According to a new analysis of modern and ancient cat DNA, today’s domestic cat is a descendant of both the Near Eastern and Egyptian populations of the wildcat subspecies Felis silvestris lybica, which was domesticated several times in different locations around the world, with two major waves of domestication. The findings were published in the journal Nature Ecology & Evolution.

The wildcat (Felis silvestris) is distributed all over the Old World. Scientists distinguish five wild, geographically partitioned subspecies: Felis silvestris silvestris, Felis silvestris lybica, Felis silvestris ornata, Felis silvestris cafra and Felis silvestris bieti.

Modern genetic data analyses revealed that only one of them, Felis silvestris lybica, was ultimately domesticated.

“Cats were domesticated some 10,000 years ago by the first farmers in the Near East,” said study co-authors Dr. Eva-Maria Geigl and Thierry Grange, from CNRS and the University Paris Diderot.

“They naturally approached human communities because of mutual interests: they were attracted to villages because of the large numbers of rodents themselves enticed by the grain stores of barley and wheat.”

“This development could have only been beneficial for humans: not only did they rid themselves of rats, but also of snakes and other venomous species that also figured on the menu of Felis silvestris lybica.”

Historical and archaeological records have long given credence to this hypothesis of increasing proximity, and potentially more, between cats and humans since the dawn of agriculture.

“The skeleton of a cat was found in Cyprus in the tomb of a child dating from 7500 BC,” the researchers said.

“A tomb containing nothing but the bones of several unrelated cats was discovered in an Egyptian cemetery dating to around 4500 BC. Once it had been deified in Egyptian images as a helper of the Sun King, Ra, the feline was depicted in hunting scenes from the second millennium BC, before appearing in domestic images, under the seat of the man or woman of the house, even sometimes with a collar.”

Genetic studies conducted in modern cats confirm the genetic proximity between today’s domestic animals and Felis silvestris lybica, but the exact mechanism by which cats spread remained shrouded in mystery.

In order to trace the origins of the domestic cat, the authors examined DNA of 230 ancient and modern cats from Europe, north and east Africa, and southwest Asia, spanning around 9,000 years, from the Mesolithic period to the twentieth century CE.

“We have specimens of European cats that lived 9,000 years ago, Balkan cats from 6,000 years ago, and cats living in Anatolia from between 6,000 years ago and the end of the Ottoman Empire,” the scientists said.

“We also analyzed dozens of mummified cats from Egypt during the Ptolemaic era (from the third to the first century BC). Yet only six of these mummies yielded results. The DNA of the others was too greatly deteriorated due to poor storage conditions in these hot, dry regions.”

According to the researchers, Felis silvestris lybica is indeed the ancestor of today’s domestic cats.

However, to their great surprise, they discovered not one but two waves of domestication.

The first major event was probably in the Fertile Crescent about 7,500 years ago, from wildcats originating in Anatolia.

“Cats can then be seen moving with human populations as early as 5,000 to 6,000 years ago, as farmers spread from the Near East into Europe, and also with seafaring communities,” the authors said.

“We see the spread throughout the entire continent of the genetic signature of the Anatolian variant of lybica.”

“Cats appear to have traveled along maritime trade routes, as well as with military expeditions, which is also supported by historical evidence.”

“In medieval times it was compulsory for seafarers to have cats onboard, to combat the rats and house mice that were a frequent pest on ships.”

The second major wave of domestication occurred in the Greek and Roman periods, when a fad for Egyptian cats led to a movement of domestic cats descended from North African Felis silvestris lybica to Europe.

“At this point we begin to see a real craze for Egyptian cats, the local variant of lybica, which was in fact mentioned in the writings of the Greek historian Herodotus (fifth century BC),” the scientists said.

“The fad for Egyptian cats very quickly spread through the ancient Greek and Roman world, and even much further afield, since cats were found in Viking ports established on the Baltic Sea between 500 and 800 CE.”

The team also analyzed one of the rare genetic markers of domestication in cats: the coloring of their fur.

“The gene coding for spots and mottling is found only in domestic cats, while the fur of wildcats is always striped,” the authors said.

“And here we stumbled on a surprise: spots only began to appear under the Ottoman Empire, between 500 and 1300 CE, becoming more common after 1300 both in the Ottoman Empire and in Europe.”

“This is a very late development in relation to other species. But while this phenomenon constitutes irrefutable evidence of selection by humans, it does not in any way mark the start of companionship between cats and humans, which goes back much further.”

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Claudio Ottoni et al. 2017. The palaeogenetics of cat dispersal in the ancient world. Nature Ecology & Evolution 1, article number: 0139; doi: 10.1038/s41559-017-0139