Torun (dpa) - The ancestors of today's domestic cats were not as closely tied to humans as other pets. This is indicated by the study of 4300 to 6200 year old cat fossils that were found in southern Poland.

The cats from the Middle East presumably followed agricultural people, but they also ate in the wild, as researchers led by Magdalena Krajcarz from the Nicolaus Copernicus University in Torun (Poland) wrote in the journal Proceedings of the National Academy of Sciences »(PNAS) report.

"Even modern domestic cats live somewhere along a continuum from close relationships with humans to wild animals," the scientists explain. They tried to find out how this special position of the domestic cat among the pets came about. According to the current state of research, all domestic cats (Felis silvestris catus) come from the African wildcat (Felis silvestris lybica) - also known as the fallow cat. The two subspecies can hardly be distinguished from one another on the basis of genetic analyzes. Another subspecies, the European wildcat (Felis silvestris silvestris), can be differentiated.

Krajcarz and colleagues found enough intact bone collagen in the remains of six fallow cats in southern Poland to draw conclusions about their diet. To do this, they examined the amount of two stable isotopes: nitrogen-15 is increasingly incorporated into the protein collagen by the body if the food comes from fields that have been fertilized with animal manure. Carbon-13 is found more frequently in collagen, the more C4 plants (especially cereals and other useful plants) the living being has consumed in the last months and years before his death.

The researchers compared the isotopes of cats with those from the remains of humans, pets and wild animals from the time between 4300 and 6200 years ago. They also used domestic cat fossils from the Roman period in Poland. The late Neolithic cats therefore differed significantly in terms of the isotope composition (and consequently in terms of nutrition) from contemporary humans and dogs as well as from strongly human-bound cats from the Roman period.

The nitrogen-15 and carbon-13 values ​​of the six fallow cats were significantly lower, as the study says. This suggests that they ate less mice and other animals that had mainly fed on food from fertilized fields and C4 plants. Instead, they probably hunted animals primarily in the wild, like the European wildcats. According to the researchers, the Neolithic cats were culture followers who found quick prey near the camps of people rather than well-integrated pets.

"The ancestors of the cat were unique among domesticated wild animals due to their solitary, territorial behavior," write the scientists. How close the relationship between the house cat ancestors of the late Neolithic age and the people who once lived in today's Poland was still open.

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