23 September 2016

RESEARCH - DNA Shows Cats Lived With Vikings and the First Farmers

Humans know very little about the domestication of cats - especially when compared to domestication of dogs.

Some people even question if the independent, often stubborn felines are domesticated at all as they run to do their cat’s bidding.

Scientists debate their domestication because there is so little information, it’s unclear whether a cat’s behaviour and anatomy are clearly distinct from those of wild relatives.

A new study of the DNA of 209 cats found at 30 archaeological sites across Europe, the Middle East and Africa has provided some clues to the domestication and global spread of house cats.

Eva-Maria Geigl, an evolutionary geneticist at the Institut Jacques Monod in Paris, and her team presented the study at the 7th International Symposium on Biomolecular Archaeology in Oxford, UK.

According to the researchers, cats may have lived among ancient farmers, mariners and even Vikings.

Some DNA samples were from up to 15,000 years ago which puts them in the Mesolithic period when humans lived as hunter gatherers - before agriculturalization.

Researchers found:
  • In the Middle East, wild cats of a particular mitochondrial lineage grew with the first farming communities, stretching to the eastern Mediterranean.
  • A mitochondrial lineage common among Egyptian cat mummies from the 4th century BC to the 4th century AD eventually spread to reach Bulgaria, Turkey, and sub-Saharan Africa.
  • The lineage of the Egyptian cat mummies was also found at a Viking site from roughly the 8th – 11th century in northern Germany.

The researchers suggest cats grew in two waves.

The Middle Eastern wild cats were attracted to the grain piles of early farming communities which attracted rodents, and the farmers were happy for the rodent control and may have begun to tame the cats.

Thousands of years later, cats descended from those in Egypt rapidly spread around Africa and Eurasia.

“There are so many interesting observations” in the study, Pontus Skoglund, a population geneticist at Harvard Medical School in Boston, Massachusetts told Nature. “I didn’t even know there were Viking cats.”

Geigl’s study focused on mitochondrial DNA which traces a single maternal lineage.

Skoglund believes that more can be learned if a study was done on nuclear DNA which provides even more information about an individual’s ancestors.

Geigl’s team did look at nuclear DNA - they analyzed nuclear DNA sequences known to give tabby cats striped or blotched coats, and found that the mutation responsible did not appear until the Medieval period.

After such fascinating results from mitochondrial DNA, Geigl hopes to sequence more nuclear DNA from ancient cats. Her biggest challenge is funding for the new study.

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