Homo Sapiens Get Smart in Africa
Carvings Point to Africa as Birthplace for Modern Thinking

Two pieces of engraved red ochre found in a South African cave suggest that modern human behavior started in Africa, not Europe. Photo: © Science

Jan. 10, 2002-- About 35,000 years ago in Europe, people began painting on the walls of caves. Those first works of art were long thought to be signs of the birth of abstract thinking. Along with bone tools, they represent what archaeologists call the "creative explosion" in human evolution.

Recent discoveries in Africa, however, suggest that "modern" human behavior, as experts call it, may have started much earlier -- and not in Europe. For All Things Considered, NPR's Christopher Joyce reports on what two pieces of ochre are revealing about human evolution.

"One of the holy grails of human evolutionary history," says Smithsonian Institution anthropologist Richard Potts, "is to understand when people became modern." Scientists are trying to determine when humans, already equipped with large brains and walking upright, began to live in a society.

From sites in France and Spain, scientists have found bits of engraved bone, some with patterns of cross hatching, that suggest something was awakening in the human mind.

"You look at something like this and you wonder, what could that have ever been used for? And we can't imagine any particular function or use other than communicating," says Potts, human origins director at the National Museum of Natural History.

Such cross-hatched engravings, along with cave paintings, point to a so-called creative explosion. They suggest that humans could think symbolically, and suddenly, weren't so primitive.

But a small limestone cave in South Africa is now calling that shining moment in human evolution into question.

Christopher Henshilwood, an archaeologist with the State University of New York at Stony Brook, started digging in Blombos Cave in 1991, and uncovered well-crafted bone tools that he says are too elegant to just be tools. He also found pieces of ochre, an iron ore historically used to paint skin or color stone. Two specimens, each about the size of a piece of chalk, have been decorated with a geometric design -- cross hatchings and parallel lines. Henshilwood says they're clearly artwork.

"The ochres are the cherry on the top because here we have clear evidence for cognitive ability, the ability of humans to think abstractly," says Henshilwood, who works at the South African Museum in Cape Town.

The discoveries are causing a stir because the ochre fragments date back 77,000 years, long before the creative explosion in Europe. Scientists say the pieces suggest not an explosion, but a gradual learning curve, beginning not in Europe, but in Africa.

Some archaeologists say they need to see more evidence to conclude that the human "awakening" occurred in Africa that long ago. Other African sites of similar age show nothing like these tools and engravings. But archaeologist Curtis Marean of Arizona State University, who has worked at sites near Blombos Cave, says up until now scientists just haven't looked in the right places in Africa, or in a careful way.

Blombos isn't a fluke, says Marean. "Once again, in terms of human evolution, we are seeing Africa as being precocious: Bipedal hominids evolved in Africa; the first real increase in brain size occurred in Africa; and now, we are beginning to see that the last great advance, the development of modern behavior, was made in Africa as well."

In Depth

 Browse for other NPR stories about human evolution.

Other Resources

• Read more about the work at Blombos Cave.

• Explore the human evolutionary tree, courtesy of George Mason University.

• Take an online tour of the National Museum of Natural History's human evolution exhibit.