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Early in the nineteenth century, geologist Charles Lyell reasoned that successively older faunas would contain progressively more extinct species and younger faunas relatively more extant species. The present, with one-hundred percent extant species, was the chronological anchor. In archaeology a similar notion underpins the direct historical approach: Successively older cultures will contain progressively fewer of the cultural traits found in extant cultures and relatively more prehistoric traits. As in Lyell's scheme, the chronological anchor is the present. When A. L. Kroeber invented frequency seriation in the second decade of the twentieth century, he retained the present as a chronological anchor but reasoned that the oldest cultural manifestation would contain the highest percentage of a variant, or what came to be known as a "style," of an ancient trait, and successively younger cultural manifestations would have progressively lower percentages of that variant. The principle of overlapping permitted building sequences of fossils and artifacts, but differences in the units that allowed the chronometers to be operationalized reveal significant epistemological variation in how historical research is undertaken. This variation should be of considerable interest to paleobiologists and archaeologists alike, especially given recent archaeological interest in creating and explaining historical lineages of artifacts.

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American Antiquity






© 2000 Cambridge University Press. Original published version available at

Lyman R.L., O'Brien M.J.. 2000. Chronometers and units in early archaeology and paleontology.Cambridge University Press.

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