Neolithic animal domestication as seen from ancient DNA

In recent years, archaeological, archaeozoological and population genetic studies have increasingly converged on a southwest Asian origin for the four Neolithic farm animals: cattle, sheep, goats, and pigs. The power of ancient DNA studies lies in the possibility of tracking the genetic traces of major demographic processes, such as domestication itself and subsequent migration, at their spatiotemporal sources. In doing so, they are bypassing more recent events, which may have blurred ancient signals until the point of disappearance. Past ancient DNA studies have mostly relied on a single, powerful and – even for degraded ancient samples – easily accessible genetic marker: the maternally inherited mitochondrial DNA (mtDNA). For example, mtDNA studies have allowed for a correlation of genetic diversity patterns with Neolithic expansion routes and to infer ancestral population sizes at the domestication origin for cattle, and to detect evidence for hybridisation between imported domesticated and local wild populations in pigs. However, novel technologies that enable high-throughput sequencing of entire genomes have revolutionised the field of ancient DNA research. The continuously growing field of palaeogenomics is now able to address detailed questions about past population dynamics, including the complex history of population admixture and selection. This article will outline the potential of ancient DNA data gained from traditional and high-throughput sequencing technologies, and how they contribute to present and future domestication research.