May 4 (UPI) -- How and why did naturalistic animal depictions suddenly appear in an abundance of cave paintings around 37,000 years ago?
In a new study, researchers from the University of York and Durham University present a new framework with which to analyze Palaeolithic art. The new approach combines elements of visual neuroscience, perceptual psychology and the archaeology of cave art.
In the paper, newly published in the Cambridge Archaeological Journal, scientists argue hand marks practiced by Neanderthals some 64,000 years ago -- both positive prints and negative stencils -- first sparked the concept in the minds of early humans that a painted symbol could be representative.
But how did cave painters move from hand marks to more complex animal depictions?
Researchers suggest hunters had to be hyperaware of the contours of the animals they hunted, so much so that they could recognize the shapes and outlines of animals hiding in the dark and camouflaged by their surroundings. Their survival depended on it.
This tendency hasn't much changed, researchers contend.
"In short, we are preconditioned to interpret ambiguous shapes as animals," the scientists Derek Hodgson and Paul Pettitt wrote in an article published in The Conversation.
This precondition, the logic goes, was reinforced by the contours and textures of caves. The logic borrows from visual neuroscience experiments, several of which have shown humans preconditioned to recognize faces begin to see faces among ambiguous shapes. Early humans began to see animals among the cracks and curves of the cave wall.
"Caves are full of suggestive cues," the researchers wrote. "They are dangerous places, often inhabited by predators, thereby stimulating increased arousal levels."
Eventually, early humans realized they could create an animal depiction by adding a few graphic features to the suggestive cracks and contours.
Several archaeological sites suggest early humans inhabited the same caves used by Neanderthals. It's possible Homo sapiens saw the hand stencils left by Neanderthals and took their art one step further.
Unlike other studies examining the birth of animal depictions and other cave art breakthroughs, Hodgson and Pettitt present a testable theory, one they believe can and should be fairly challenged.
"Our approach is open to refutation. For example, if someone finds depictions of animals or similar that predate the first hand marks, this would overturn our main proposition," they wrote. "Similarly, if earlier figurative depictions come to light that do not derive from natural features, this would also challenge our theory."