Doctoral student Robert D'Anjou and his advisor Raymond Bradley, director of the Climate System Research Center at UMass Amherst, with UMass colleagues Nick Balascio and David Finkelstein, describe their findings in the current online edition of Proceedings of the National Academy of Sciences.
"We are really excited about how well this method worked," D'Anjou says. "Without even knowing it, early settlers were recording their history for us, and in the most unlikely of ways, in their poop. The prehistoric settlers and their livestock pooped and their feces washed into the lake, which over time left a record of trace amounts of specific molecules that are only produced in the intestines of higher mammals. When you find these molecules at certain concentrations and in specific ratios, it provides an unmistakable indicator that people were living in the area."
Bradley adds, "This approach opens the door to other studies, where the presence of humans is uncertain; we believe it has great potential for much wider applications in archaeology."
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