PhD defense: Hugh McColl

Population History of Southeast Asia – Ancient DNA from the tropics

Supervisor: Prof. Eske Willerslev, UCPH and Univ. Toulouse

Defense Committee Chair: Assoc. Prof. Anders J. Hansen, UCPH

Censor: Prof. Peter Bellwood (ANU, Australia) anf Prof. Qiaomei Fu (Chinese Acadamy of Sciences, China)

While the prehistory of the vast region stretching from Southeast Asia to Australasia is inexhaustible in its complexities, several key phenomena have shaped the broad patterns of human genetic diversity within the region today. On Mainland Southeast Asia, the spread of rice and millet farming from East Asia was instrumental in developing the genetic landscape of present-day peoples of the region. Within Island Southeast Asia, deep sea trenches separating the Sunda and Sahul continental shelves acted as geographical barriers to human migration during the Pleistocene, with the exception of the crossing some 50,000 years ago by the ancestors of the Aboriginal Australians and Papuans. The next clearly documented migration in the region was the Austronesians spreading south from Taiwan into the Philippines and far beyond. The Austronesians appear to be the first peoples to be truly unimpeded by these trenches, becoming ubiquitous across Island Southeast Asia from 4,000 years ago.

This thesis explores ideas presented by archaeologists, paleoanthropologists, linguists and geneticists through the use of ancient DNA (aDNA). The following brief introduction describes recent advances in the aDNA field that have made this research possible, using remains from regions previously thought unsuitable for DNA preservation. The introduction also includes a summary of the archaeological, genetic and linguistic foundations of prehistoric Southeast Asia relevant to this work. Chapter 1 (published) focusses primarily on the transition from hunter-gathering to farming on Mainland and the close association between demographic expansions and the spread of language. Chapter 2 (unpublished manuscript) is a follow-up study investigating in more depth the genetic structure between hunter-gatherer populations, the genetic impact India and China has had on Southeast Asia over the last 4,000 years, as well as migrations between Mainland and Island Southeast Asia. Chapter 3 is a short unpublished manuscript looking at three 500-year-old individuals buried beneath Kota Melaka, Malaysia. The three individuals have extremely diverse genetic origins, a South African, a South Indian and a Malay: most likely royal slaves under the Melaka Sultanate.