The largest-ever pedigree constructed from ancient DNA has been pieced together, painting a picture of the lives and relationships of humans who lived 6,700 years ago. The Neolithic marked some big changes for humankind as farming took over from hunter-gathering, enabling our species to develop new social customs and a more sophisticated mating game. Keeping Up With The Kardashians is tired, but Nosing Into The Neolithic is wired.
The emergence of farming brought with it wealth and social hierarchy as groups of humans spread out across western Europe and established small settlements, within which unique cultures began to emerge. Funerary practices changed in ways we’ve found preserved in archaeology, and the particularly informative site of Gurgy ‘Les Noisats’ sits in the Paris Basin region of France.
The cemetery was the source of a glut of ancient DNA used in a recent study to sample individuals and establish two massive family trees, painting an unprecedented picture of love, life, and relationships. One of the trees connects 64 individuals over seven generations, making it the largest pedigree built from ancient DNA to date.
If you’re thinking pedigree is for dogs, you’re right, but it’s also the name given to the record of descent of any animal, including humans – we just tend to call them family trees instead. The study was also able to piece together a second, more modest pedigree, connecting 12 individuals spanning five generations.
Scientists were able to do this by analyzing their genomes, as well as looking for strontium isotope ratio values, mitochondrial DNA data (which typically comes from maternal lineages), Y-chromosome data, age-at-death, and genetic sex. It confirmed the researchers' suspicions that grave sites at the well-organized cemetery at Les Noisats hadn’t been assigned randomly, as there was evidence to suggest the deceased were buried close to relatives.
“Since the beginning of the excavation, we found evidence of a complete control of the funerary space and only very few overlapping burials, which felt like the site was managed by a group of closely related individuals, or at least by people who knew who was buried where”, said Stéphane Rottier from the University of Bordeaux, the archaeo-anthropologist who excavated the site between 2004 and 2007, in a statement.
A "founding father" of the cemetery was identified as the VIP who sat at the top of the largest family tree, and who was found buried next to a female from whom the team were unable to get genetic data. He was evidently of great importance, because the way in which his bones had been buried indicated he’d died somewhere else, been buried and exhumed to be buried again alongside the female.
This male represented the beginning of a strong paternal line, but on the females’ side it was a very different story. The maternal (mitochondrial) lineages and stable isotopes indicated most of the women were from elsewhere geographically, suggesting this was a patrilocal society where males stayed in their homeland but had offspring with females from outside of Gurgy.
Meanwhile, females were sent away, and those joining the community came from a mixture of places rather than just one, meaning the dating scene 6,700 years ago was fluid and widespread as individuals “exchanged” between settlements. Not only would it have made for great TV, but it’s a boon for genetic diversity, too.
These early farmers were also apparently monogamous, as evidenced by the lack of half-siblings which generally rules out polygamy or serial monogamy (having one relationship after another). It seems they liked big families, but they experienced a lot of loss.
“We observe a large number of full siblings who have reached reproductive age,” said first author Maïté Rivollat. “Combined with the expected equal number of females and significant number of deceased infants, this indicates large family sizes, a high fertility rate and generally stable conditions of health and nutrition, which is quite striking for such ancient times.”
The research demonstrates the potential funerary sites like that at Les Noisats hold in opening up a window into our species’ past, meaning we can witness the drama unfold among societies that fell thousands of years ago.
“Only with the major advances in our field in very recent years and the full integration of context data it was possible to carry out such an extraordinary study,” concluded Wolfgang Haak of the Max Planck Institute for Evolutionary Anthropology, senior author of the study. “It is a dream come true for every anthropologist and archaeologist and opens up a new avenue for the study of the ancient human past.”
The study is published in Nature.