Scientists believe ancient stone tools discovered in Brazil are the work of capuchin monkeys, not early humans, art and design website Artnet reported, citing an academic paper.
“We are confident that the early archaeological sites from Brazil may not be of human origin, but may belong to capuchin monkeys,” archaeologist Agustín M. Agnolín and paleontologist Federico L. Agnolín wrote in a paper published in the peer-reviewed journal Science The Holocene in November.
The article said archaeologists uncovered what they believe to be ancient stone tools, made from locally occurring quartz and quartzite cobbles, during previous excavations at Pedra Furada – a collection of over 800 archaeological sites in Piauí in northeastern Brazil.
The oldest of the stone tools discovered appear to be up to 50,000 years old, according to the article, leading some academics to theorize that it provided evidence of early human habitation in the region.
However, unexpected findings from 2016 posed a challenge to that theory.
The findings showed that capuchin monkeys in northeastern Brazil are capable of making and using a wide variety of stone tools.
This raised the possibility, first suggested in 2017, that apes – not humans – could be responsible for producing the Pedra Furada finds.
And according to Agnolín and Agnolín, the researchers behind it The Holocene article, there is now a compelling body of evidence to suggest that the tools were not man-made.
“Our review of the evidence suggests that the ancient sites in Brazil do not actually belong to the first Americans, but are in fact the product of ape activity,” Federico L. Agnolín told Argentina’s National Scientific and Technical Research Council (CONICET).
The researchers compared the tools found at Pedra Furada with those made by capuchin monkeys today.
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“The result was surprising: there was no difference between the supposed human tools from 50,000 years ago and those produced by apes today,” Agustín M. Agnolín told CONICET.
The researchers looked at previous research and observations of capuchin monkey populations showing that the primates use small stones as hammers and large, flatter stones as anvils to crack open nuts and seed pods.
“The result is that the rocks used often break, generating stone fragments very similar to those produced by humans when they carve stone tools,” said Agustín M. Agnolín, to CONICET’s news release.
In addition to this, the researchers said in The Holocene article that there was no evidence to suggest a trace of human presence, noting the lack of hearths or traces of dietary remains.
“Our study shows that the tools from Pedra Furada and other nearby sites in Brazil were nothing more than the product of capuchin monkeys crushing nuts and stones around 50,000 years before the present,” Federico L. Agnolín told CONICET.
This article was originally published by Business Insider.
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