Genevieve von Petzinger: "Yes, we were capable. Yes, they were us."
Humans have been the most successful species on the planet (roaches and rats have done well, too). Scientists credit our success to three traits: technology innovation, group collaboration, and communication. Humans not only have all three abilities, but we excel at all three. The question of when we started being human and flexing our abilities has been coming under constant revision in recent years.

Until the 1990s historians pegged humanity's first creative explosion at about 40,000 years ago, a time of rapidly expanding variation on primitive stone tools. This is the era of the mesmerizing 32,000-year-old paintings in the caves at Chauvet or the ornate grave goods found at the burial site at Sungir outside of Moscow. One boy's burial garment was sewn with 4,500 ivory beads. A girl's had 5,000. Each bead is estimated to have taken an hour to produce, which means these strands were probably a year in the making, suggesting that the "primitive" beadmaker was thinking abstractly about death and spirituality in a disciplined way for a long time.

But recent discoveries in South Africa are pushing back the dates of when humans started acting human. The Blombos cave and the Diepkloof rock shelter in South Africa have turned up ostrich shells and pieces of ochre with ornate markings that date back 60,000 years ago. The shells are etched with simple geometric forms that are still used by Kalahari tribesmen to mark ownership of the shells, which they employ as water vessels.

These geometric forms present one of the biggest unsolved mysteries in pre-historic exploration. What did they mean? Why do they appear everywhere in such great numbers? Searching for answers is a young anthropologist named Genevieve von Petzinger, who is compiling a one-of-a-kind database at the University of Victoria in British Columbia, Canada. Her work categorizing the forms may offer important clues to the spread of early human expression.
Typology of Non Figurative Signs

Von Petzinger has identified 30 unique geometric signs that reoccur in caves throughout the world. Unfortunately she has no grand unifying theory behind them. There are patterns and clusters to them, but so far she can only guess at their meaning. She doesn't think it's a writing system. Some could be attempts at counting. She dismisses the idea they were done by aliens, even though people ask her that one every now and then. Some could be measuring time or inventorying goods. Archaeologists have found rocks with painting of salmon jumping out of a river with parallel lines drawn next to it. These could be marking years of excellent fish spawning or numbers of fish caught.

Some may be reflections from shamanic ritual. "Have you heard of entoptics? They're the shapes your eye can produce when you're in altered states. It's possible some are derived from shamanism," says von Petzinger, who was recently named a TED Fellow and will be speaking at TEDGlobal next week in Edinburgh, Scotland. The bulk of her master's thesis on the signs in French caves was published earlier this year as a cover story in the New Scientist. [Registration req. You can also click through this photo gallery.]

Anthropologists have written about the signs before, but von Petzinger is the first to methodically store each instance of a sign into a computer database. Currently it stores symbols from 147 of the 170 pre-historic sites in France. Her survey is now expanding to 450 sites on every continent. Each marking is entered into the database along with a rich amount of metadata: the number that appear, their color, site type and description, adjacent cave paintings, latitude and longitude, and date of appearance. She was able to catalog the signs of the caves in France remotely from her home in British Columbia using the earlier work of French researchers who had cataloged the markings but without any organization.

"It wasn't until I pulled it all together in the database that I became aware of how common they are," she says. "I've had more than one moment of clarity." Such as? "Complexity happened much earlier than we thought, well earlier than 30,000." By organizing the signs into a structured database, she is beginning to see how the sign patterns spread over geographic distances and how repeated pairings and clusters began to form over time.

Still, the geometric signs don't yield easy explanations about their purpose. They are often associated with painted animals but even then don't appear in patterns that would suggest they are referring to those figurative paintings. Peter Robinson, an editor at the Bradshaw Foundation, describes their appearance in one pre-historic site (emphasis added):
Such is the case in the Niaux Cave, in the foothills of the French Pyrenees. The main entrance...leads into a large and even-floored cavern, wide and high-ceilinged. The cave walls are smooth and clear, but empty of cave art. For the first 400 metres there are no paintings or engravings. But at a particular point the open cavern becomes restricted, caused by an ancient collapse of enormous jagged boulders from the ceiling. Here there is a choice - one can continue into the cave by climbing with considerable difficulty up over the debris, or else squeeze through a narrow but level passage to the left. As one emerges from this, and on either side of the opening, the paintings begin as symbols. Simple linear lines in red seem to mark the beginning of the painted cave; the beginning of the experience. These enigmatic and understated decorations continue, with a hundred or so red and black geometric signs - dashes, bars, lines, and series of dots - some painted using tools, some using fingers...They have been daubed strategically, sometimes opposite each other, sometimes on either side of a conspicuous fissure. Shortly after this, the animal figures appear, and the prehistoric dialogue continues to unfold.
At some point, von Petzinger says, the geometric shapes stopped changing. They became universals, the pursuit of which may also be a human urge. Around 20,000 years ago they began to be found in more regular clusters. Because of this she considers the geometric signs to be graphic communication but finds too many limitations to call it a language. Some may contain the roots of logographic languages like Chinese, which has 1,000s of symbols. She is working now toward dealing with their later use in a paper she is tentatively entitling, "So, Is It Writing?"

Over the next three years von Petzinger plans to travel and collect more first-hand images of paintings and signs. Since publishing her work she's gotten deluged with excited messages from people who want to help or know more. Why so much interest in humble signs, when the paintings of Lascaux, Altamira and Chauvet are so much more beautiful?

"I think it goes back to a time before groups, borders. This is more about our similarities as humans, rather than our differences."