In its quest for world domination, the house cat’s journey from feral to human friend had a helping hand from the Vikings.
The finding is published today in a genomic study that traces the geographic dispersal of cats from Neolithic times to the modern day and the process of domestication.
Australian co-author Alison Crowther, from the University of Queensland, said the analysis of DNA from ancient cat remains had revealed “unprecedented insights into the origins and global spread of one of our oldest pets”.
“Before this study, we actually knew very little about the cat domestication and dispersal processes, which is quite surprising given that cats are so popular as pets today,” she said.
Domestic cats are descended from Felis silvestris lybica, the near eastern and north African wildcat, and are now found on all continents, except Antarctica, and in the most remote regions of the world.
However a lack of cat remains in the archaeological record has made it difficult to confirm how Felis silvestris lybica conquered the world, Dr Crowther said.
For the study, researchers analysed DNA samples of hair, teeth, bone and skin from 352 ancient and modern cats from Europe, north and east Africa and south-west Asia.
The specimens spanned across more than 9,000 years of history from the Mesolithic — the period just before the advent of agriculture, when humans lived as hunter-gatherers — to the 20th century.
Co-author Claudio Ottoni, from the University of Leuven, said analysis showed this conquest originated in two waves of dispersal — first from the near east and later from Egypt.
A cat skeleton found with human remains in a 9,500-year-old burial site in Cyprus suggested cats were used by early Neolithic farmers to help control rodents attracted by grain.
The DNA evidence showed this lineage of cat spread to Bulgaria and Romania within 3,000 years.
In the second wave of colonisation several thousand years later, Egyptian cats spread to Europe during the Roman era and became more common than the cats from the near east.
Egyptian cats spread further with the help of Vikings, as shown by cat DNA from the 7th century found in the Viking port in Ralswiek on the Baltic Sea.
Dr Ottoni said their study suggested the “peculiar social and cultural context of the Egyptian society may have facilitated the evolution of a more ‘friendly’ disposition of cats towards humans”.
He said in Egypt cats were at total ease in domestic contexts, as witnessed by Egyptian iconography from more than 3,000 years ago that showed a cat sitting under a chair.
In Medieval times this Egyptian cat spread throughout the Mediterranean along trade routes as the predators were used by mariners to control rodents on board ships.
“Their popularity as a companion animal, together with their role as a pest control agent on ships, might have determined the success of the Egyptian cat in spreading along trade routes, ” Dr Ottoni said.
Despite the “domestication” of cats, Dr Ottoni said they remained “quite independent and even as pets and households’ companion they still keep their innate predatory skills”.
“The modern genome shows the main change in the domestic cat occurred at the level of behavioural features: cats had just to become more friendly, and ‘tolerate’ humans to enter their households and ‘enjoy’ the commodities of life together with humans,” he said.
The researchers were also able to determine when the “tabby cat” first appeared by tracking the gene responsible for the blotched coat.
They showed it became common in the 18th century and it was not until the 19th century that physical traits were selected for the production of fancy breeds.