Oct 11, 2013 05:05 PM EDT By Staff Reporter, UniversityHerald Reporter

Women were probably the world's first artists, according to National Geographic. Their fingerprints were literally all over their work.

Penn State Archaeologist Dean Snow didn't use DNA testing or anything complex algorithm for his perspective-changing discovery. He needed only to measure the lengths of two fingers, Nat Geo reported.

Snow based his findings off previous research by John Manning, which revealed an odd difference between the finger lengths of men and women: men tended to have longer ring fingers than index fingers; for women there was no difference.

With Manning's discovery in mind, Snow pulled open a book of cave art and spotted two female hands.

"I looked at that thing and I thought, man, if Manning knows what he's talking about, then this is almost certainly a female hand," Snow said.

Snow studied cave drawings from all around the world, including the most famous samples from the regions of southern France and northern Spain. According to Nat Geo, cave art from those two areas can be up to 40,000 years old. Snow decided to use French and Spanish drawings as the basis for his study.

Though the program he used for analyzing measurements was only able to predict with 60 percent accuracy, Snow's samples were actually much more distinct than he predicted. It turned out that finger differences between men and women were actually greater 40,000 years ago than today. Snow would test 32 samples in all; 24 of them were digit-ally females.

"There has been a male bias in the literature for a long time," said Snow, whose research was supported by National Geographic. "People have made a lot of unwarranted assumptions about who made these things, and why.

"In most hunter-gatherer societies, it's men that do the killing. But it's often the women who haul the meat back to camp, and women are as concerned with the productivity of the hunt as the men are," Snow said. "It wasn't just a bunch of guys out there chasing bison around."

Snow didn't know why women chose to leave their handprint.

"I have no idea, but a pretty good hypothesis is that this is somebody saying, 'This is mine, I did this,'" he said.

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