Periodic Reporting for period 1 - CODEV (Co-diversification and co-evolution of human populations and cereals in Africa)
Período documentado: 2019-08-01 hasta 2021-07-31
Agriculture boosted demographic growth and long-distance migrations that greatly shaped the make up of human populations. New environments and lifestyles have resulted in important local adaptations in our specie, e.g. to pathogens, climate or dietary regimes. Likewise, following human movements, many domesticated plants dispersed and experienced local diversification (e.g. shapes, color, taste and usages) to adapt to new physical environments and human preferences.
Despite the connection between human Neolithic transitions and crop domestication, the genetic consequences of these processes are usually addressed separately in humans and plants. The main aim of this project is to jointly analyze the genetic structure of human populations and their domesticated crops to better understand how the common history of migration and expansion of humans and plants shaped the genetic make-up of each species. This project leverages the information on the species past history stored in the genomes, using population genetics approaches and complementary geographical, environmental and ethno-linguistic information. We focus on Africa, where agriculture transitions are still poorly characterized and show distinctive features from other continents, since plant cultivation started late, in multiple areas and spread more slowly and patchily than elsewhere.
Analyses of adaptive diversity at candidate genes showed little evidence of local adaptation in human populations so far, suggesting that the differences observed among populations were mostly driven by the genetic drift associated with specific demographic histories. Candidate functional genes in cereals have been identified, thanks also to the study performed on sorghum in the context of a different research project (Burgarella et. al. 2021 Front. Plant Sci. doi:10.3389/fpls.2021.666075). The analysis of their variability in association with environmental information and the comparison with patterns of human diversity will help identify the main evolutionary processes at play.
Within the framework of this project, scientific and academic collaborations have been initiated and strengthened within the European and African research space. Postgraduate teaching material was developed for courses imparted in Sweden and France. Outreach activities for the general public included contributions to three science festivals and focused on the evolutionary and societal impact of domestication and the contribution of archaeogenetics to reconstruct our history. These activities were diffused in different languages (English, Swedish, Spanish and Italian), and an original video has been created and is available online (https://youtu.be/iSY5_1gzFKc).