The Science of Coprolite Analysis: The View from Hinds Cave

Dean, G. W.
    Historic Preservation Division, Office of Cultural Affairs (Rm 320), 228 E. Palace Ave., Santa Fe, NM 87501 USA (gdean@oca.state.nm.us)

Nearly a century of human coprolite analysis includes specimens from all over the world and from the dawn of human existence onward. Analytical techniques have evolved with successive generations of researchers willing to explore the ecology of the fecal deposit. Archaeological analyses in the New World, particularly Peru and the North American Southwest, are especially noteworthy due to excellent preservation of sometimes enormous numbers of specimens from single archaeological sites.

My 1978 analysis of 100 specimens from perhaps the first identified prehistoric latrine in North America is a case in point. These specimens represent about 10% of an archaeological deposit with bracketed dates of 5710 +/- 80 and 5590 +/- 80 radiocarbon years before present (uncorrected) from the top and bottom of the deposit, respectively.

The analysis of these 100 specimens provided detailed data on the contents: pollen spectra, plant remains, insect remains, animal bone and fur, and attempts were made to find evidence of intestinal parasites, occult blood residues, viruses, and most recently, sex hormones. An experiment, conducted with volunteers as part of the archaeological analysis, produced 82 modern specimens yielding data on the rate of elimination of specific pollen grains from the human system.

Subsequent coprolite analyses in the American Southwest have focused on fewer specimens from any given time period. Some ideas, such as using pollen concentrations as an indication of recent ingestion, are largely untested for validity. Unwarranted assumptions have also crept into this most anthropological of sciences.

This paper provides new perspectives resulting from my re-examination of my 1978 pollen data. Of particular interest are the results of pollen concentration calculations for both the prehistoric and the modern specimens, and the results of a test to determine the minimum number of coprolites that must be examined to reach a degree of redundancy of data.

The 1978 study remains the most comprehensive analysis of such a large sample of coprolites from a single archaeological site and time period. Yet, this paper shows that there is ever more to learned from these and other coprolite specimens. The application of specialized techniques at the microscope, such as Intensive Systematic Microscopy, to locate and quantify rare pollen types needs to be explored. Parasitological studies of human coprolites will benefit from experimental data to determine the fate of the constituents of human feces ingested by dogs. Easy and valid ways to express the abundance of macroremains in a coprolite are also needed.