July 19 (UPI) -- Neanderthals weren't dependent on lightning strikes and natural wildfires for their flames, new research suggests. The early human relatives were able to start their own fires.
When researchers found microscopic wear on flint hand-axes collected at Neanderthal archaeological sites, they recognized the signature of flint striking found around the hearths of early human settlements.
"I recognized this type of wear from my earlier experimental work," archaeologist Andrew Sorensen, professor at Leiden University in the Netherlands, said in a news release. "These are the traces you get if you try to generate sparks by striking a piece of flint against a piece of pyrite."
The hand-axes, however, were much older than the fire-making tools Sorensen had previously analyzed.
In the lab, researchers used advanced imaging to detail the unique microscopic signatures. The images revealed tiny C-shaped indentations, as well as parallel scratches, or striations -- all signatures of the type of rock-striking used to make sparks.
Sorensen and his colleagues found the same microscopic wear on dozens of hand-axes dated to 50,000 years ago, suggesting the practice of fire-starting was widespread among Neanderthals.
"Being able to make their own fire gives the Neanderthals much more flexibility in their lives," Sorensen said. "It's a skill we suspected, but didn't know for sure they possessed."
The findings, detailed this week in the journal Scientific Reports, suggests Neanderthals were capable of technological insights similar to those of early humans.