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Kneeprint Found Near 175,000-Year-Old Stalagmite Structures in Bruniquel Cave
A possible kneeprint in clay preserved by calcium carbonate offers new clues about Neanderthals who built mysterious structures deep inside a French cave. Sophie Verheyden presented the findings on 4 May at the European Geosciences Union meeting in Vienna. The discovery comes as researchers explore whether DNA from the impression could link directly to its Neanderthal builders.
May 9, 7:15 AM·2m read3 sources
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An impression in clay that could be a kneeprint was found next to a stalagmite circle in Bruniquel cave in south-west France. The kneeprint impression was made around 175,000 years ago. Neanderthals built the strange stalagmite circle deep inside the cave more than 300 metres from the entrance, where it is pitch black.
The stalagmite circles in Bruniquel cave were discovered in the 1990s and described in a 2016 paper by a team including Sophie Verheyden, who works at the Royal Belgian Institute of Natural Sciences. Some of the broken stalagmites are more than 20 centimetres thick at the base.
The bases of a handful of the broken-off stalagmites have been located, with the breakage dated to around the same time that the stalagmite circles were built.
Both the structures and the broken stalagmites were dated by measuring radioactive isotopes in the calcite growths. The largest stalagmite circle is around 7 metres in diameter. Traces of fire suggest the circles were lit.
The cave impression has been covered and preserved by a thin layer of calcium carbonate. A bear specialist examined the impression and concluded it isn’t a bear print. Sophie Verheyden met with Mareike Stahlschmidt at the University of Vienna, who has shown that DNA can diffuse into calcite and be preserved by it.
Mareike Stahlschmidt said that for Bruniquel cave it is worth a shot to look for DNA. Forensic studies of kneeprints have shown that they can contain DNA from skin cells, hair or blood. Homo sapiens was not in Europe around 175,000 years ago.
The entrance to Bruniquel cave collapsed at least 140,000 years ago and remained closed until its rediscovery by cavers in 1990. Sophie Verheyden said: “It’s just a hypothesis.
Verheyden presented her findings on 4 May at a meeting of the European Geosciences Union in Vienna. Her team is developing ways to fingerprint the stalagmites based on their mineral composition to determine where in the cave the broken ones came from.
