Dental plaque DNA reveals details about Neanderthals

When we talk about dental plaque, we don’t like to think about how long it sticks around if we don’t remove it. But evidently, it stays put for a long time. In March of 2017 an international team of researchers, led by the University of Adelaide’s Australian Centre for Ancient DNA (ACAD) and Dental School, with the University of Liverpool in the UK, used dental plaque samples of Neanderthals from nearly 50,000 years ago to gain remarkable new insights into their diet and behaviors, including their use of plants to treat illness and pain.

The research team compared and analyzed dental plaque samples ranging from 42,000 to around 50,000 years old from four Neanderthals found at the cave sites of Spy in Belgium and El Sidrón in Spain. These samples are the oldest dental plaque ever to be analyzed genetically.

The results showed that the Belgian Neanderthals primarily ate wild sheep and woolly rhinoceros, along with wild mushrooms. The Spanish samples revealed a largely vegetarian diet, comprised of pine nuts, moss, mushrooms, and tree bark, with no evidence in their DNA of meat consumption.

One interesting finding in one of the Spanish Neanderthals was the evidence of a large dental abscess, which was visible on the jawbone. His dental plaque DNA revealed that he was eating poplar, which contains the pain killer salicylic acid, the active ingredient in aspirin. They also detected a natural antibiotic mold (Penicillium), the fungus that produces penicillin. 

Professor Alan Cooper, Director of ACAD, stated: “Apparently, Neanderthals possessed a good knowledge of medicinal plants and their various anti-inflammatory and pain-relieving properties, and seem to be self-medicating. The use of antibiotics would be very surprising, as this is more than 40,000 years before we developed penicillin. Certainly our findings contrast markedly with the rather simplistic view of our ancient relatives in popular imagination.”

The study also revealed evidence of how the oral bacteria from each region differed, based on what our ancestors were eating. This view into the past provides ways to understand more about our evolutionary past through the microorganisms that were found.

To learn more about this fascinating journey into our history, read the article from The University of Adelaide