five subspecies of wildcat spread 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 5 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 report in a paper published online by Science.

The wildcat DNA closest to that of modern house cats came from 15
individuals collected in the remote 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, which is passed down solely through the
female line. Since the oldest known 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 would have
welcomed the cats' help in controlling them.

Unlike other domestic animals, which were tamed by people, cats
probably domesticated themselves, perhaps accounting 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 eight-month-old cat buried with what was presumably 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, some 9,500 years ago, 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 but stray cats are not.

David Macdonald of Oxford University in England, 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.


http://www.nytimes.com/2007/06/28/science/28cnd-cat.html