The source of creativity / Heather Pringle

New evidence of ancient sophistication forces scientists to re-date when our ancestors started thinking "outside the box"

Exhibit 779 hangs in the Louvre Museum in Paris, unsigned and undated, behind thick glass in the "Sal des Etats" illuminated by precious light. A few minutes after nine o'clock every morning, except for Tuesdays when the museum is closed, Parisians and tourists, art lovers and the curious begin to pour into the room. Like bees in a hive, their muffled voices blend into one another and coalesce into a uniform hum. Some of them crane their necks to get a better look. Others stretch their hands up and take pictures with their cell phones of the display. But most lean forward with a look of wonder on their faces as they contemplate mankind's most famous creation: Leonardo da Vinci's Mona Lisa.

The Mona Lisa, completed in the early 16th century, has a mysterious, out-of-this-world beauty that no other portrait has before it. To create such a painting, Leonardo, who is known to have once written that he aspires to "work miracles", developed a new artistic technique which he called "spumato", meaning "smoke". Over several years he applied thin layers of transparent glaze, some of them not as thick as a red blood cell, to the painting, probably using the sensitive tip of his finger. Leonardo piled up to 30 such layers on top of each other and with their help gently softened the lines and color transitions in the picture until the impression was created that the entire work is hidden behind a smoke screen.

There is no doubt that the Mona Lisa is the work of an inventive genius, a masterpiece that stands in honor alongside the music of Mozart, the jewels of Faberge, the choreography of Martha Graham and other similar classics. But these famous works are only the most sublime example of a trait that is probably inherent in humans and promotes Dana: the ability to create something new and desirable and the talent to persevere and improve existing technologies and programs, from the latest Japanese cars that do not emit gases into the environment to the beautifully designed spaceships standing on the NASA launch pads "A. According to Christopher Henshilwood, an archaeologist at the University of the Witwatersrand in Johannesburg, modern humans are made-up inventors. We are making progress with technology and are constantly experimenting with it.

Vigorous scientific research is trying to find out exactly how we acquired this seemingly infinite creative ability - after all, we were not always such creative inventors. Although our human lineage originated in Africa about six million years ago, the first human family left no clear evidence of ingenuity for the first 3.4 million years or so. The evidence we have suggests that they gathered their food, from animals and plants, with their hands using simple tools such as digging sticks or sticks and did not preserve food. Then, at some point in time, nomadic hominins began to strike pebbles with hammerstones, chipping them and making them into cutting tools. There is no doubt that it was amazing sophistication, but after that there was a long stagnation during which it seems as if there was no noticeable progress on the creativity front. It seems that our ancestors continued to hammer stone and produce the same multi-purpose hand axes for about 1.6 million years, almost without changing and improving the initial pattern. "These tools are pretty stereotypical," says Sally McBrearty, an archaeologist at the University of Connecticut.

So, when did human thought begin to come up with new ideas for creating technology and art? Until recently, most researchers believed that this happened at the beginning of the Upper Paleolithic period, about 40,000 years ago. At the same time, Homo Spines broke out in Europe in what seemed like a sudden and miraculous binge of inventiveness: he began to fashion beads from shell beads, to decorate the walls of caves with elegant paintings depicting wild oxen and other animals from the Ice Age, and to create a new and wide selection of stone and bone tools with stone hammers. The findings advanced a common theory that suggested a random genetic mutation that occurred around the same time triggered a sudden leap in human consciousness and ignited a "big bang" of creativity.

However, new evidence casts great doubt on the mutation theory. Over the past ten years, archaeologists have uncovered much earlier evidence of advanced art and technology, suggesting that the human capacity for concocting new ideas developed long before the accepted date and even before the appearance of Homo sapiens 200,000 years ago. And yet, although our creativity was born very early, it burned in secret for thousands of years before igniting among our own people in Africa and Europe. The evidence seems to indicate that our ingenuity did not arise all at once in its full glory in the later stages of our evolutionary history, but rather gathered strength over hundreds of thousands of years, driven by a complex mix of biological and social factors.

When exactly did the human race begin to think outside the box and what factors coalesced to eventually ignite our creative fires? To understand the scenario that explains this we must follow a detective story consisting of several threads of evidence. The first thread suggests that the biological roots of our creativity lie in the distant past, much further than scientists previously thought.

If the invention

For a long time the single most important measure of the existence of modern human consciousness, in the eyes of archaeologists, is the use of symbols. They believe this to a large extent because this indicates the ability to maintain language, a distinct hallmark of man. And so the spectacular cave art of the Upper Paleolithic period is a clear sign of the presence of people who thought like us. But recently experts have begun looking for clues to other types of modern behavior and foreshadowing in the archaeological record. Indeed they found fascinating clues.

Lynn Woodley, an archaeologist at the University of the Witwatersrand, has spent most of her career studying ancient thinking. In the 90s, the research led her to begin excavations in Sibudu Cave, located about 40 kilometers north of Durban in South Africa. Two years ago, she and her team discovered a strange, white, fibrous layer of plant material there. To Woodley, this pale, frayed, crumpled sheet looked like an ancient bedding. It contained leaves of reeds and other plants that people in later times spread on the ground to sit or sleep on. But maybe it was the wind that swept the leaves and created this layer? The only way to distinguish between the two hypotheses was to protect the entire layer in plaster and bring it to the laboratory. "It took us three weeks to plaster everything," Woodley recalls, "and I was really grumpy all those days. I kept wondering in my heart, 'Am I wasting three weeks of work in the field?'"

But Woodley's gamble paid off handsomely. In December 2011, she and her colleagues reported in the journal Science that the inhabitants of Sibodu Cave selected leaves from a single species of leafy plant that grew in the area to prepare a bed for themselves 77,000 years ago, nearly 50,000 years before any other recorded example. What impressed Woodley most was the cave dwellers' sophisticated knowledge of the area's flora. Analysis of the sample proved that the leaves were taken from the plant Cryptocarya woodii, a tree that contains small amounts of natural insecticides and maggoticides that are effective against mosquitoes that still carry deadly diseases today. "And that's something very useful in your bed, especially if you live by a river," says Woodley.

But the creative minds of the people of Sivodo did not stop there. It is likely that they developed traps to capture small antelopes whose remains are scattered around the site. They also made bows and arrows to hunt more dangerous animals - as evidenced by the size, shape and weathering patterns of some stone arrowheads found in the cave. What's more, the Sivodo hunters concocted some useful new chemicals. On the arrowheads collected in the cave were found black remnants of a substance that had been applied to them in the past. In the lab, Woodley's team fired beams of high-energy charged particles at this black substance and found that it contained a multi-ingredient glue that attached the arrowheads to wooden sticks. Woodley and her team tried to mimic the process and create such adhesives themselves. They mixed grains of ocher [an iron oxide mineral] of various sizes with plant resins and heated the mixture over fires. In an article in Science, in which they described the results, the team members wrote that the inhabitants of Sibodu were probably "talented chemists, alchemists and fire technicians" as early as 70,000 years ago.

Researchers elsewhere in South Africa have recently uncovered many other traces of early and early inventions. The hunter-gatherers who lived in Blombos Cave 100,000 to 72,000 years ago, for example, carved patterns on blocks of ocher; Awls were fashioned from bone, perhaps to sew leather garments; They decorated themselves with strings of multicolored shell beads and created an art studio where they ground red ocher and housed it in vessels made from abalone shells (abalone) - the earliest known example of such use of shells. West of there, at the Pinnacle Point cliff site, humans processed the stones they worked with 164,000 years ago: they heated a poor-quality local rock called silcrete over a controlled fire to turn it into a shiny material that was easy to chip. "We're finding behaviors that we couldn't even imagine ten years ago," says Henshilwood.

Moreover, technological innovation is not reserved only for modern humans. Other hominins were also gifted with a creative spark. In northern Italy, the team of archaeologist Paul Peter Antoni Mazza from the University of Florence discovered that the Neanderthals, the closest species to us who first appeared in Europe about 300,000 years ago, knew how to brew glue from the resin of white tree bark to stick stone chips to wooden handles and create tools with a handle as early as 200,000 years ago . Similarly, a study published in Science in November 2012 concluded that stone halves discovered at the Cathu Pan 1 site in South Africa were used as deadly arrowheads 500,000 years ago, probably by Homo heidelbergensis, the last common ancestor of Neanderthals and Homo sapiens. And an ancient layer containing plant ash and burnt bone fragments in South Africa's Wonderwerk Cave suggests that even an earlier hominin, Homo erectus, learned how to make fire for warmth and to protect itself from predators as early as a million years ago.

Even our very distant ancestors were able, from time to time, to come up with new ideas. At two sites near the Kada Gona River in Ethiopia, a team led by paleoanthropologist Sileshi Semao from Indiana University in Bloomington found the earliest stone tools to date: sharp, coarse stone chips that were thrown by Australopithecus garhi, or a species close to it, 2.6 million years ago, and which were probably used to Strip the meat from animal bones. These tools seem crude to us, a very long way from the smartphones, laptops and tablets that come off the production lines today. "But when there were only naturally formed objects in the world, the talent to imagine something and make it a reality seemed almost like magic," wrote the thinking researcher Leanne Gabora from the University of British Columbia and the psychologist Scott Barry Kaufman, now at New York University, in a chapter they co-authored in "The Cambridge Guide ' for creativity" (Cambridge University Press, 2010).

thinking and creating

As impressive as these early flashes of creativity may be, the depth of the gaping innovation gap between modern humans and our more ancient ancestors remains to be explained. What changes in the brain distinguish us from our predecessors? Researchers are beginning to unravel this puzzle by looking closely at XNUMXD scans of the craniums of ancient hominins and by examining the brains of our closest evolutionary carnivores, the chimpanzees and bonobos, whose ancestors split from our lineage about six million years ago. Their data shows how much the gray matter of humans has changed over time.

In general, natural selection favored large brains in humans. While the average skull volume of Australopithecus remains is estimated to be about 450 cubic centimeters, about the same as that of chimpanzees, Homo erectus had a volume more than double that 1.6 million years ago: 930 cubic centimeters on average. And 100,000 years ago, the average skull volume of Homo sapiens was 1,330 cc. According to an estimate, within this spacious brain cell about 100 billion nerve cells processed information and transmitted it along the length of about 165,000 kilometers of myelin-wrapped fibers and across about 0.15 quadrillion synapses. "And if you look at the correlation between this data and the archaeological evidence," says Dean Falk, a paleoneurologist at Florida State University, "there seems to be a relationship between brain size and technology or intellectual productivity."

But brain size wasn't the only change over time. Physical anthropologist Katrina Semendeferi of the University of California, San Diego studies the prefrontal cortex, a part of the brain that apparently orchestrates thoughts and actions to achieve goals. Samandfry and her colleagues examined this region in modern humans, chimpanzees and bonobos and found that several important subregions in this part of the brain underwent extensive reorganization during hominin evolution. Brodmann's area number 10, for example, which is involved in carrying out plans and organizing sensory input, nearly doubled in volume in the human brain after chimpanzees and bonobos diverged from the human family tree. Moreover, the horizontal spaces between the nerve cells in this subregion expanded by almost 50% and created space for more axons and dendrites. "This means that there may be more complex and longer-term links, and thus it is possible to get a combination of information and complex communication between the nerve cells," says Falk.

Deciphering the mystery of how a reorganized and larger brain spurs creativity is not simple. Gabora believes that psychological studies examining creative humans will provide the key to the puzzle. Such people are excellent twig collectors, she explains. When faced with a problem they let their minds wander, allowing thought or memory to spontaneously evoke each other. These free associations encourage analogies and stimulate outside-the-box thinking. And so, when such people cling to a vague idea for solving the problem, they switch to a more analytical way of thinking. "They then focus exclusively on the relevant features," Gabora says, and begin polishing an idea to make it workable. It is highly likely that larger minds resulted in an increased capacity for free associative thinking, Gabora says. In a brain composed of many billions of nerve cells, more stimuli can be encoded. Also, more neurons participate in the coding of a certain event. This allows the construction of a memory with a better separation capacity and with more possible paths that allow one stimulus to be linked to another. Imagine, for example, a hominin that rubbed against a thorny bush that injured its flesh, Gabora suggests. Australopithecus would code the event simply: a slight pain and a certain characteristic of the bush. But Homo erectus, with its larger cluster of nerve cells, could conceivably encode many aspects of the event including the spikes and its wounded flesh. Then, when this hominin went hunting, its need to kill its prey might have activated the memory areas of its brain that coded for split flesh. This reminded him of his own encounter with the sharp thorns of the bush. This memory, in turn, might inspire him with a new idea for a weapon: a pointed arrowhead.

But big-brained hominins could not afford to stay too long in a contemplative mood where everything immediately triggers a flood of memories, some important and others unhelpful. Their survival depended mostly on analytical thinking by default. Our ancestors therefore had to develop a way that would allow them to move smoothly from one state of consciousness to another through slight changes in the concentration in the brain of neurotransmitters such as dopamine and others. Gabora now speculates that it took Homo sapiens tens of thousands of years to fine-tune this mechanism before humans could reap the full benefits of their large minds. She is now testing these ideas with her students using an artificial neural network. They simulated in the computer model the ability of the brain to move from the analytical state to the associative state in order to discover how it can help to break through a cognitive impasse and see things in a new way. "The addition of nerve cells is not enough," says Gabora. "You have to be able to use that excess gray matter." Once the last piece of this biological assembly found its place, perhaps 100,000 years ago or a little more, the primitive mind became a virtual explosives box waiting only for the right social circumstances to detonate.

rely on brilliant intelligence

In the fall of 1987, two researchers from the University of Zurich, Christoph and Hedwig Bosch, noticed a behavior they had not seen before among a group of chimpanzees in the Thai National Park in the Ivory Coast. A female chimpanzee approached a nest of warring ants, stopped and picked up a thin branch from the ground. She stuck one end of the branch in the loose soil above the nest opening and waited until the female warriors defending it attacked. When the dark swarm rose up the stick to a height of about 10 centimeters, the chimpanzee retrieved it, quickly rolled it into her mouth and devoured the ants. She repeated the process over and over until she was satisfied.

Chimpanzees are very skilled at using many different tools. They crack nuts with stones, draw water using leaves in niches in tree trunks and uproot nutritious roots with digging sticks. But they seem unable to rely on this knowledge to advance or create more advanced technology. “Chimps can show other chimps how to hunt termites,” says Henshilwood, “but they don't improve the idea. They don't say, 'Let's do it with another device,' they just repeat the same thing over and over again." Modern humans are not limited in this way. In fact, every day we use the ideas of others and add our own spin to them, change after change, until we end up producing something new and very complex. No single person, for example, invented all the complicated technology inherent in a laptop computer. Such technological achievements have emerged from the creative insights of generations of inventors.

Anthropologists call this talent for cultural progress in stages a "cultural cycle". It requires, first and foremost, the ability to pass knowledge from person to person, or from generation to generation, until someone arrives with an idea for improvement. Lewis Dean, an expert on primate behavior, who currently works at the Psychological Society in London, and four of his colleagues published an article in March 2012 in the journal Science explaining why humans are capable of this, while chimpanzees and capuchin monkeys are not. Dean and his team designed an experimental puzzle box that requires overcoming three stages of increasing difficulty, one after the other. Then they introduced the box to groups of chimpanzees in Texas, capuchin monkeys in France and kindergarten children in England. Only one of the 55 non-human subjects, a chimpanzee, reached the highest level after 30 hours of trials. The children, on the other hand, were much more successful. Unlike the monkey groups, they worked cooperatively: they talked, encouraged each other, and showed each other how to do the task the right way. After two and a half hours, 15 of the 35 children reached the third level.

Equipped with these social skills and mental abilities, our ancestors had no difficulty in transferring knowledge to others, a transfer that is a necessary prerequisite for gradual cultural progress. However, something more was needed to set this cultural spinning wheel in motion and push Homo sapiens in Africa 90,000 to 60,000 years ago to new creative heights, and in Europe 40,000 years ago. Mark Thomas, an evolutionary geneticist at University College London, believes that demographics have given this push. His premise is simple. The larger a group of hunter-gatherers, the greater the chances that one of its members will come up with an idea that can advance technology. More than that, there is a greater chance that individuals living in a large group and rubbing against each other in everyday life will learn something new compared to the chances of individuals living in small and isolated groups. "It doesn't matter how smart you are," says Thomas. "But how connected you are."

To test this idea, Thomas and two of his colleagues developed a computer model that simulates the effects of demography on the cultural ratchet process. They used genetic information taken from present-day Europeans to estimate the size of human populations in Europe at the beginning of the Upper Paleolithic, a period whose remains indicate a surge in creativity. From this data they calculated the population density at that time. Then the researchers examined the changes in the African population over time, and simulated its growth and migration patterns on a computer. Their model showed that before 101,000 the populations in Africa reached the same density that prevailed at the beginning of the Upper Paleolithic period in Europe. According to the archeological evidence this happened just before innovation in sub-Saharan regions began to take off. Large social networks thus stimulate human creativity.

New archaeological evidence, published in an article in the journal Nature in November 2012, illuminates a period of technological renaissance that occurred following the increase in population density in South Africa. 71,000 years ago Homo sapiens at Finkle Point developed a complex technological process for making light stone blades for arrowheads and passed the information on. According to the recipe, silcrete stones must be heated to a certain temperature to improve its ability to crack and break into chips, shatter the finished material, spray it into blades no longer than two centimeters and mount them on wooden or bone handles with self-made glue. "Like viruses," archaeologists Fiona Coward of Royal Holloway, University of London, and Matt Grove of the University of Liverpool wrote in a 2011 paper in the journal Paleoanthropology, "so too cultural innovations require very specific social conditions to spread through society, and first and foremost ... large interconnected populations and the ability to 'stick' each other."

And this idea brings us to the crowded, bustling and connected world in which we live today. Never before have so many people been crammed together in such vast cities and able, with a few keystrokes, to access such vast realms of knowledge and share new ideas, plans, and designs with each other on social networks deployed on the Internet. And innovation has never advanced at such a rapid and dramatic pace, filling our lives with new fashions, new electronics, new cars, new music and new architecture.

Five hundred years after Leonardo da Vinci created his most famous work, we applaud his innovative genius, a genius that rests on the countless ideas and inventions of a lineage of artists stretching back in time to our Paleolithic past. And even today, a new generation of artists looks at the Mona Lisa with the desire to transform it into something fresh and spectacularly creative. The lineage of human innovation is unbroken. In our incredibly interconnected world, man's unique talent for new creation races before us.

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on the notebook

Heather Pringle is a Canadian science reporter and associate editor of the journal Archaeology.

in brief

Scientists have long believed that early humans were at a creative impasse until about 40,000 years ago. Then their powers of innovation seem to have unexpectedly burst forth.

Archaeological discoveries in recent years show that our ancestors had flashes of brilliant talent much earlier.

The findings show that the human talent for innovation appeared hundreds of thousands of years ago under the push of both biological and social factors.

Findings

A vibrant genius

Surprisingly early finds demonstrating technological and artistic ingenuity suggest that human creativity bubbled for hundreds of thousands of years until it reached a boiling point about 90,000 to 60,000 years ago in Africa, and about 40,000 years ago in Europe. It seems that social factors, including an increase in the size of the population, increased the innovation talent of our ancestors. These factors increased the chances that a single person in the group would come up with a new idea for a technological breakthrough and also supported the connectivity between the groups that allowed them to exchange ideas with each other. The timeline before you outlines the earliest evidence yet discovered of important innovations that led to the cultural boiling point.

And more on the subject

Middle Stone Age Bedding Construction and Settlement Patterns at Sibudu, South Africa. Lyn Wadley et al. in Science, Vol. 334, pages 1388-1391; December 9, 2011.

Hominin Paleoneurology: Where Are We Now? Dean Falk in Progress in Brain Research, Vol. 195, pages 255-272; 2012.