Major transitions in human evolution revisited: a tribute to ancient DNA.

The origin and diversification of modern humans have been characterized by major evolutionary transitions and demographic changes. Patterns of genetic variation within modern populations can help with reconstructing this ∼200 thousand year-long population history. However, by combining this information with genomic data from ancient remains, one can now directly access our evolutionary past and reveal our population history in much greater detail. This review outlines the main recent achievements in ancient DNA research and illustrates how the field recently moved from the polymerase chain reaction (PCR) amplification of short mitochondrial fragments to whole-genome sequencing and thereby revisited our own history. Ancient DNA research has revealed the routes that our ancestors took when colonizing the planet, whom they admixed with, how they domesticated plant and animal species, how they genetically responded to changes in lifestyle, and also, which pathogens decimated their populations. These approaches promise to soon solve many pending controversies about our own origins that are indecipherable from modern patterns of genetic variation alone, and therefore provide an extremely powerful toolkit for a new generation of molecular anthropologists.