Researchers from Oregon State University (OSU) studied four ticks found in the Dominican Republic, and the sap-trapped critters revealed a large grouping of cells that bear a close resemblance to Borrelia, a type of bacteria that to this day causes Lyme disease.
The ticks represent the oldest known fossil evidence of Borrelia, and they suggest the startling notion that tick-borne bacteria has likely been delivering Lyme disease to humans for as long as there have been humans.
Soft-bodied bacteria aren’t often preserved in the fossil record, but amber, which starts out as tree sap, makes a great preservation medium, as it slowly bides its time and becomes a mineral.
Lyme disease itself was not even identified until 1975. The disease — which hampers the joints, heart and central nervous system — can be cured with antibiotics if it’s caught early, but it’s often misdiagnosed.