Randall White with Alan Alda in the Abri Castanet rock shelter excavation. Credit: Maggie Villiger

By Randall White, New York University

I have had a love affair with southwestern France and its prehistory for all of my adult life. I first visited the collapsed rock shelter of Abri Castanet, nine kilometers downstream from Lascaux Cave in the Vézère Valley of France, when I was a young graduate student some 33 years ago. At that time, I was doing thesis research on the geographic locations of Cro-Magnon living sites in southwestern France, seeking to understand the logic behind prehistoric choice of living places. Abri Castanet stuck in my mind for reasons both good and bad.

Some of the ancient beads unearthed at the site are displayed in a nearby museum. Credit: Larry Engel

The bad: There had been no excavations at Castanet since the 1920s and the site was in a terrible state of abandon, even serving as the garbage dump for the farmhouse above the site. As a young, idealistic archaeologist in 1976, this seemed to me to be a shocking state of affairs for a site that had yielded much of what was then the oldest known evidence for art and body ornaments.

The good: It was apparent to me that much of the site remained intact and unexcavated. Since the early excavations at Castanet had been done with rather crude, pre-modern excavation techniques, the fact that there remained substantial intact deposits meant that new excavations could someday provide a wealth of data on the precise dates of the early symbolic artifacts and on the context of their production and use more than 30,000 years ago. Was Castanet an ordinary living site…or something more special? What time of the year was it occupied? How exactly were the dozens of engraved and painted limestone blocks related to other human activities and living structures at the site? Were the hundreds of personal ornaments manufactured here or were they brought in by exchange only to be lost or abandoned on-site?

A number of the Abri Castanet finds are housed just up the road at the tiny Musée de Prehistoire du Site de Castel Merle. Credit: Larry Engel

In 1976, as I contemplated the desolation of the site, then obscured by a thick mat of moss, ivy, and decomposing debris, it did not even cross my mind that someday I would undertake decades of research here that would lead to discoveries shedding new light on the evolution of human society and symbol-use. I simply tucked away the fact of its intact deposits into some remote corner of my professional memory.

Who knew that in the 1980s I would become a leading researcher on the subject of Ice Age body ornamentation and that I would return to Castanet several times that decade to study the ornaments from the early twentieth century excavations? Those old collections left so many unanswered questions that, in 1994, I came back to Castanet to dig, hoping that I was right in thinking that it still had secrets to reveal about the ancient Cro-Magnons.

Abri Castanet kept up its part of the bargain. By the time Alan Alda and the Human Spark crew arrived at Castanet in the summer of 2008, I had already directed a Franco-American research team during nine seasons of unimaginably meticulous excavations, recovering even the dust and debris from bead-making, thus proving the existence of workshops for ornament production.

Our work at Castanet might have ended this year had not a major discovery occurred during the 2007 season when we discovered a one-ton fragment of the collapsed roof of the Castanet shelter. The roof had fallen (undoubtedly with an enormous wooompff) directly onto an ancient living surface bearing stone tools, fireplaces and animal bones. On July 9, 2007, we would discover that its undersurface, the former ceiling under which the site’s Ice Age occupants had lived, had been painted and engraved by them.

The Human Spark crew films the excavation team hard at work in the rock shelter. Credit: Maggie Villiger

At the moment of collapse, bits and pieces of animal bone from the living surface became stuck to the decorated ceiling. Six radiocarbon dates on these bone fragments provide dates of 32,400 years ago, making the Castanet decorated ceiling one of the three or four oldest examples of engraved/painted imagery on the planet. Better yet, much of the remainder of the collapsed ceiling, in direct contact with the living surface upon which the artists stood, is still in place. Over the next ten years, we plan to excavate and study more than 20 square meters of the ancient decorated ceiling and the artifactual evidence for human activities that took place under the decorated ceiling before its collapse.

It was great fun to share our work with Alan Alda, Graham Chedd and the Human Spark crew and to illustrate for them the hard-won knowledge of the past that comes from years of patience, persistence and teamwork. If there is a Human Spark II in ten years, come back to see us… We will still be there adding solid new bricks to the edifice of knowledge of the human past.

Archaeology is an exceedingly expensive endeavor and the Castanet project would not be possible without generous assistance from: United States National Science Foundation, the Direction des affaires culturelles de l’Aquitaine (French Ministry of Culture), the LSB Leakey Foundation, the Reed Foundation, the Institute for Ice Age Studies and New York University.

Veronica Waweru shares some of her recreated arrows with Alan as Larry Engel and Peter Miller capture the video and audio and Producer Graham Chedd looks on. Credit: Maggie Villiger

By Veronica Waweru

Ancient human inventions always engender debate among paleoanthropologists. Models are developed to explain the appearance and timing of new “novel” technologies or behavior. I am no different from these researchers and harbor a fascination with the origin of the bow and arrow. This technology is central to discussions on the hunting abilities of ancients. Were they not-too-smart creatures that scavenged leftovers from big cats, did they only hunt docile animals or were they proficient hunters who brought down dangerous animals? These debates often also include comparisons of Homo sapiens of the last 200,000 years to their Neanderthal contemporaries. Often, the discussion pivots on whether early Homo sapiens were better hunters than Neanderthals. The evidence cited by most researchers suggests that our cold-adapted relatives in Eurasia were not such adept hunters – what with their rodeo-rider-type injuries and their large spears that would force them to engage prey face to face. The most damning evidence for Neanderthals’ technological ineptitude is their extinction – at least for those who do not believe that they interbred with Homo sapiens. But that is a different debate altogether!

Veronica holds a stone point that dates to 100,000 years ago.

Stone armatures or points are amongst the most durable artifacts found in the archaeological record. These were used to arm the business end of knives, javelins, stabbing spears, atlatls and the bow and arrow. All of the organic elements of these implements dating back to 200,000 years ago have decomposed, of course. We are left with the stone tips to determine what weaponry system they were part of. Here we apply laws of physics and ballistics, take copious measurements of the stone tips and attempt to extract ancient blood serum and fats from their edges to make our cases. Then we cite evidence of indigenous people who still use spears and arrows to hunt.

My work focuses on finding evidence of the bow and arrow using stone points from Cartwright’s site, located on the Kinangop plateau in Kenya. I have used most methods employed by researchers in the field but also went ahead and had replicas of the prehistoric tips made and hafted onto arrow shafts. We then shot them at sides of pork and a complete goat carcass (very humanely dispatched and used for food afterward). The results indicated that in terms of distance traveled and penetration, some of the points worked well as “arrowheads.”

Veronica examines the arrows of a modern hunter in Kenya while the Human Spark camera captures their exchange. Credit: Maggie Villiger

To any hunter, putting distance between yourself and prey that might potentially fight back is important. Here, arrows have an advantage over spears. Weapons also need to deliver lethal blows, induce massive bleeding or cause damage to internal organs. Penetration depth is therefore important. In a nutshell, we have a lightweight projectile weapon dating to approximately 100,000 years ago in east Africa! One that can be transported for long distances, the head easily replaced, and the arrow shot from a variety of positions and potentially by a group of hunters, without alerting prey. Modern hunters often add a cocktail of poisons to the shafts of their arrows. These are derived from plants (such as the arrow poison tree) that have wide distribution in Africa. Did prehistoric hunters use arrows to deliver poisons to quarry? We may never know because poisons are unlikely to survive that long.

If arrows could be used effectively against large dangerous prey, why not against our enemies? Here the gore starts – coalitionary violence against members of our own species. What might prehistoric people fight over? Perhaps not oil or ideology but scarce food resources during dry climatic conditions brought on by glacial cycles. Would such a weapon, when used in tandem with poisons, not threaten the very survival of a group if people took to shooting each other over resources?

After showing that prehistoric stone tools were likely used with the bow and arrow, I am now investigating the implications of this invention. Many researchers have argued that human aggression has a genetic substrate. I suspect that cultural mechanisms would have evolved to protect members of a social group from each other. I am presently studying poison-tipped arrow use in interethnic violence in Kenya. This will give insights into lethal violence between members of an ethnic group and non-members. 100,000 years ago, long before Hammurabi’s law or the Ten Commandants were in place, ancients may have had an unwritten — albeit tempered — Second Amendment. Thou shall posses and use poison tipped projectiles, but only on outsiders.

Veronica became the center of attention at the Kariokor Market in Nairobi when she showed up with our film crew. Here a vendor exhibits the modern arrows he sells there. Caption: Maggie Villiger

My fascination with the gore and science of ancient projectiles and poisons, led me to join the Human Spark film crew in Kenya last summer. I did some background work to find people to interview about bows and arrows and poisons. Metal-tipped arrows for sale were easy to find. The poison sources and makers were more elusive. Do you want to kill a stray dog? A person? Why not try bewitching them? The best answer I got was that only very old men made poisons, but they lived “very far away” and may not to want talk to women or strangers. So when the Human Spark crew arrived, I had but one contact who made bows and arrows for sale and who failed to persuade his great uncle to speak about poisons. Our first shooting site was a local market in downtown Nairobi. The crew appeared very much at ease among the throngs of curious crowds and open sewers. My favorite part of the whole event was getting pulled over by local policemen on our way out of Nairobi. They are notorious for taking bribes, but one look at the huge camera and they let us go. I almost dared them to ask for a bribe.

Next summer, I will get a big dummy camera to scare away corrupt traffic police, and endure more rides through potholed dirt roads to coax recipes of poison cocktails from unwilling old men of the Kamba ethnic group. The curiosity is intense and unrelenting. I blame it on a primordial curse – The Human Spark!

Setting up. Note the lights in the upper corners of the picture. Credit: Larry Engel

The American Museum of Natural History is truly the icon of natural history museums. It sits majestically between Central Park West and Columbus Ave on the Upper West Side of New York City. I remember visiting it as a kid when my parents took my brother and me to the museum to see the dinosaurs and dioramas. It was an out-of-this-world experience and totally surreal. Cavernous halls, huge beasts, totem poles and canoes. Bones and more bones.

Its facade was used as the museum exterior in Howard Hawk’s great screwball comedy “Bringing up Baby” with Gary Grant and Katharine Hepburn. When I show the opening scenes of the film in my theory class at American University, I fondly remember walking up the museum’s grand steps and entering another world, far removed from the bustling streets of New York City just outside.

Unloading all the gear from our three vehicles. Credit: Larry Engel

Today, we’re here with Alan to pay a short but important visit to Ian Tattersall, one of the preeminent archeologists in the world. He’s a large man in physique and stature. And his office, lined with classic wood and glass cabinets holding ancient clues to our distant past, is cavernous. I expect Cary Grant to appear from behind a cabinet carrying a bone.

Gels, used to change the color of the light. Credit: Maggie Villiger

Although this is not the first scene that we’ve filmed, nor the first location, it may very well wind up as the first scene of the series. Because we have limited time to set up and a big space with which to work, producer Graham Chedd and I have decided to bring in a gaffer (the person who is responsible for setting lights on larger productions) to help light Ian’s office. We did a preliminary scout a couple of days before to determine what look we were after, what range we wanted to give Alan and Ian to move, then what lights we needed and how many people we’d need to get the job done.

So our local gaffer and I worked out a plan of action. On shoot day, he and his assistant brought a truck that came with lights, stands, stingers (extension cables – so-called because of obvious negative potentials), gels, dimmers, ladders, and a lot of other stuff. We parked underneath the museum and it took about an hour to move all our gear through the museum (being very careful not to damage any exhibits, including one on human origins that Ian had curated) and up to the office.

We had decided to not use a big window in the room as a light source because we didn’t want to fight changes in sunlight over the course of the day. I do sometimes use this natural light source as a key light (the main light of a scene), but usually I do that when I’m only at location briefly and the window is a north-facing one (giving generally even light over the course of our time there). We also wanted not to use lights that would produce too much heat or harsh shadows. We settled on a type of fluorescent light that is balanced for daylight (or film tungsten light) called Kinos. They come in different lengths and numbers of bulbs per fixture.

A cart of sandbags and apple crates – that is, weights and stepstools. Credit: Maggie Villiger

We ended up using about three or four banks of them along with a couple of harder-shadow lights. All were set high, some on tall stands secured with plenty of sandbags or propped up on top of the cabinets. It was crucial not to damage the facility or, obviously, any of the skeletons and other bones and artifacts that were stored there. It was also important to us that we lit the space so that Alan and Ian weren’t forced to stand immobile in one position but could move about the room organically. This would make their interaction more comfortable.

I really enjoyed this location because of the wonderful sense of history and evolution with skulls and re-constructions of heads from our ancestors all around the room.

A resident of Cayo Santiago takes in the scene. Photo by Larry Engel

By Larry Engel, Director of Photography

At the southeastern tip of Puerto Rico is a small island only a short boat ride from the mainland. We flew into San Juan, drove south through the mountains, down to the shore to meet the scientists with whom we would work the following morning. At the beach, families were enjoying the late afternoon sun and water. People were dancing in the parking lot. It was warm and pleasant. We could see Cayo Santiago about a half-mile offshore from the pier.

The island is home to a group of monkeys that were brought there in 1938 so North American researchers could better study primates without having to go to South America or Africa. One problem, though, was that in the early days of primate research, people didn’t have a solid grasp of habitat and dietary needs for their research animals. Even though it seemed as if Cayo Santiago was big enough to support a colony of rhesus macaques, it turns out that the vegetation and habitat area is not sufficient to support the 1,000 monkeys who currently live freely on the island. So there is a need to supplement that food, which does grow on the island, and two main feeding stations provide extra food for the monkeys. To get to the food, the monkeys have to open metal bins. The lids clang off-and-on throughout the day, and while we were filming this sound drove me nuts. An otherwise peaceful setting was constantly dotted with the clinging and clanging of what sounded like, at least to me, crazy garbage men at work.

We were warned that the monkeys could come over and try to bite us, but that we could fend them off with our own loud noises and a few displays of aggressiveness (for example, raising our arms high and waving them — sort of like what you might do if you were trying to get rescued). I thought that the camera would be a good defense, so I wasn’t too worried. But a couple of times during the day’s shoot, one of researchers would yell out a warning to the monkeys while I had my eye to the viewfinder.

We were also warned not to spend too much time under branches where monkeys were sitting. This was a somewhat difficult task for me as I would find a good location for a shot but then realize that I had positioned the tripod or myself directly beneath a monkey. The reason that you don’t want to hang out under a monkey on a branch is that they have a tendency to intentionally urinate on you – or worse! I wondered if I should put the rain cover on the camera but decided against it. We all paid close attention to what was going on above us throughout the day.

In order to get on the island we had to have tuberculosis tests and provide our negative results. This was to protect the monkeys, not us. Throughout the primate world, there is growing alarm over the transmission of human diseases to our cousins. They don’t have the exposure to our diseases, and that makes them susceptible to not only getting sick but dying from illnesses that are seemingly innocuous to us – like the common cold. Another precaution: we had to retreat to a caged hut to eat and drink. We couldn’t eat anything outdoors; it would be bad for both the monkeys and us. I liked the idea that we were the ones who had to be inside the cage looking out while the monkeys were on the outside looking in.

A monkey makes his approach toward the grape of the researcher with her back turned, presumably because it thinks it will be easier to steal from someone who isn’t looking. Photo by Larry Engel

We were there to film researcher Laurie Santos and her experiments that look at monkeys’ decision-making concerning thievery. We were hoping to capture it all on video – not an easy task with our additional crew members in attendance.

This monkey successfully snagged the grape from behind Laurie Santos’ back. Photo by Larry Engel

The way it works is that two people approach a monkey who is paying attention to them. They both do exactly the same thing: show the monkey a grape, put it onto a square piece of wood, and put the “plate” on the ground. A third person counts and calls out the moves so that each person does exactly the same thing at the same time. When the grapes are on the ground, one person turns her back to the monkey. The other person stays facing the monkey. Then, both are motionless. The monkey more often than not sneaks up on the person who is not looking and steals the grape.

We actually were able to film the experiment successfully and even photographed another one. It was amazing how fast the monkeys would make their decision to go for the grape… but each monkey would look up at the experimenter’s back all the way to the grape before hightailing it back to the bush with treat in hand. One monkey, however, didn’t really care who was aware or unaware of his action. It appears that he was a dominant male and really didn’t care who he took food from. He was, literally, king of the hill.

I really enjoy filming animals, especially primates. When I’m looking into the eyepiece, through the lens, most of my world disappears and I’m in their world. I don’t see us; I see them. I’m drawn into their world, I look into their eyes, and I wonder what they are thinking about me. Do they look at us and think that we look somewhat like them? Do they wonder what we’re thinking as I do about them? There is a connection, but also a divide. And I’m honored to film among researchers who are trying to bridge it so that we can understand them better and, ultimately, they us.

A Spark or an Ember?

By John J. Shea, Anthropology Department, Stony Brook University

John Shea with some of his stone age technology. Photo: Larry Engel

Filming The Human Spark with Alan Alda led me to question some of the assumptions we make about the evolution of human uniqueness – the metaphorical “spark” in the title of this series.  Most anthropologists assume that the qualities that made humans unique evolved recently and only among members of our species, Homo sapiens.  But what if this assumption is an accident of history?  Might the things we think make us unique actually be characteristics we share with other hominins who are now extinct?  A spark can be the beginning of a fire, but it can also be the last ember of a conflagration.  What if our spark is not the start of something new, but rather the culmination of a long-running evolutionary trend?

In evolution, only differences matter.  The differences between humans and our nearest primate relatives, the chimpanzees, are not subtle.  We differ in locomotion, in how we use tools, in our diets, in how we get along with one another.  In virtually every way anthropologists care to make comparisons, we differ more from chimpanzees than chimpanzees differ from other apes.  Genetic studies suggest these differences accumulated over nearly 6 million years.  If all one had to work with were comparisons of the morphology, genetics and behavior of living species, one could not help but conclude that we are special, that we humans have a “spark” that chimpanzees and other apes do not.

But we know there is a fossil record for human evolution, and it tells a very different story.  Humans evolved in the Pleistocene Epoch (2.5 Million to 12,500 years ago).  This was a momentous period in the evolution of life on Earth.  It was a great time to be a hominin.  The term hominin refers to the group of bipedal primates that includes humans.  Two million years ago there were at least three major groups of hominins, Australopithecus, Paranthropus, and Homo, all living in Africa.  Each of these groups comprised at least two and almost certainly more distinct species.  For much of the Pleistocene, there was more than one human-like species walking the Earth at any one point in time.  As recently as 40,000 years ago, there were at least three, Neandertals in Europe, Homo sapiens in Africa and Asia, and Homo floresiensis in Indonesia.  Today there is only one hominin species, us.

Being the sole remaining contestant of “Survivor: Pleistocene” influences our ideas about our “human spark” and about the nature of human uniqueness.  Our “human spark” looks special to us because we cannot compare it directly to those of our extinct hominin relatives.  The evolutionary gulf between living apes and us is a recent evolutionary condition.  If one takes extinct hominins into account, the gulf between humans and apes will appear not so wide, because it would be populated by countless ape and hominin species.  Each species would have had its own “spark,” its own uniquely evolved characteristics, and those characteristics would differ with evolutionary distance.  Species with a recent common ancestor would be more similar to one another.  Our “human spark” would be very similar to that of the Neandertals, less similar to that of Homo floresiensis, and very different from that of Australopithecus.  Our “human spark” would still differ from those of living apes, but along a complex continuum of ape and hominin variation.

What caused the reduction of species in the Genus Homo?  The simple answer is that we do not know, but we can venture some well-founded hypotheses.  Climate change and habitat loss almost certainly played a role, as they do in recent animal extinctions.  Many early hominin fossils (particularly australopithecus and paranthropus) are found in woodland habitats.  Such woodlands have been losing ground to grasslands for the last two million years.  Predators may have played a role.  The carnivores that preyed on australopithecines and paranthropines were mostly solitary felids (large cats like leopards).  The Pleistocene witnessed the evolution of large social carnivores, like lions and wolves.  These carnivores may have caused problems for some hominin species, either preying on them directly or out-competing them for access to meat and fat from large animal carcasses.  Bad luck may have played a role, as well.  Neandertals lived in some of the coldest habitats ever occupied by primates during a period of rapid, near chaotic climate change.  Their extinction, though tragic, is not particularly surprising.

Paleoanthropologists have been strangely reluctant to consider the role of competition among hominin species in the evolution of the Genus Homo.  Yet, competition is the engine that drives evolution.  In evolutionary competition, your most formidable rivals are those to whom you are most closely related.  Homo sapiens’ evolutionary success must have come at the expense of other hominin species, most likely those closely related to us.  One can see proof of this in a pattern that occurs in the fossil record.  In region after region, the first appearance date of Homo sapiens fossils is closely correlated with the last appearance dates of other hominin species.  There appear to have been some places where other species “held their ground:” Neandertals in southern Spain, Homo floresiensis in the forests of Indonesia, but these are exceptions, and in neither case is there clear and convincing evidence for long-term, face-to-face encounters between our species and other hominins.

This is why I am skeptical about arguments that early Homo sapiens killed off the Neandertals and other hominins.  It is not that I think they were necessarily good-natured.  Their moral sentiments probably varied widely, just as ours do.  Rather, I think they just did not encounter other hominin species often enough for the benefits of sustained conflict to exceed the risks and costs.

So, why did Homo sapiens survive and other hominins become extinct?  One key to our “human spark” is our uniquely broad ecological niche.  An ecological niche is the network of predator-prey relationships between one species and other species.  In evolutionary competition, generalists (species with a complex niche) always beat specialists (species with a simple one).  Homo sapiens is the ultimate generalist.  We sustain ourselves on animal prey ranging from snails to elephants, on birds, fish, and countless plant foods.  Much of this niche breadth reflects recent innovations, such as agriculture and pastoralism.  I am increasingly convinced that there was an earlier “revolution” in our ancestral human niche, one underwritten by the use of projectile weaponry.  Projectile weapons, such as the bow and arrow are niche-broadening tools.  The same bow that can launch an arrow at a fish or rodent can bring down an elephant, when it is tipped with poison.  Projectile weaponry is uniquely human and culturally universal.   We are the only species that uses projectile weaponry, and no human society has ever abandoned its use.

In seeking the origins of human uniqueness, I think it is absolutely crucial for archaeologists to work out when and where humans began using projectile weaponry to broaden their ecological niche.  Right now, evidence in the form of stone points similar to recent arrowheads is strongest in equatorial Africa, the region in which Homo sapiens first evolved.  The strongest such evidence dates to between 50,000 to 100,000 years ago, but as noted in the Human Spark, new discoveries will almost certainly push these dates back further.  I do not think that projectile technology alone explains human uniqueness.  Nothing in evolution is that simple.  Yet, projectile weaponry is an interesting piece of our human evolutionary puzzle that has not received the scientific attention it deserves.

Some academics look down at television programming as “merely” entertainment.  I disagree.  If you take public money for your education (as I did), and expend such funds in your research (as I do), you have a moral obligation share the fruits of your studies as broadly and effectively as possible.  Far more people will view the Human Spark than will ever listen to my academic lectures or read any of my scientific papers.  The most effective way to show how scientific research about human evolution matters is by working with people like Alan and his colleagues to create a thought-provoking program like the Human Spark.

Alan Alda and John Shea work on stone tools side by side. Photo: © Larry Engel 2008

How does your research relate to the idea of a “human spark?”

Describing human uniqueness as a “spark” suggests that what makes us unique as a species is, like fire, something that grows from small beginnings to something larger and more transformative. Most evolutionary changes start small. The risk of taking the spark metaphor too literally in human origins research is that it is exceedingly unlikely that our species’ uniqueness arose from just one small change. Nothing in evolution is that simple. A particular scientist may champion one factor or another as a prime mover in human evolution, but this has more to do with academic politics than it does with a realistic view of how evolution actually works. Programs like The Human Spark are good because they show the wide range of information we paleoanthropologists have to pull together to create testable hypotheses about the course of human evolution.

How did you become interested in paleoanthropology and eventually wind up at Stony Brook University?

When I was young, I read many books about ancient Greek, Roman, and Norse mythology. I was also interested in woodcraft – hiking, fishing, camping, and other “Boy Scout” kinds of things. These interests converged in studying archaeology at Boston University. At Harvard, I became especially interested in finding links between archaeology and physical anthropology.

John Shea shows off some replica spears to Alan Alda in front of the Human Spark film crew. Photo: Maggie Villiger

What you are working on these days?

I am currently researching the origins of projectile weaponry (bows and arrow, spearthrowers, etc.) by making and using replicas of these weapon systems. Projectile weapons are used by all known human societies and used only by Homo sapiens among all living animals. My research suggests projectile weaponry enabled our ancestors to create a broad, flexible, and stable ecological niche that gave them a competitive advantage over other hominin species.

Why is this kind of research important to pursue?

How we humans differ from other animals and from one another is the most important question in anthropology. It is, in essence, the question from which all other anthropological questions originate. If projectile weaponry played a significant role in our species’ origins and global dispersal, then we may have found one part of the answer to the “big question” of anthropology.

What are the wider-ranging implications of your projectile research?

If projectile weaponry is as ancient as my research suggests, then this implies that responsible weapon use is an important part of our evolutionary heritage. It has got our species through some tough times. I think it is important to preserve this ethic of responsibility. I strongly support the right to bear arms, provided the people who do so possess the same responsibility and intelligence about using them as our Ice Age ancestors did.

John and Alan try their hand at hunting with projectile technology – but their prey is a Styrofoam deer. Credit: © Larry Engel 2008

What’s it like actually doing the day-to-day work that leads to all the big ideas and theories?

Few big ideas actually occur when I am surveying, digging or working in the lab. My best ideas typically crop up when it is least convenient to write them down – while lecturing to students in class or while riding my mountain bike through the woods.

What do you think the future of your field might hold?

As we learn more about the earliest phases in the evolution of Homo sapiens, we are either going to find that their behavior was just as complex as ours or that it was organized fundamentally differently from ours. In either case, what we find is going to challenge people’s assumptions about human uniqueness.

What was it like working with the Human Spark film crew?

Television airtime is expensive. You have to make your point quickly and economically. A good producer, like Graham Chedd, helps you learn how to do this. Several times, I dashed back to my office to write down a new idea, or some particularly apt way of phrasing something that occurred to me while filming.

Also check out this interview clip of John Shea talking about The Human Spark and his contributions to the show.

It looks like “Bambi” will evade another spear, this one thrown by Alan Alda. Photo © Larry Engel 2008

We’re in the middle of a group of people sitting on the ground. They’re hitting rock against rock. Alan is among them. Flakes fly off from large chunks of black obsidian. They are all trying to make the perfect stone tool — a sharp-edged stone cutter that was used by early humans for hundreds of thousands of years in our past. We’re not in a terribly exotic location like Africa. No, we’re in the heart of Long Island, NY at Stony Brook, which is part of the State University of New York. John Shea is the group’s leader, a professor in experimental archeology. Alan has come to learn first-hand how early stone tools were made, and why making tools in the way that humans did deep in prehistory has so separated us from other tool-using and tool-making species.

I had to make sure that my lens was well-protected, so I put a clear UV filter in the matte box. This way, if a sharp flake hit the camera it would chip a $250 filter rather than a $25,000 lens. The flakes are harder than glass, and they’re sharp. In fact, surgeons use obsidian blades in some of the most delicate surgeries they perform.

Veronica Waweru sets Alan Alda up with replica bow and arrows. Photo: Maggie Villiger

We have a busy day ahead of us. First it’s the flaking. Then we head to the sports complex where we experiment with more sophisticated weaponry — spears and arrows. Being able to take down prey from a distance provides a great advantage over trying to attack it up close and personal. The move from hand axes to more sophisticated hunting tools (and techniques — including group, or shared, hunting) may have been one of those human sparks that we’re looking for. It takes more social interaction and trust to hunt together than to go it alone. It also indicates a move away from scavenging toward more aggressive hunting and larger prey.

Veronica Waweru, a Kenyan, is here on the ball field with us. The construction and use of arrows is her archaeological specialty. She’s especially interested in the contemporary and ancient use of poisons in conjunction with arrows. Arrows, she and Shea explain to Alan, are even more sophisticated than spears. They not only demand the construction of the weapon itself, but also of the launching device — the bow. This may have led to divisions of labor among the early toolmakers, perhaps another indicator of the human spark… more trust and social interaction.

In any case, everyone, including Alan, is taking aim at a Styrofoam deer that John plopped down in the middle of the field. No one is doing a very good job of hitting the target, and I’m trying not to laugh too hard and shake the camera when a spear does make its mark. Everyone takes several steps closer to the prey. No hits. Another few steps closer. Finally a few spears hit home, including one from Alan, who’s very pleased with his marksmanship.

With weapons and deer in hand, we finally head back to the classroom (after eating hand-delivered pizza in the lounge). There, John is preparing to demonstrate another example of early humans’ ability to make things.

We move the tables and chairs to the back of the room, hang a black backdrop, and put up a couple of lights so John appears more in limbo than in a classroom. I’m in very close to him with the camera. He had warned me that the flakes coming off the rock are extremely sharp and that I should wear gloves to protect my hands. I did for a while, but then after changing lenses for better macro (close-up) work, I didn’t bother putting the gloves back on. Big mistake.

I’m filming no more than a foot away from John and I feel a little touch on my left knuckle; I have my left hand out in front of the camera supporting the lens and focusing. Not thinking much about it, I keep filming until John stops working and looks at me. Peter Miller, our sound recordist and a good friend of mine, also looks down at me. I’m dripping nice deep-red blood all over my pants as I move to change the camera angle on John.

One small fleck has sliced my knuckle nearly to the bone. We scramble for the first-aid kit, clean the wound and bandage it up tight. Blood seeps through but eventually clots. The wound ends up healing fast and without a scar, something that John said would happen because it was such a clean cut. And I never even felt it.

John Shea displays his bead handiwork. Is this one piece of the human spark? Photo © Larry Engel 2008

Back to work, John is now working with a small stone tool with a pointy end to make an object that has little to do with hunting. He’s working with soapstone, a rather soft rock. He first takes the small piece of soapstone and whittles on one side, then the other, finally creating a tiny hole. Then he works around the hole, reducing the size of the stone until he’s made… a bead. He finishes his creation by staining it a deep red from a piece of ochre that he dissolves in a little bit of water.

As an experimental archeologist, Shea seeks to better understand our ancestors by discovering how ancient things were made and used. In struggling to manufacture primitive tools and artifacts, he learns to better understand the techniques, the raw materials and the labor needed for their creation and use. Beads have become something of a new passion for him and his peers – they indicate a capacity for art and symbolism and also that their makers had the time and labor to pursue the creation of objects not directly related to food and survival. They’ve recently been discovered in several new locations in Africa at sites that push the date for beadwork far deeper into our past.

As we’re about to wrap the day, we ask John what he thinks the human spark is. He answers that perhaps one spark was the creation of a hole in a small piece of stone.

When they aren’t distracted by unfamiliar camera crews, the chimps Lisa works are quite good at calmly working on computer games.

By Lisa A. Parr, Yerkes National Primate Research Center

It’s always a little nerve wracking when people come to visit the chimps. Despite the fact that the chimpanzees I study are extremely well-trained, follow simple verbal instructions, and would perform most of our tasks without the small amounts of sugar-free Kool-Aid that we give them as reinforcement (because they are fun), they are still powerful, wild animals with their own free will. You can almost never get a chimpanzee to do something it doesn’t want to do: they are too big, too strong, and almost certainly too smart. And if Murphy’s Law has anything to say about it, when you do want them to do something, you are definitely out of luck if there is a camera crew involved. Such is the situation when Alan Alda and the Human Spark filming crew recently visited my lab at the Yerkes National Primate Research Center in Atlanta, Georgia.

Lisa and Alan observe a chimp working on a facial expressions task. The animal is looking at computer-generated faces like the one on the screen beside them.

In my research on social cognition, I am interested in what kinds of information chimpanzees garner from faces. Can they tell different individual chimpanzees apart if presented only with their faces? Do they recognize different categories of facial expressions, and if so, how? Ultimately, my lab is interested in drawing parallels between human and chimpanzee facial expressions and the extent to which they may be involved in communicating about emotion.  To do this, we have trained six chimpanzees to discriminate images on a computer monitor by selecting those that match using a joystick-controlled cursor. We have shown that chimpanzees discriminate faces and facial expressions much like humans do, using the entire configuration of facial features, and particularly features related to the shape of the mouth.

While this might sound like it’s straight out of the movie Project X, the chimpanzees actually learn this task very quickly and perform extremely well, even when we make the tasks quite challenging. Well, that is to say on a typical day. On this day, however, two large male chimpanzees (that have been part of my research program for almost 15 years) were confronted by several unfamiliar men holding expensive video equipment.

Lisa Parr (right) and Alan Alda (center) attempt to work on a computer task with a distracted chimp as cameraman Peter Hoving films. Photo: Maggie Villiger

To compose the scene (the producers thought it was a good idea at the time), Alan and I were positioned directly in front of the 1 ¼ inch thick Plexiglas window that separates the chimpanzee portion of my testing room, where the chimpanzees have their own computer, from the human-tester portion of the room. We had unintentionally created what Alan later referred to as his “King Kong moment” (forgetting for now that King Kong was actually a gorilla).

The chimps were more interested in being tough guys in front of the film crew than doing their usual computer tasks.

You see, chimpanzees are extremely territorial in the wild. So, instead of sitting and diligently showing off their computer-skills, as they would on a regular day, these two chimpanzees did what any self-respecting male chimpanzee would do: try and intimidate the group of strangers with their characteristic bluff-display. Such a display consists of chimpanzees standing bipedally (on both legs), puffing out their hair (piloerection), swaying back and forth, charging at the offending parties, hooting and screaming loudly, and throwing any objects that are within reach. These displays are demonstrations of sheer power and, in the wild, males use them to reinforce their dominance, intimidate rivals, and aid in coalition formation. I’ve seen these displays so often that I sometimes forget how awesome they are, not to mention when there is only 1 ¼ inch of Plexiglas separation between us!

Needless to say, Alan and I survived, although the chimpanzees won this contest (again), and the cameraman’s skills prevailed as his nerves were tested holding the camera steady despite the large, blurry black figures jumping back and forth in his lens. So, for the rest of the afternoon, instead of working quietly on their tasks, the chimpanzees frolicked and played, occasionally returning to remind us of who was in charge, and Alan and I were finally able to discuss chimpanzees, facial expressions, and the challenges researchers are faced with when trying to understand cognitive abilities in other animals.

by Vicky Horner, Living Links Center, Emory University

To many people, the words “culture” and “chimpanzee” don’t seem to go together. In fact, apart from starting with the same letter, they seem to have little connection at all. It’s therefore always slightly awkward when I have to explain what I do for a living to someone I don’t know very well. When I tell them that I am a psychologist, but that I work with chimpanzees and study their cultural behavior, I get the distinct impression that some folks think perhaps it is me, and not the chimps, that needs a psychologist!

The looks of surprise and confusion come from the fact that for many people the notion of culture equates with the fine arts, a night at the opera, or a refined palate for expensive wine. The idea of a chimpanzee at the opera sipping on a nice glass of chardonnay is pretty comical, even to me. We can all think of lots of examples of cultural differences between groups of people, but actually defining it in biological terms is a little more difficult. Psychologists, anthropologists and biologists have been arguing about culture for decades, and although we still don’t agree, we are getting a little closer to a definition that keeps most people happy. In order to understand culture, and more importantly to understand the evolution of our own cultural abilities, we need to stop getting caught up in examples of our cultural behavior and focus more on how cultural differences develop in the first place. At the fundamental level, culture is simply a collection of learned behaviors that have been passed on from one generation to the next, such as using chopsticks or knives and forks. For many years culture has been regarded as the hallmark of our species, the ‘human spark’ that separates us from other animals. However, before we can make claims about our own uniqueness, we need to check for similar sparks in other animals, starting with our closest living relatives, the chimpanzees, with whom we share a common ancestor and about 99 percent of our DNA.

One of the Yerkes chimps uses a tool to extract a tasty treat from one of Vicky’s puzzle boxes.

A few years ago, a group of scientists working in Africa got together to compare the behavior of the chimpanzees at their field sites. What they found was rather surprising. At every site, the chimpanzees displayed a totally different pattern of behavior, such as how they use tools and weapons. These differences were not easily explained by differences in habitat or genetics. The scientists therefore thought that perhaps these differences represented chimpanzee cultures, and arose because each group had invented different solutions to similar problems (like dipping for ants with long sticks or short sticks), and that these behaviors were maintained over generations by learning from one another.

However, it is very difficult to study culture and learning in the forest because there are so many variables, so at the Living Links Center we study chimpanzee culture in a more controlled captive environment. We study two social groups of chimpanzees who live in large indoor-outdoor enclosures with climbing structures, grass and toys.  We train one chimpanzee in each group to act as an “inventor” who solves a food puzzle (like how to get the banana out of the box with a stick) in one of two different ways. We then track if and how each new behavior spreads within the groups. These studies are important because they show us that chimpanzees have the brains for culture; they can learn and maintain new behaviors accurately enough to support the reports of culture from the wild. I am not claiming that there is no difference between going out to a Chinese restaurant to practice your chopstick skills and staying home to fish for termites in the back yard, but the fundamental psychological mechanism and the evolutionary driving force behind the two is the same.

Alan tries his hand at a puzzle box, though he’s not quite as motivated as a typical chimp to extract the M&M.

So what does all this mean for the human spark? To me there is no single spark that separates us from chimpanzees; we are intricately connected by our common ancestry. The differences between us arise from thousands of tiny differences in the frequency and contexts in which we do things. For example, we imitate one another constantly; chimpanzees imitate each other sometimes. We take other people’s perspectives on situations frequently; chimpanzees take another’s perspective sometimes. We empathize frequently, they empathize in some contexts. It is all of these little tweaks here and there that make up the human spark.

On a final note, I’d like to emphasize the importance of not falling into the trap of thinking that we are the ultimate and desirable endpoint of evolution. Chimpanzees and humans have both been evolving form our common ancestor for the last 5 million years. They may not be at the opera, but chimpanzee culture is remarkable in comparison to other species. We also have a habit of measuring their abilities against our own human checklist in the quest for the human spark. But what would happen if we measured ourselves on a chimpanzee checklist; would we find a “chimpanzee spark”? How do you measure up to this five-year-old chimpanzee?