A new study of the remains of 38 people in a mass grave from 6200 years ago in Croatia provides evidence of the mass execution of the all or most of the residents of a small copper age farming villages who were predominantly descended from Anatolian Neolithic farmers.
We don't know why it happened, but the fact that it did belies the myth that early farming civilizations were peaceful utopias.
Mario Novak and his colleagues have just published a paper entitled: Genome-wide analysis of nearly all the victims of a 6200 year old massacre. They sequenced the genome of 38 of the 41 individuals found in a mass grave 2m in diameter and 1m deep in Potočani, Croatia.
. . .Radiocarbon dating measurements showed that these skeletons date from 4200 BC. JC. corresponding to the Eneolithic (copper age) culture of Lasinja. Anthropological analyzes have shown that thirteen of these individuals (six children, three men and four women) presented with peri-mortem cranial injuries located on the side or back of the head which suggest a single summary execution event.The genetic results indicate that all of these individuals show a very homogeneous ancestry.
. . .
On average, these individuals have 91% of farming ancestry from Anatolia and 9% of hunter-gatherer ancestry from the west. They have no ancestry at all from the pastoralists of the steppes. . . . These results are confirmed by the analysis of the haplogroups of the Y chromosome: G2, I2 and C-V20, and in particular the absence of the haplogroups R1a and R1b-M269. There are in particular six different paternal lineages. In addition, analysis of mitochondrial haplogroups identifies 30 different haplotypes suggesting a large community. . . . only eleven individuals present close relationships (up to the third degree), thus forming 4 families:* a man, his two daughters and his nephew* two sisters with a third cousin* A father and his son* a boy with his paternal aunt (or his half-sister)This group of people does not therefore correspond to a single extended family because 70% of them have no family relationship. In addition, among all the individuals there are 20 female and 18 male. This massacre therefore does not correspond to the result of a battle but rather to the extermination of a village community made up of many different families.Analysis of the homozygosity segments indicates that there is very little inbreeding among these individuals.