- Calico Early Man Site
s). The general scientific consensus is that the stones are geofacts. [See Haynes, as one example. Published studies in peer-reviewed journals consistently support the "geofact" explanation.]
Artifacts or Geofacts?
Up to 60,000 possible
stone toolshave been found at Calico. Due to their shape and size, it has been hypothesized by several archaeologists that these objects are artifacts, that is, that they were shaped by human actions. If confirmed, dates for these objects would indicate human presence at Calico far earlier than any other site in the Americas, 50,000 to 200,000 years BP. These dates are based on the age of the sediments containing the stones, which were most recently dated by thermoluminescenceat 135,000 years BP, [Debenham.] and by uranium/ thoriumanalysis at 200,000 years BP. [Bischoff.]
However, in 1979, James G. Duvall and William Thomas Venner published a statistical analysis of the stone objects, stating that they were "not modified by man but, rather, were form selected by the archaeologists. Form selection . . . is the selection of naturally fractured lithics that resemble man-made tools and therefore create a biased sample of
lithics from the total population of naturally fractured lithics at that site". [Duvall and Venner.]
This was followed in 1982 by Louis Payen's analysis of the stone objects against the Barnes platform angle method. [Payen] The Barnes test had been developed to test Paleolithic tools, examining the angle of facture to distinguish a human-chipped stone artifact against those made by nature. Payen concluded that the stone objects were geofacts.
Both the Duvall/Venner and the Payen papers have been criticized on a number of levels, and analyses supporting the pro-artifact argument have been published. [Patterson, et al.] However, the present consensus, by no means unanimous, is that there is no evidence of human activity at the Calico Early Man site. This consensus developed based on a number of factors, including:
:*The lack of other evidence of human activity (e.g. human or animal remains, or non-tool artifacts).:*The deep antiquity of the site (the next oldest date for human artifacts in the Americas is 30,000 BP, and that date itself is controversial).:*The sheer number of possible tools, up to 60,000 by one account. [AmericanWest's Calico Site Update] :*The research by Duvall/Venner, Payen, and others providing possible natural explanations for the stone objects.
History of Excavations
Louis Leakey, while at the British Museum of Natural Historyin London, received a visit from Ruth DeEtte Simpson, an archaeologist from California. Simpson had acquired what looked like ancient scrapers from a site in the Calico Hills and showed it to Leakey.
Leakey viewed it as important to study the Calico Hill site,Morell, pp. 266-267.] , as he was convinced that the number and distribution of native languages in the Americas required more time than 12,000 years to evolve and acquire their current distribution. [Calico Site Update.] The opportunity to test this theory came four years later in 1963, when Leakey obtained funds from the
National Geographic Societyand commenced archaeological excavations with Simpson.
Mary Leakeydid not share his visionary views. She regarded Louis as often slipping into incompetence and often publicised that opinion. ] Louis Leakey continued to visit the site several times a year and was connected with the project until his death in 1972. The site was taken over by California's Bureau of Land Managementand was opened to the public. It presently offers a visitor center, gift shop, and guided walking tour.
* Bischoff, J.L., R.J. Shlemon, T.L. Ku, R.D. Simpson, R.J. Rosenbauer, & F.E. Budinger, Jr., "1981 Uranium-series and Soils-geomorphic Dating of the Calico Archaeological Site, California", "Geology" V9 (12), pp. 576-582.
* Budinger Jr., Fred E., Oberlander, Theodore [http://calicodig.com/image/tid/15/page/1 Calicodig.com] "This web site describes and analyzes the Calico Archaeological Site and the Calico Lithic Industry". With many stone object photos.
* Debenham, N., (1998) Thermoluminescence Dating of Sediment from the Calico Site (California) (CAL1), "Quaternary TL Surveys", Nottingham, United Kingdom, 1998.
* Duvall, James G., and Venner, William Thomas, “A Statistical Analysis of the Lithics from the Calico Site (SBCM 1500A), California”, "Journal of Field Archaeology", Winter 1979: Vol. 6, No. 4, pp. 455-462.
*Haynes, Vance (1973) "The Calico Site: Artifacts or Geofacts?", "Science", vol. 181, no. 4097, July 27, 1973, pp. 305-310.
*Morell, Virginia (1995) "Ancestral Passions: The Leakey Family and the Quest for Humankind's Beginnings", Simon & Schuster, pp. 266-267.
* Payen, L., “Artifacts or geofacts at Calico: Application of the Barnes test,” in "Peopling of the New World", Ericson J., Taylor, R., and Berger, R., eds. Los Altos, California: Ballena Press, 1982, pp. 193–201.
*Patterson, Leland W.; Hoffman, Louis V.; Higginbotham, Rose Marie; Simpson, Ruth D. (1987) " [http://links.jstor.org/sici?sici=0093-4690%28198721%2914%3A1%3C91%3AAOLFAT%3E2.0.CO%3B2-Y&size=LARGE Analysis of Lithic Flakes at the Calico Site, California] ", in "Journal of Field Archaeology", Vol. 14, No. 1 (Spring, 1987), pp. 91-106.
* [http://www.americanwest.com/namarch/calico99.htm AmericanWest's North American Archaeology Section, Calico Site Update.] ". . .over 60,000 tools and flakes have been collected".
* [http://www.blm.gov/ca/st/en/fo/barstow/calico.html Official State of California Calico website]
* [http://www.calicodig.org Calico Archaelogical Site] A site detailing the history/controversy of the site, as well as a gallery of artifacts/geofacts and surrounding areas
* [http://cayman.globat.com/%7Ebandstexas.com/afw97.jpgDetail of an artifact/geofact]
* [http://cayman.globat.com/%7Ebandstexas.com/afw98.jpgDetail of another artifact/geofact]
* [http://cayman.globat.com/%7Ebandstexas.com/afw99.jpgDetail of a third artifact/geofact]
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