A 59,000-year-old Neanderthal tooth found in a Siberian cave shows signs of deliberate drilling to treat a deep cavity, pushing back the earliest evidence of dentistry by about 45,000 years. The lower second molar – plagued by suspected bacterial decay – features tell-tale marks of experienced stone-tool boring, in three stages, down to the pulp. While the procedure would have been excruciating, it probably led to pain relief in the individual, who went on to chew with the tooth, possibly for years, says Kseniya Kolobova at the Russian Academy of Sciences. “Our discovery challenges prejudices about Neanderthal cognition directly, showing that they were capable of causal reasoning about disease,” she says. “We trust the evidence from our microscopes.” In the Altai mountains of south-western Siberia, Russia – where Neanderthals migrated from Europe about 70,000 years ago – researchers discovered a lower molar with a large, irregularly shaped concavity comprising three partially overlapping dips into the entire pulp chamber. At first, the team thought it was just a tooth that got broken before or after death, …

Neanderthals may have used tar made from tree bark as an antiseptic to treat wounds. Modern-day experiments with birch tar show that it has antibiotic properties, regardless of how it is made, hinting that Neanderthals could have discovered its medicinal uses. The finding adds to a growing body of evidence suggesting that Neanderthals used medicinal plants to treat injuries and diseases. “Birch tar as a substance has been known for quite a while from the late Pleistocene, specifically from Neanderthal sites across Europe,” says Tjaark Siemssen at the University of Oxford. “It’s pretty clear that it’s been used as an adhesive,” says Siemssen, for instance, to attach sharpened stone heads onto wooden spears. However, he says that may not have been its only use. In some Indigenous communities in recent centuries, birch tar has been applied as a medicinal ointment. Among the Mi’kmaq communities of eastern Canada, it is called maskwio’mi and is used as a broad-spectrum antibiotic. To find out if the birch tar produced by Neanderthals might have had similar properties, Siemssen and …