Environmental setting of human migrations in the circum-Pacific Region

Oct 10, 2007

A new study by Kevin Pope of Geo Eco Arc Research and John Terrell of The Field Museum adds insight into the migration of anatomically modern humans out of Africa and into Asia less than 100,000 years before present (BP).

The comprehensive review of human genetic, environmental, and archaeological data from the circum-Pacific region supports the hypothesis, originally based largely on genetic evidence, that modern humans migrated into eastern Asia via a southern coastal route.

The expansion of modern human populations into the circum-Pacific region occurred in at least four pulses, in part controlled by climate and sea level changes in the Late Pleistocene and Holocene epochs. The initial “out of Africa” migration was thwarted by dramatic changes in both sea level and climate and extreme drought in the coastal zone.

A period of stable climate and sea level 45,000-40,000 years BP gave rise to the first major pulse of migration, when modern humans spread from India, throughout much of coastal southeast Asia, Australia, and Melanesia, extending northward to eastern Russia and Japan by 37,000 years BP.

The northward push of modern humans along the eastern coast of Asia stalled north of 43° N latitude, probably due to the inability of the populations to adjust to cold waters and tundra/steppe vegetation. The ensuing cold and dry Last Glacial period, ~33,000-16,000 year BP, once again brought dramatic changes in sea level and climate, which caused abandonment of many coastal sites. After 16,000 years BP, climates began to warm, but sea level was still 100 m below modern levels, creating conditions amenable for a second pulse of human migration into North America across an ice-free coastal plain now covered by the Bering Sea.

The stabilization of climate and sea level in the early Holocene (8,000-6,000 years BP) supported the expansion of coastal wetlands, lagoons, and coral reefs, which in turn gave rise to a third pulse of coastal settlement, filling in most of the circum-Pacific region. A slight drop in sea level in the western Pacific in the mid-Holocene (~6,000-4,000 year BP), caused a reduction in productive coastal habitats, leading to a brief disruption in human subsistence along the then densely settled coast.

This disruption may have helped initiate the last major pulse of human migration in the circum-Pacific region, that of the migration to Oceania, which began about 3,500 years BP and culminated in the settlement of Hawaii and Easter Island by 2000-1000 years BP.

Source: Blackwell Publishing Ltd.

Explore further: Researchers collect soil samples from around the globe in effort to conduct fungi survey

add to favorites email to friend print save as pdf

Related Stories

NASA sites across US vulnerable to climate change

Nov 04, 2014

The National Aeronautics and Space Administration has been at the forefront of climate science, launching satellites that take the pulse of Earth's land, oceans and atmospheric systems, gathering data on ...

ESA image: Dead Sea, Middle East

Nov 07, 2014

This image from the Landsat-8 satellite brings us over part of the Middle East, with the Jordan Rift Valley running north to south.

Recommended for you

Parasitic worm genomes: largest-ever dataset released

4 hours ago

The largest collection of helminth genomic data ever assembled has been published in the new, open-access WormBase-ParaSite. Developed jointly by EMBL-EBI and the Wellcome Trust Sanger Institute, this new ...

Male sex organ distinguishes 30 millipede species

4 hours ago

The unique shapes of male sex organs have helped describe thirty new millipede species from the Great Western Woodlands in the Goldfields, the largest area of relatively undisturbed Mediterranean climate ...

How can we avoid kelp beds turning into barren grounds?

8 hours ago

Urchins are marine invertebrates that mould the biological richness of marine grounds. However, an excessive proliferation of urchins may also have severe ecological consequences on marine grounds as they ...

User comments : 0

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.