Prehistoric Human Biology as Inferred from Dental Calculus

Advanced molecular methods have revealed a startling fact - that our bodies are not merely ourselves. Microorganisms comprise more than half of our cells, contain 99% of our genes, and perform vital functions in digestion, immunity, and homeostasis. Yet while we have made great strides in revealing the diversity, variation, and evolution of the human genome, we know surprisingly little about the microbial portion of ourselves, our microbiome. Recently, it has been discovered that dental calculus (calcified dental plaque) entraps a rich biomolecular record of the oral microbiome that preserves for thousands of years. Analysis of ancient dental calculus has revealed a wide range of commensal and pathogenic bacterial taxa, bacteriophages, human and dietary biomolecules, and an abundance of DNA “dark matter” from unknown and uncharacterized organisms. This talk explores how emerging ancient dental calculus research is changing the way we investigate the human past and how this is leading to a deeper understanding of human biology and evolution.