Treponema pallidum bacteria cause diseases including syphilis Science Photo Library / Alamy Traces of a bacterium related to syphilis have been found in a bone from a person who lived in the mountains of Colombia over 5000 years ago. The discovery shows that this group of corkscrew-shaped bacteria was infecting humans thousands of years earlier than previously thought, before the rise of intensive agriculture, which many researchers consider a catalyst for the spread of pathogens. Today, three subspecies of the bacterium Treponema pallidum cause the diseases syphilis, bejel and yaws. The deep history of these ailments is murky, and researchers have debated where diseases like syphilis arose and how they became widespread. Ancient bacterial DNA and markers of infection on skeletal remains lend us some clues, but these are rare and can be ambiguous. So, when researchers studying the ancient DNA of 5500-year-old human remains in the Bogotá savannah detected the genome of Treponema pallidum in a human leg bone sample, it was a surprise. “This finding was completely unexpected, because the individual studied had …