Father of the study of human coprolites
Dr. Eric Callen was the founder and developer of human coprolite analysis. Up until the mid 60's, human coprolites were thought to be worthless and were usually discarded. Dr. Callen changed all that, but it wasn't easy.
A coprolite is a dried or fossilized piece of animal or human excrement. Dried human coprolites, typically less than 10,000 years old, can be returned to their original texture, odour, and "freshness" by a technique developed by Dr. Callen in 1955. Basically, he soaked the coprolite for 48 hours in a 0.5% solution of trisodium phosphate.
Dr. Callen's laboratory was in MacDonald College at McGill University in Montreal. The lab was small, not much bigger than a walk-in closet, and must have smelled like a sewer because of all the reconstituted feces that he used in his research.
Perhaps because of the subject matter, most scientists at the time thought that coprolite research was not useful, and Dr. Callen endured some ridicule and derision. However, he persevered, and today coprolite research is a respectable and valuable pursuit.
Dr. Callen started his career as a botanist, receiving his doctorate from the University of Edinburgh then getting a job as a professor of plant pathology at McGill University in Montreal. While searching (unsuccessfully) for ancient maize pathogens in human coprolites that were thousands of years old, he discovered a wealth of other information in his samples, including what the person ate and how healthy he or she was. He soon switched his area of research from botany to archeology, and studied coprolites exclusively.
Today, human DNA can be extracted from coprolites, and can give a picture of what people were like and what life was like up to 90,000 years ago. Scientists can even tell when our ancestors began to speak by looking for the FOXP2 gene in the DNA. When the presence of the FOXP2 gene is detected, it means that the person was capable of the jaw movements required for speech.
Dr. Callen died in 1970 while on a field trip to Peru. He was studying coprolites at the Pikimachay archaeological site, one of the oldest locations in South America with evidence of human habitation. He suffered a heart attack while working alone in his lab, and is buried nearby in Ayacucho.
Author: Jeff Schering
Bryant, V.M., & Dean, G.W. (2006). Archaeological coprolite science: The legacy of Eric O. Callen (1912–1970). PALALEO: Palaeogeography, Palaeoclimatology, Palaeoecology, 237, 51-66
Photo: Dr. Vaughn M. Bryant