No Evidence for Clovis Comet Catastrophe, Archaeologists Say
ScienceDaily (Oct. 1, 2010) — New research challenges the controversial theory that an ancient comet impact devastated the Clovis people, one of the earliest known cultures to inhabit North America.
These are Clovis Points. (Credit: David Meltzer)
Writing in the October issue ofCurrent Anthropology, archaeologists Vance Holliday (University of Arizona) and David Meltzer (Southern Methodist University) argue that there is nothing in the archaeological record to suggest an abrupt collapse of Clovis populations. "Whether or not the proposed extraterrestrial impact occurred is a matter for empirical testing in the geological record," the researchers write. "Insofar as concerns the archaeological record, an extraterrestrial impact is an unnecessary solution for an archaeological problem that does not exist."
The comet theory first emerged in 2007 when a team of scientists announced evidence of a large extraterrestrial impact that occurred about 12,900 years ago. The impact was said to have caused a sudden cooling of the North American climate, killing off mammoths and other megafauna. It could also explain the apparent disappearance of the Clovis people, whose characteristic spear points vanish from the archaeological record shortly after the supposed impact.
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Current Anthropology, 51:575–607, October 2010
© 2010 by The Wenner-Gren Foundation for Anthropological Research. All rights reserved.
0011-3204/2010/5105-0002$10.00
DOI: 10.1086/656015
The 12.9-ka ET Impact Hypothesis and North American Paleoindians
Vance T. Holliday and
David J. Meltzer
Vance T. Holliday is a Professor in the School of Anthropology and Department of Geosciences at the University of Arizona (Tucson, Arizona 85721, U.S.A. [vthollid@email.arizona.edu]). David J. Meltzer is Henderson-Morrison Professor of Prehistory in the Department of Anthropology of Southern Methodist University (Dallas, Texas 75275, U.S.A.).
A hypothesized extraterrestrial impact in North America at 12,900 calendar years BP (12.9 ka) has been proposed as the cause of Younger Dryas climate changes, terminal Pleistocene mammalian extinctions, and a supposed “termination” of the Clovis archaeological culture. In regard to the latter, however, an examination of archaeological, geochronological, and stratigraphic evidence fails to provide evidence of a demographic collapse of post-Clovis human populations, especially where the Clovis and post-Clovis site records are reasonably well constrained chronologically. Although few Clovis sites contain evidence of an immediate post-Clovis occupation, interpreting that absence as population collapse is problematic because the great majority of Paleoindian sites also lack immediately succeeding occupations. Where multiple occupations do occur, stratigraphic hiatuses between them are readily explained by geomorphic processes. Furthermore, calibrated radiocarbon ages demonstrate continuous occupation across the time of the purported “Younger Dryas event.” And, finally, the relatively few sites purported to provide direct evidence of the 12.9-ka impact are not well constrained to that time. Whether or not the proposed extraterrestrial impact occurred is matter for empirical testing in the geological record. Insofar as concerns the archaeological record, an extraterrestrial impact is an unnecessary solution for an archaeological problem that does not exist.
This paper was submitted 22 IV 09 and accepted 05 XI 09.
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