'Clovis First' - The End

The Late Pleistocene Dispersal of Modern Humans in the Americas

Here's the abstract of the paper mentioned above...

When did humans colonize the Americas? From where did they come and what routes did they take? These questions have gripped scientists for decades, but until recently answers have proven difficult to find.

Current genetic evidence implies dispersal from a single Siberian population toward the Bering Land Bridge no earlier than about 30,000 years ago (and possibly after 22,000 years ago), then migration from Beringia to the Americas sometime after 16,500 years ago. The archaeological records of Siberia and Beringia generally support these findings, as do archaeological sites in North and South America dating to as early as 15,000 years ago. If this is the time of colonization, geological data from western Canada suggest that humans dispersed along the recently deglaciated Pacific coastline.

The paper itself is behind a paywall, but has nevertheless been reported on elsewhere, as we see from Kris Hirst...

I'm not going to argue too strenuously against this--I've thought that was true since the Monte Verde discovery, but the summary in Science is well worth noting, and it will be really interesting to see what the fallout is. Basically, Goebel, Waters and O'Rourke summarize the archaeological and genetic (mtDNA) evidence and conclude that somebody else got here first.

Clovis has been recently redated to 12.0-12.8 kya (kya is archaeo-tech speak for 'thousand years ago'), making it centuries younger than the late-glacial complexes of Alaska.

Fairly secure sites predating Clovis have been found in Chile (Monte Verde, 14.6), Wisconsin (Schaefer and Hebior, 14.8-14.2), Pennsyvlania (Meadowcroft Rockshelter, 15.2-13.4 ka), Florida (Page-Ladson, 14.4 ka), and Oregon (Paisley Cave, 14.1 ka). (The most commonly accepted dates are listed for Monte Verde and Meadowcroft, both of which have older dates associated with them).

Skeletal analysis indicates uncontroversially that fully modern humans populated the Americas, and fully modern humans arrived in Asia no earlier than 40,000 years ago.

Molecular evidence implies a single population left Siberia and headed into the Americas between 30 and 13 ka. Based on these standing assumptions in the record, Goebel and colleagues argue that colonization of the Americas occurred first about 15,000 years ago, immediately after the Pacific coast became deglaciated.

The first Americans were diversified hunter-fishers and used boats, dispersing along the coasts for at least 1,000 years. Clovis, the big-game hunters of mammoths and mastodons, and may be descended from these original Americans, or may represent a second disperal from Beringia.

Although this does indeed appear to sound the death knell for Clovis-first, the date of 15 kya might turn out to be a little conservative - some upper estimates for the earliest peopling of the Americas hover between 40kya, at Valsequillo, and 50kya at the Topper site, but in both cases the jury is still out. Carbon dating at Topper is problematic in that 50,000 years is at the very limit of carbon dating capabilities, and there is an ongoing debate regarding the finds made in the lower levels, whilst at Valsequillo, there doesn't appear to have been much in the way of developments since the initial announcement back in 2005, but as far as I know, neither proposal has yet been disproved. I think both sites open up the possibility of confirming minor settlement events tens of thousands of years ago, with the prospect that other corroborative data will be discovered in the coming years - the site at Walker Hill, in Minnesota also looks promising, and recent reports from Vancouver Island and nearby Orcas Island indicate a possible pre-Clovis presence there also.

The most intriguing site of all is Lake Chapala, which like Valsequillo, is in Mexico, but unlike any other site in the New World, hints at a possible archaic human presence, assuming of course that the material found really is a human brow-ridge. But until further finds are made there, the idea that only Homo sapiens made the journey to the New World will continue to be the accepted paradigm.

In North America, about the first site to really convince archaeologists that pre-Clovis must be a reality was at Meadowcroft Rockshelter, where James Adovasio laboured for many years to convince the sceptical outside world that he and his co-workers had evidence of occupation dating back at least 15kya, and maybe as far back 19kya.

In recognition of his work there, as well as at numerous sites right across the world, the Archaeological Institute of America recently ran an interview with Adovasio, who currently works as Director of the Mercyhurst Archaeological Institute, - here's a brief snippet or two from that interview...


I never anticipated that Meadowcroft would become the epicenter of a three-decade long debate. Because of the extensive amount of funding and support available for this enterprise as well as the high degree of competence of the collaborating scientists, there never really were any insurmountable challenges for excavating and documenting cultural or ecological remains at the site.

Obviously, there was also no problem in publishing the results, particularly since the excavations there were considered, even by critics of the early dates, to represent then, and for that matter now, the state-of-the-art in cave and rock-shelter excavation.

I believe the acceptance of the antiquity of the site is a function not only of the extreme precision used in recovering and contextualizing material from that location but also by the existence now of more than a few other localities which predate the Clovis horizon. The bulk of the evidence now clearly supports an earlier-than-Clovis human presence in the Americas.

Over the years he has worked at a number of sites, addressing many different aspects of life in the Upper Palaeolithic, as we see...

Despite the fact that we have worked off and on at Meadowcroft and the Cross Creek drainage for the past 37 years, I have also been involved in excavations in a wide array of other areas, specifically including 27 of the United States and a series of foreign countries, including Ukraine, the Czech Republic, Israel, and others.

In Ukraine I was involved in the excavation of mammoth bone houses at Mezhirich and in the Czech Republic in the analysis of materials recovered from Pavlovian sites like Dolni Vestonice and Pavlov.

In Israel, I was involved in archaeological and geological data recovery in Ceasarea. At various times I have worked on the analysis of perishable materials from Central and South America as well as Europe and Asia..

...When one is involved in the analysis of basketry and textile materials, objects which are normally associated with the labor of women, it is only natural to have a different perspective of the past than one which is derived from the analysis of stone tools.

I really never decided to re-examine perishable materials specifically from an idea of ascertaining women's roles, since the perishable materials themselves were direct indicators of those roles. I think one of the benefits of examining nondurable technology is the insights that this type of technology provides you not only into the gender roles of the past but also into issues of subsistence and adaptation which are rather radically different than those derived from what one might call an andro-litho-centric view of the past.

And although I don't have access to the paper at top, here's a link to another, published recently at PloSONE, namely...

The Phylogeny of the Four Pan-American MtDNA Haplogroups: Implications for Evolutionary and Disease Studies


see also : Archaeology Magazine : Pre-Clovis Breakthrough by Andrew Curry (April 3rd, 2008)

References to linked paper at top:

The Late Pleistocene Dispersal of Modern Humans in the Americas - Ted Goebel,1* Michael R. Waters,2 Dennis H. O'Rourke3 ¹ Center for the Study of the First Americans, Department of Anthropology, Texas A&M University, 4352 TAMU, College Station, TX 77843–4352, USA.
² Center for the Study of the First Americans, Departments of Anthropology and Geography, Texas A&M University, 4352 TAMU, College Station, TX 77843–4352, USA.
³ Department of Anthropology, University of Utah, Salt Lake City, UT 84122–0060, USA.

image from here