March 8 (UPI) -- Scientists have discovered another window into the Neanderthal's past -- dental plaque. New analysis of DNA trapped in ancient dental plaque suggests the early human relatives treated pain with salicylic acid, a plant hormone found in poplar plants and the active ingredient in aspirin.
By studying the genes hiding in ancient plaque, researchers can gain insight into the health and behavior of Neanderthals.
Researchers sequenced the DNA of plaque found on the fossil teeth of Neanderthal remains recovered from Spy Cave in Belgium and El Sidrón in Spain. They shared their results in the journal Nature.
"We found that the Neandertals from Spy Cave consumed woolly rhinoceros and European wild sheep, supplemented with wild mushrooms," Alan Cooper, director of the Australian Centre for Ancient DNA at the University of Adelaide, said in a news release. "Those from El Sidrón Cave on the other hand showed no evidence for meat consumption, but appeared instead to have a largely vegetarian diet, comprising pine nuts, moss, mushrooms and tree bark -- showing quite different lifestyles between the two groups."
DNA found in the plaque of one of the Spanish Neanderthals revealed evidence of a dental abscess and intestinal parasite. Scientists found ancient genetic remnants of salicylic acid and penicillium, the natural antibiotic mold.
"Apparently, Neandertals possessed a good knowledge of medicinal plants and their various anti-inflammatory and pain-relieving properties, and seem to be self-medicating," said Cooper. "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."
Scientists hope further analysis of ancient plaque will reveal the ways in which varying diets altered the microbiomes of humans and their relatives.