Tag Archives: National Geographic documentary

The Great Human Race: How to survive

The Great Human Race is a new production of National Geographic, in three parts. I recently viewed the first episode, “Dawn” which comes with this description:

All people can trace their roots to the savanna of East Africa, the home of one of the first members of the human species — Homo habilis. Archaeologist Bill Schindler and survival instructor Cat Bigney face what early man did as they work together to survive in the wild savanna just as these primitive people did 2.6 million years ago — without any weapons or fire. But they soon find that living like our ancestors is harder than they expected.

Great Human Race premieres Monday, February 1, at 10/9c on National Geographic Channel.

Photo at the top of the post: NG Studios

NGS has asked me to participate in a roundtable (here is the link to the roundtable) focusing on this documentary, specifically addressing this question:


Do you think that experts today can accurately replicate the challenges that Homo habilis faced thousands of years ago? And do you think that experts today could survive and thrive as Homo habilis did?

This is very much my area, and I’m glad to contribute to the discussion. The short answer is, of course, no, this is too hard. But, we can try and in so doing, we can develop some interesting thinking about early human evolution.

My contribution to the conversation centers on two rules of being a human hunter gatherer. Homo habilis was not, of course, a human, but we assume that this early hominin had some incipient human traits, further developed with early Homo erectus/ergaster. The two rules of being a human hunter gatherer refer to important aspects of living off the land that my research indicates apply to modern humans living without agriculture or animal husbandry as a source of food. I don’t know if these rules applied to earlier hominins or not … that is the $64,000 dollar question.

Rule 1: If you don’t know where it is, you are not likely to find it.

Much of the story in the first episode of The Great Human Race has to do with the two scantily clad protagonists, a professional survivalist of sorts and an “experimental archaeology” expert, set lose in the African Savanna to see what would happen, searching for various resources. I won’t give you a spoiler, but the episode ends with their discovery of one of the most important resources they need to survive, with that discovery realized in a very spectacular way.

I spent a lot of time in the 1980s and early 1990s living with, and studying the foraging patterns of, the Efe Pygmy foragers of the Ituri Forest, Zaire (now Congo). One of the things I discovered and documented is the simple fact that most of the resources they use are not really found by them, as though they had no idea where they might be. They already know where most of the stuff they can eat either will be, or are likely to be.

Bot men and women gather plant resources, but this is more of a woman’s job. In most cases, the more important plant resources are well known fruiting trees or concentrations of trees, or patches of wild yams that are frequently exploited. Women catch fish in streams that they have fished repeatedly before. This involves damming the stream at two points and removing the water from between the dams so the fish are easy to harvest.

Men seasonally hunt honey, and much of the honey is taken from trees they have exploited in the past, and check on a regular basis to see if the bees have settled in that cavity again. They do occasionally cut down a honey tree, but this is fairly rare (it is very hard work).

Even hunting, which one might assume is somewhat random, is done with a great deal of expectation based on knowledge. One type of hunting (not the most revered but among the most predictable) is to take porcupines or other small mammals from cavernous areas beneath rock piles that are found here and there across the landscape. If you find a rock pile and try to get at the animals hiding in it, even with the use of dogs, the animals can easily escape as they have many hidden exists. But if you return to the same rock pile repeatedly, you know where many of these escape routes are and can block them with wood or stone. A repeatedly used rock pile can be exploited with a high degree of confidence in success.

One of the most productive methods of hunting is the ambush. A well known tree that produces a fruit eaten by small ground mammals such as duikers is identified as currently producing the bait. A nearby tree which is climbable is used as a hide, where the Efe man waits for his prey, shooting it from the tree. The Efe almost always camp in locations that were previously used as camps, so at any given location where they are living, any of the men can easily point out the location of excellent ambush sites, rock piles, and nearby potential honey spots, and the women, and some of the men, can easily point out the locations of nearby fruit trees or yam patches.

There is uncertainty as to what resource will pay off, and not every resource is so easily predicted, but most of the wild foods the Efe gather and hunt are exploitable because of this knowledge.

The information is probably shared among people in a group, but remarkably little conversation centers on this topic. You don’t hear Efe talking about the location of this or that resource more than you hear, say, Americans talking about the locations of this or that grocery story. Certainly, such things are part of the normal conversation but do not make up a large percentage of it.

Rule 2: If you are doing it right, the use of a given instance of a resource can increase its future return.

This is probably a more important finding than that related to the first rule, and is rather counterintuitive. If the Efe use a resource, they will quickly use it up. This is one of the main reasons they move frequently from camp to camp over the year. But, the value of that resource, both the likelihood that it will produce something, and the abundance it produces, is enhanced by their very use of it.

I’ve already implied a couple of examples. If you block off a few exit ways on a rock pile, you don’t unblock them when you are done. Those escape routes may remain blocked between uses. If you add to your ambush trees a blind to sit on (usually just a few sticks tied on here and there) or modify the tree to make it easier to climb, these modifications may make the use of that ambush spot easier in the future, allowing you to climb and sit in the tree more quickly, more quietly, and more comfortably. Efe will also remove branches that interfere with their view and their shot.

Often, after an Efe man has finished taking the honey and comb out of a bee nest way up in some tree, he will spend a few more minutes making the cavity the bees had nested in larger. This may increase the amount of honey that can be fit into that cavity the next honey season.

When Efe women harvest yams, they tend to keep the “head” of the yam, attached to the above ground vine, intact, and rebury it. The space where they took the yam out will then be filled, with a little luck, with more yam months later.

As the Efe walk along the trails they habitually use to get around in the forest, they maintain the trails to keep them open and passable. it takes an Efe twice as long to traverse a given distance of forest without a trail as with a trail. This is a huge long term enhancement in the return of foraging.

As the Efe walk along a trail, they often grab up fruits from trees along the way. They eat the fruit as they walk, or stop at a resting place and eat it there. I documented five species of fruit tree where the Efe spit out or otherwise discard the seed of the fruit. This process of dispersal, well known to plant ecologists, enhances the number of those fruit trees along these trails, roughly doubling the abundance of these seasonally consumed fruits.

And there’s more, I won’t bore you with now. Much of the energy the Efe put into foraging enhances future return, including the development and maintenance of the basic knowledge of where various resources are.

There is some evidence that chimps do something like this as well. Chimps are probably primary dispersers of some of the fuits they exploit, almost certainly enhancing the abundance of that type of tree or plant. Where chimps use nutting stones (this is rare, but there are some groups that do this), they seem to keep track of the where the stones were left, so finding this rare object is much more efficient.

Given that chimps use prior knowledge and enhancement a little, and human foragers are capable of using these two “rules” a lot, I would assume that some of this would have been going on with Homo habilis.

I should mention that the observations I’ve made with the Efe have since been made among other groups of foragers. This seems to be a general pattern among African tropical and subtropical foragers, and possibly beyond. If you don’t already know where something is, you are not likely to find it. And, once a resource is exploited, foragers are often likely to enhance its future value. The emergence of those two features of modern human foraging must have been part of the hominin evolutionary story.

Aging: Even Opie. An evolutionary perspective

I’m not going to say that Ron Howard is old or anything, but he isn’t Opie any more. (And, in fact, it has been fascinating and inspiring to watch his career, by the way.) Anyway, Howard produced a new documentary with National Geographic called “Breakthrough: The Age of Aging, which premieres Sunday, November 29 at 9 pm et on National Geographic Channel. And, pursuant to this, National Geographic’s web site is sponsoring a Roundtable on the topic. The roundtable addresses the question, “By treating aging as a disease are we just prolonging the inevitable or can we change the course of our lives?”

The short answer to this is, I’m not really sure, but I think it is helpful to put aging, and changes in human patterns of aging, in a broader anthropological and evolutionary perspective.

LOS ANGELES - Priya Balasubramanian studies the science of aging.??(photo credit:  Asylum Entertainment)
LOS ANGELES – Priya Balasubramanian studies the science of aging.??(photo credit: Asylum Entertainment)
People have long lived long, even hunter gatherers in the Stone Age, as to modern hunter gatherers. In fact, hunter gatherers may have had longer and healthier lives than some of their errand cousins who went and invented agriculture and animal husbandry. In some cases we know from archaeology that populations engaged in early experiments with agriculture experienced dramatic decreases in overall health, and presumably, life span. This may have been a combination of larger groups sharing more diseases, unsanitary conditions developing in a more settled lifestyle, and a diet based on a smaller range of foods one ends up when casting off the foraging way of life. Eventually, in regions where this has been observed, things got better, either as a result of cultural adaptation or genetic changes.

When we look into the past, it is too easy to compress our ancestry into a caricature of primitive humanity, and based that conception on the wrong model. For example, it is said that “people were shorter back then.” Often, that is true, but the shorter people were actually poor urban dwellers in late medieval European settlements where diet was poor and disease demanded more energy of the immune system than average, so growth was sacrificed. If we look at pre-agricultural foraging populations, we often see relatively tall people. This is a bit enigmatic because so many modern forager groups are short statured. The explanation for that is probably that forager groups who are still around today, or have been extant over the last century or so, eek out their existence in relatively marginal habitats, the better parts of the landscape taken over by farmers and herders.

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See: โ€œIf this was the Stone Age, Iโ€™d be dead by nowโ€
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So, we should expect that prehistoric lifespan varied across time and space, and as I noted, there were probably always elderly people, but just not too many of them, compared to today. It has become axiomatic to note in modern day conversations that many of our diseases, in the West, are “diseases of civilization.” This is a combination of health effects, but one of the most important is the lack of disease of the past because they have been addressed, at least for now, at least for a subset of the human population. Antibiotics alone probably allow a much larger proportion of the human population to survive long enough to experience age-related disease.

A good part of Howard’s documentary is about the science of aging. We want our scientists to figure out how to beat aging, or at least, slow it down. But this is not easy. Humans are primates, and primates are mammals. The very earliest mammals probably evolved to die young. That seems counterintuitive but it really isn’t. Life History Theory predicts that organisms will be selected to produce some sort of balance (or bias, imbalance) of three major energy shunting systems: growth, maintenance (including the immune system), and reproduction. Humans reproduce slowly, producing one (or two) offspring at a time, and putting a lot of effort into each one. This goes along with a long lifespan, because in order to produce a small number of high-quality offspring one must take some time. This, however, places additional demands on the immune system. In order to keep up with evolving microbes and the overall ravages of time, we need to spend a fair amount of effort on keeping from being too sick. And, we happen to be large, for a primate. That probably relates to predator pressure and a few other factors. So while we are selected to live a long time compared to the average primate (and certainly, the average mammal) we can only go just so far.

But perhaps more importantly, we (humans, and to a somewhat lesser extent, primates in general) are modified versions of mammals, and there are indications that mammals were never originally designed (by natural selection) to live long lives. Early mammals were probably small, and small goes along with a short lifespan in the mammalian world. Remember, those early mammals were living along side dinosaurs! (There were large early mammals but modern mammals, including all the more recent large one, probably evolved from a subset of them that were on the small side.) In a world where the smallest dinosaurs were larger than the largest mammals (or close to that) mammals were probably more often prey than predator. The best strategy if the most likely cause of death is being scarfed up by something larger is to live fast, have one or two litters of offspring, and do the whole “circle of life” thing really fast.

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See: How Long Is A Human Generation?
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One strong piece of evidence that a live fast and die young strategy applied to early mammals is the fact that mammal females are born already containing all the egg cells they will ever produce. This is the primary determinant of reproductive lifespan for human females. Organisms that are born ready to reproduce tend to have that strategy of rapid early reproduction followed by an early death. One of the more extreme examples of this is aphids. Aphids have two modes of reproduction, but in one of them, female aphids are born gravid. While human females are not born pregnant, they are born with the eggs ready to go.

Not only have humans (following the primate lead) extended their lifespan and slowed down their reproduction, but they ave added, apparently, another phase of life: Post reproductive. Human females in foraging societies around the world are productive members of their families after they have stopped being fertile. This seems to not make sense from a Darwinian perspective. Why not just keep reproducing until you die? Probably for two reasons. First, they can’t, because human lifespans are already extended to the limit of our phyolgeneticaly constrained abilities. Second, that post-reproductive period probably enhances Darwinian fitness. Studies have shown that elder women in foraging societies contribute significantly to the health and wellbeing of their own children’s offspring. Grandmothers are an adaptation!