Pages

Friday, October 31, 2025

20,000 year ago date for the peopling of America (Oct. 2025 paper)


A brand new paper published in ScienceAdvances on October 22, 2025 (David B. Madsen et al., Characterizing the American Upper Paleolithic. Sci. Adv.11, eady9545(2025). DOI:10.1126/sciadv.ady9545) compared the stone tool technologies in American and Northeast Asian sites and dated them analyzing their evolution, location and timing to conclude a window for the peopling of America.


The study finds that North American stone tools from sites across the subcontinent dated 13.5 to 20 ky arose from a style of projectile points that seems to have appeared originally in Japan, in Hokkaido some 20,000 years ago. So, they suggest that the North American core-and-blade and bifacial technology has its roots in NE Asia around this time, and was taken there as the first arrivals reached the New World.


The paper characterizes these tools as: "Both the core-and-blade and bifacial techniques were used to support the production of a variety of lanceolate and stemmed projectile points. These are usually small, often less than 5 cm in length but occasionally reach up to ~10 cm long at sites such as Cooper’s Ferry/Nipéhe."


Then, some 13,000 years ago, the Native Americans shifted to more sturdy stone tools, these were the Haskett and Clovis tools, for spears and javelins.


This is a clear indication that Clovis wasn't "First" after all.


The authors find that the dates stands somewhere around 20,000 years ago:


...we suggest that this initial migration occurred sometime about 20,000 years ago. Praetorius et al. (101), in a review of environmental conditions along the Pacific coast of North America, particularly variations in the strength of counterclockwise coastal currents, suggest that the most optimal times for a coastal migration during this period were between ~24,500 and ~22,000 cal yr B.P. and again between ~20,000 and ~19,000 cal yr B.P. Similarly, on the basis of an examination of faunal records from the same southern Alaska and Canadian coastal zone, Steffen (102) concludes that glacial ice cover “probably hindered” migration starting between ~23,300 and ~20,000 cal yr B.P. and lasted until ~18,900 to ~17,700 cal yr B.P. Together, these studies conclude that conditions were optimal for a coastal migration into the Americas sometime about 22,000 years ago, a time estimate compatible with our archeologically based estimate of sometime shortly before ~20,000 cal yr B.P.


The two references cited, Praetorius and Steffen can be found below:


101. S. K. Praetorius, J. R. Alder, A. Condron, A. C. Mix, M. H. Walczak, B. E. Caissie, J. M. Erlandson, Ice and ocean constraints on early human migrations into North America along the Pacific coast. Proc. Nat. Acad. Sci. U.S.A. 120, e2208738120 (2023). Online.
102. M. L. Steffen, New age constraints for human entry into the Americas on the north Pacific coast. Sci. Rep. 14, 4291 (2024). Online.


Slowly but surely, studies are pushing back the date of entry into America. I am an optimist and expect even older dates to be accepted in the next decade (like 30-40,000 years B.P.).


Below is Fig. 9 from this paper, and I quote its caption fully. Surprisingly there were NO STONE TOOLS in Beringia between 15 and 39 ky! probably due to the fact that the sites are underwater, on the now submerged continental shelf.


chart and timeline
Fig. 9. Summary diagram showing the chronological relationships between lithic assemblages in the PSHK, Beringia, and the AUP. Note the complete absence of lithic assemblages dating to between ~30,000 and ~15,000 cal BP in Beringia. Note also that the common features of AUP assemblages appear several thousand years earlier in PSHK stone tool assemblages. Finally, note the chronological relationship between the stemmed and lanceolate points of the AUP, and the appearance of the larger, and more robust lanceolate Haskett and Clovis points characteristic of the later Western Stemmed Tradition and Paleoindian periods. Source and see it online


Patagonian Monsters - Cryptozoology, Myths & legends in Patagonia Copyright 2009-2025by Austin Whittall © 

No comments:

Post a Comment