Wednesday, April 23, 2008

Climate Change, Sundaland and Human Migration

A March 2008 study provides some of the first genetic evidence of human migration apparently caused by the submergence of Sundaland starting at the beginning of the current warm Holocene period.

MtDNA haplotype E reached Taiwan and the Western Pacific from Sundaland within the last 8,000 years. From a practical standpoint it would be difficult to conceive that the vast sea flooding of the continent would not have spurred extensive demographic movements. Stephen Oppenheimer, whose book "Eden in the East," studied the evidence for such migrations, is one of the contributing authors of this study published in the journal Molecular Biological Evolution.

Paul Kekai Manansala

Mol Biol Evol. 2008 Mar 21

Climate Change and Post-Glacial Human Dispersals in Southeast Asia.

Institute of Integrative and Comparative Biology, Faculty of Biological Sciences, University of Leeds, Leeds, UK.

Modern humans have been living in Island Southeast Asia (ISEA) for at least 50,000 years. Largely because of the influence of linguistic studies, however, which have a shallow time depth, the attention of archaeologists and geneticists has usually been focused on the last 6000 years - in particular, on a proposed Neolithic dispersal from China and Taiwan. Here we use complete mitochondrial DNA (mtDNA) genome sequencing to spotlight some earlier processes that clearly had a major role in the demographic history of the region but have hitherto been unrecognised. We show that haplogroup E, an important component of mtDNA diversity in the region, evolved in situ over the last 35,000 years and expanded dramatically throughout ISEA around the beginning of the Holocene, at the time when the ancient continent of Sundaland was being broken up into the present-day archipelago by rising sea levels. It reached Taiwan and Near Oceania more recently, within the last approximately 8000 years. This suggests that global warming and sea-level rises at the end of the Ice Age, 15,000-7000 years ago, were the main forces shaping modern human diversity in the region.