Fig. 5

Paleogenomics from ancestral genome reconstruction and aDNA recovery. Paleogenomics encompasses a synchronic approach (top), involving the reconstruction of ancestral genomes of several million years old (macro-evolution) from comparisons of modern genome sequences, and an allochronic approach (bottom), involving the recovery and analysis of ancient DNA from archaeobotanical remains of several hundreds or thousands of years old (micro-evolution). Both approaches are complementary in unveiling the impact of past evolutionary processes (million-years-old genomic rearrangements such as duplications and inversions, illustrated with colored blocks) on the diversity of the modern germplasm (thousand-years-old mutations illustrated with red and green vertical bars, the latter representing mutations that have been lost during domestication and/or the adaptation of modern species). Comparison of DNA from modern and ancient diploid (2X), tetraploid (4X), and hexaploid (6X) species offers the opportunity to investigate the genomic drivers (duplication, inversion, deletion, fusion, fission, mutation…) of plant evolution and adaptation to environmental constraints, as exemplified by wheat (bottom). Excavation and photo A.-M. et P. Pétrequin (CRAVA, CNRS) from Clairvaux-les-Lacs (Jura), CL VII, IVth Millennium BC