New research presented in the open access peer reviewed journal Public Library of Science on December 12, 2012, is the first to examine the evolution of human gut microbes directly from the archeological evidence.
The researchers examined 1400 to 8000 year old fecal samples preserved at three archaeological sites: natural mummies from Caserones in northern Chile, and samples from Hinds Cave in the southern U. S. and Rio Zape in northern Mexico. They also analyzed the gut microbes of Otzi the Iceman and a soldier frozen on a glacier for nearly a century.
The ancient microbiota were compared with the microbes in present day soil and compost, as well as the microbes present in mouths, gut and skin of people in rural African communities and cosmopolitan United States adults
The ancients microbial protectors (now extinct) resembled present day compost bacteria and could be comparable to the mouth and gut microbes found in present rural populations in Africa.
The authors conclude that the development of an easier life has left humans more susceptible to disease but the fact that large numbers of the people of the Earth still live in environments that promote a more protective defense system to disease. This bodes well for the future existence of mankind in the event of some as yet unknown ancient microbe being unearthed by the consistent destruction of rain forests that is accompanied by present day human expansion.
Raul Y. Tito 1, Dan Knights 2, Jessica Metcalf 3, Alexandra J. Obregon-Tito 1, Lauren Cleeland 1, Fares Najar4, Bruce Roe 4, Karl Reinhard 5, Kristin Sobolik 6, Samuel Belknap 6, Morris Foster 1, Paul Spicer 1, Rob Knight 3, Cecil M. Lewis Jr 1*
1 Department of Anthropology, University of Oklahoma, Norman, Oklahoma, United States of America, 2 Department of Computer Science, University of Colorado, Boulder, Colorado, United States of America, 3 Department of Chemistry and Biochemistry, University of Colorado, Boulder, Colorado, United States of America, 4 Department of Chemistry and Biochemistry, Advanced Center for Genome Technology, University of Oklahoma, Norman, Oklahoma, United States of America, 5 School of Natural Resources, University of Nebraska, Lincoln, Nebraska, United States of America, 6 Climate Change Institute and Department of Anthropology, University of Maine, Orono, Maine, United States of America