Contact: Jo Kelly
joke...@campuspr.co.uk
University of Leeds
New research forces U-turn in population migration theory
Research led by the University of Leeds has discovered genetic
evidence that overturns existing theories about human migration into
Island Southeast Asia (covering the Philippines, Indonesia and
Malaysian Borneo) - taking the timeline back by nearly 10,000 years.
Prevailing theory suggests that the present-day populations of Island
Southeast Asia (ISEA) originate largely from a Neolithic expansion
from Taiwan driven by rice agriculture about 4,000 years ago - the so-
called "Out of Taiwan" model.
However an international research team, led by the UK’s first
Professor of Archaeogenetics, Martin Richards, has shown that a
substantial fraction of their mitochondrial DNA lineages (inherited
down the female line of descent), have been evolving within ISEA for a
much longer period, possibly since modern humans arrived some 50,000
years ago.
Moreover, the lineage can be shown to have actually expanded in the
opposite direction - into Taiwan - within the last 10,000 years.
Says Professor Richards: “I think the study results are going to be a
big surprise for many archaeologists and linguists on whose studies
conventional migration theories are based. These population expansions
had nothing to do with agriculture, but were most likely to have been
driven by climate change - in particular, global warming and the
resulting sea-level rises at the end of the Ice Age between
15,000-7,000 years ago.”
At this time the ancient continent known as Sundaland – an extension
of the Asian landmass as far as Borneo and Java – was flooded to
create the present-day archipelago.
Although sea-level rise no doubt devastated many communities, it also
opened up a huge amount of new coastal territory for those who
survived(1). The present-day coastline is about twice as great as it
was 15,000 years ago.
“Our genetic evidence suggests that probably from about 12,000 years
ago these people began to recover from the natural catastophes and
expanded greatly in numbers, spreading out in all directions,
including north to Taiwan, west to the Southeast Asian mainland, and
east towards New Guinea. These migrations have not previously been
recognised archaeologically, but we have been able to show that there
is supporting evidence in the archaeological record too.”
###
The interdisciplinary research team comprised colleagues from Leeds,
Oxford, Glasgow, Australia and Taiwan. The study was funded by the
Bradshaw Foundation and the European Union Marie Curie Early Stage
Training program and is published in the current issue of Molecular
Biology and Evolution (MBE).
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