In the research project NeoGenHeritage we studied the Neolithic transition in Southern Europe, particularly in the Iberian Peninsula (IP). The Neolithic transition was the most global and revolutionary event in human prehistory, both at the cultural and demographic level, with populations shifting from a subsistence mostly depending on nomadic hunting and gathering to settled communities based on farming. The first archaeological evidence of Neolithic farming is in the Near East around 12000 years before present (yBP) and by 5000 yBP agriculture had spread all over Europe, replacing the Mesolithic lifestyle. Whether this major change was mediated by the diffusion of people or ideas, is a hotly debated question in archaeology, anthropology and population genetics.
In recent years, ancient DNA (aDNA) studies have strongly contributed to shed light on this question by directly describing genetic diversity in past human populations. Thanks to the application of cutting edge technologies such as NGS (next generation sequencing) and DNA hybridization capture, the recovery of whole nuclear genomes from ancient remains has became feasible. The number of ancient human individuals analysed at the nuclear DNA level has grown from a few tens to several hundreds in just the last two years.
However, there are still several problems in paleogenome studies. They are related with the paucity of data from some geographic regions and/or to the low quality/coverage of the genome data available. Also, aDNA studies are now moving from analysing individual mitogenomes and partial nuclear sequences, to the analysis of complete genomes at the population scale. This implies a radical increase in complexity, along with the challenge of incorporating the peculiarities of aDNA (molecular damage, temporal dimension, etc) into the statistical framework of population-genomic analyses.
In our MSCA we have worked to improve the standards in aDNA studies by generating high quality ancient genome data and exploiting the information contained in them by advanced biostatistical inferential methods. We have combined these laboratory and computational approaches to:
- Generate whole nuclear genomes from prehistoric samples in the Iberian Peninsula, covering the time interval between the Mesolithic and Bronze Age. Having been the last region of Europe reached by the Neolithic diffusion, the IP offers a particularly complex (and challenging) opportunity for understanding the relative role of migration and cultural changes at the onset of the Neolithic.
- Test hypotheses about the changes in the genetic landscape of the Iberian populations over time.
- Investigate the age of genetic variants, which have been proposed as target of recent selective events in human evolution.
By the achivement of this research objectives, our MSCA is contributing to a better understanding of human demographic dynamics in southern Europe and of the impact of cultural changes in recent human evolution. A deeper understanding of the origins and evolution of human diversity in Europe is fundamental for designing immigration policies, and for dismissing racist or xenophobic ideas which are on the rise in the public debate. Furthermore, the data that have been generated and the training followed by the researcher, will contribute to reinforce the world leading role of Europe in aDNA research.