Neanderthals created stone tools held together by a multi-component adhesive, a team of scientists has discovered. Its findings, which are the earliest evidence of a complex adhesive in Europe, suggest these predecessors to modern humans had a higher level of cognition and cultural development than previously thought.
The work, reported in the journal Science Advances, included researchers from New York University, the University of Tübingen, and the National Museums in Berlin.
“These astonishingly well-preserved tools showcase a technical solution broadly similar to examples of tools made by early modern humans in Africa, but the exact recipe reflects a Neanderthal ‘spin,’ which is the production of grips for handheld tools,” says Radu Iovita, an associate professor at NYU’s Center for the Study of Human Origins.
The research team, led by Patrick Schmidt from the University of Tübingen’s Early Prehistory and Quaternary Ecology section and Ewa Dutkiewicz from the Museum of Prehistory and Early History at the National Museums in Berlin, re-examined previous finds from Le Moustier, an archaeological site in France that was discovered in the early 20th century.
The stone tools from Le Moustier—used by Neanderthals during the Middle Palaeolithic period of the Mousterian between 120,000 and 40,000 years ago—are kept in the collection of Berlin’s Museum of Prehistory and Early History and had not previously been examined in detail. The tools were rediscovered during an internal review of the collection and their scientific value was recognized.
“The items had been individually wrapped and untouched since the 1960s,” says Dutkiewicz. “As a result, the adhering remains of organic substances were very well preserved.”
The researchers discovered traces of a mixture of ochre and bitumen on several stone tools, such as scrapers, flakes, and blades. Ochre is a naturally occurring earth pigment; bitumen is a component of asphalt and can be produced from crude oil, but also occurs naturally in the soil.
“We were surprised that the ochre content was more than 50 percent,” says Schmidt. “This is because air-dried bitumen can be used unaltered as an adhesive, but loses its adhesive properties when such large proportions of ochre are added.”
