Genetic studies shed light on social structure of Catalhoyuk inhabitants

The social structure of the inhabitants of one of the oldest cities in the world, Catalhoyuk in Turkey, was more complex than scientists assumed. Kinship could have a secondary role in it, scientists determined on the basis of DNA tests of the deceased.

The northwest platform of Building 3 showing the multiple burials beneath its floors
[Credit: Catalhoyuk Project]

Catalhoyuk, an archaeological site in central Turkey, was inhabited for almost 1200 years between 7100 and 5950 BC. It is estimated that in the period of the greatest prosperity, the densely built settlement with an area of several dozen hectares had approx. 6,000 residents. An interesting fact is that the dead were buried under the floors of houses.

An international team of geneticists (which includes researchers from Ankara and Stockholm) coordinated by Maciej Chylenski from the Fossil DNA Laboratory at the Adam Mickiewicz University in Poznan decided to study the DNA of some of the human remains discovered in the prehistoric settlement. Researchers focused on the remains of nearly 40 people found under the floors of 4 houses inhabited by approx. 8,500 years ago. In an interview with PAP, Chylenski emphasises that the genetic material is poorly preserved, which is why its examination is not an easy task.

"For now, we know that the dead buried under the same house were not related in the maternal line. For example, in the case of children found under the floors, the women buried next to them were not their mothers. We do not know if they were related in any other way", Chylenski says. He adds that further analysis of data from nuclear genomes is necessary to completely rule out kinship, but these genomes are poorly preserved. The geneticist will make further attempts to obtain nuclear genomes in the near future.

"However, the mitochondrial genomes, in combination with the results obtained by anthropologists working at the site, suggest that the social structure of Catalhoyuk was more complex than one would expect and biological kinship could have a secondary role in it", the scientist says.

A) The location of Catalhoyuk and other sites with complete mitochondrial genomes used as the reference
 for the study: (BNE) Bronze Age Near East, (CBA) Chalcolithic Balkans, (LBC) Late Bronze Age Caucasus,
(LCL) Late Chalcolithic Levant, (MIC) Minoan Create, (NBA) Neolithic Balkans, (NBC) Neolithic to Bronze
Age Caucasus, (NCA) Neolithic Central Anatolia, (NGM) Neolithic Greece and Macedonia, (NME) Neolithic
Middle East, (NMR) Neolithic Marmara Region, (NNL) Natufian and Neolithic Levant. (B) Outline of the
Catalhoyuk East mound with visible excavation areas. (C) Close-up of the excavation area and buildings
targeted for the study with the locations and the obtained mitochondrial haplogroups
of the individuals reported in the paper [Credit: Chylenski et al. 2019]

Thus, as a result of the genome analysis, numerous previous archaeological speculations have been disproved - the inhabitants of one house probably did not belong to one family.

Geneticists also found that in genetic terms, the inhabitants of the prehistoric city were genetically closely related to the peoples of the Sea of Marmara. This area played an important role in the spread of agriculture and animal breeding in Europe, called the Neolithic Revolution.

"The time of the beginning of the Neolithic in both regions and similarities in material culture may indicate that populations from Central Anatolia, or groups closely related to them, participated in the Neolithic Revolution in the Marmara Sea region", Chylenski says.

Catalhoyuk is one of the most famous archaeological sites in the world. It became famous due to the characteristic buildings consisting of houses built of mud brick. Their walls adhered directly to each other, and the entries were at the roof level. The interiors of some of the houses were richly decorated with paintings, among other things. In 2012, it was inscribed as a UNESCO World Heritage Site.

The results of the study were published in the journal Genes.

Author: Szymon Zdzieblowski | Source: PAP - Science in Poland [May 16, 2019]