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Ancient Beachcombers May Have Travelled Slowly
May 12, 2008
New evidence, more questions. That's the thumbnail of the first new data reported in 10 years from Monte Verde, the earliest known human settlement in the Americas. Evidence from the archaeological site in southern Chile confirms Monte Verde is the Americas earliest known settlement and is consistent with the idea that early human migration occurred along the Pacific Coast more than 14,000 years ago, but questions remain about just how rapidly that migration occurred.
"If all the early American groups were following a similar pattern of moving back and forth between inland and coastal areas, then the peopling of the Americas may not have been the blitzkrieg movement to the south that people have presumed, but a much slower and more deliberate process," says Tom Dillehay, professor of anthropology at Vanderbilt University, Nashville, Tenn., who led the study.
The journal Science publishes a report on the findings by Dillehay and team of international scientists in its May 9 issue.
"Monte Verde is an iconic site in New World archaeology and Americanist archaeologists recognize its importance," says John Yellen, program manager at the National Science Foundation, which funded the research. "They also agree that Tom Dillehay has conducted an outstanding program of research there."
Most scholars now accept that people entered North America through the Bering Strait land bridge before 16,000 calendar years ago. It is not known whether people colonized the Americas by moving along the Pacific coast, through interior routes or both.
Researchers envision that coastal migration would have been a rapid process, but seaweed samples and gomphothere meat (meat from an extinct elephant-like animal that was widespread in the Americas 12-1.6 million years ago) found at Monte Verde may be signs of slower migration.
Although the site is located 50 miles from the Pacific coast and 10 miles from an inland marine bay to the south, Dillehay and the research team identified nine species of seaweed and marine algae found in hearths and other areas in the settlement. The samples were directly dated between 14,220 to 13,980 years ago, 1,000 years earlier than other reliably dated human settlements in the Americas and indicate that early immigrants could have moved south along the shoreline exploiting familiar coastal resources to get much of their food.
The researchers also found a number of inland resources, including gomphothere meat. The finding suggests immigrants moved back and forth between the coast and inland areas.
"It takes time to adapt to these inland resources and then come back out to the coast. The other coastal sites that we have found also show inland contacts," says Dillehay.
A wide variety of food was found at the site, including an extinct species of llama, shellfish, vegetables and nuts. The findings make it more difficult to determine the rate of coastal migration in the Americas and the specific path of the immigrants.
"We have no hard evidence that people migrated either rapidly or slowly along the coast," says Dillehay. "Most scholars believe that the first people came via the land bridge but the question is open."
Evidence to support the coastal migration theory is particularly hard to find because sea levels at the time were about 200 feet lower than today. As the sea level rose, it covered most of the early coastal settlements. But the seaweed finding, one of the most significant, verifies the migrants' use of coastal resources, making it a likely path.
"Finding seaweed wasn't a surprise, but finding five new species in the abundance that we found them was a surprise," said Dillehay. "The Monte Verdeans were really like beachcombers. The number and frequency of these items suggests very frequent contact with the coast, as if they had a tradition of exploiting coastal resources."
The National Science Foundation (NSF)
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Wave-induced sediment transport and onshore sandbar migration [An article from: Coastal Engineering]
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This digital document is a journal article from Coastal Engineering, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.
Description: The 25-m onshore migration of a nearshore sandbar observed over a 5-day period near Duck, NC, is simulated with a simplified, computationally efficient, wave-resolving single-phase model. The modeled sediment transport is assumed to occur close to the seabed and to be in phase with the bottom stress. Neglected intergranular stresses and fluid-granular interactions, likely important in concentrated flow, are compensated for with an elevated (relative to that appropriate for a clear fluid) model roughness height...
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Bed load transport under irregular waves plus current from Monte Carlo simulations of parameterized models with application to ripple migration rates observed ... field [An article from: Coastal Engineering]
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This digital document is a journal article from Coastal Engineering, published by Elsevier in 2004. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.
Description: The bed load transport rate under random waves plus current has been predicted for a large range of wave-current conditions. A parameterized model valid for regular waves plus current has been used in Monte Carlo simulations, assuming the wave amplitudes to be Rayleigh distributed. The mean value, standard deviation and numerical estimates of the probability density function of the bed load transport rate are presented for a wide range of wave-current conditions. It appears that overall the effect of the current...
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This digital document is a journal article from Coastal Engineering, published by Elsevier in 2006. The article is delivered in HTML format and is available in your Amazon.com Media Library immediately after purchase. You can view it with any web browser.
Description: In this paper the geometric and migration characteristics of sandwaves generated under the combined effect of waves and currents are described. Description and analysis of the flow structure along the centerline of developed sandwaves are also presented. The velocity distribution along the sandwave is used to explain, in part, the size and shape characteristics of the ripples superimposed upon the sandwaves (as discussed in the companion paper [Catano-Lopera, Y. and Garcia, M.H., in press. Geometry and migration...
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Sun Seeking Britons In Coastal Turkey: A Case Study of Lifestyle Migration on the Verge of the EU
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Coastal Turkey, quite recently emerged as a new destination for Western European migrants who are on the move for more personal, quality of life related motives. These ?sun-seeking patchwork- biography makers" are notably visible - not only in several towns but also on the political agenda of the country which has lately been marked by an ambivalence of its relations with the European Union. Based on a qualitative research carried out during 2006 in Didim, a coastal town in Western Turkey with an established brand name Altinkum in the the mass tourism market, this book provides an account of the experiences of the British migrants and the locals. Exploring the meaning of this migratory phenomenon for the parties involved, it aims at shedding some...
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