Celebrating 20 Years of Tracker Evaluations!

20 years JPG small

To celebrate 20 years of CyberTracker Tracker Evaluations, initiated in 1994, we organised a CyberTracker meeting where evaluators were able to engage in critical discussion and peer review. Peer review is essential to maintain standards, especially as the network of CyberTracker evaluators continue to grow. Only by testing each other and engaging in critical discussion of evaluation principles, protocols and the interpretation of tracks & signs in the field is it possible to ensure that we all maintain the same standards.

We also discussed the creation of The Tracker Association, which will be based in South Africa, but will be open to all trackers worldwide. In addition to qualified trackers, who will be full members, we will also welcome any tracker who is working towards becoming a qualified tracker. While CyberTracker Conservation is a Public Benefit Organisation whose mission includes maintaining tracker standards through tracker certificates, CyberTracker is not a membership-based organisation. We therefore need a membership-based Tracker Association which can represent and promote the interests of trackers.

It was also great to simply have everyone together around a camp fire, relaxing and telling stories. Shani Preller suggested that the Tracker Association logo should be a camp fire, representing the tracker community. The art of tracking and the making of fire are perhaps the most ancient human traditions.

We are planning to make this an annual event, something that will help to strengthen and grow CyberTracker evaluations into the future.

The CyberTracker meeting was attended by Wilson Masia, Juan Pinto, Adriaan Louw, Lucas Mathonsi, Alan Yeowart, Lee Gutteridge, Mark Stavrakis, Taryn Ingram-Gillson, Shani Preller, Deirdre Opie, Kersey Lawrence, James Steyn and Louis Liebenberg.

CyberTracker used in Research on Endangered Bottlenose Dolphin of New Zealand

Sarah Dwyer, Gabriela Tezanos-Pinto, Ingrid Visser, Matthew Pawley, Anna Meissner, Jo Berghan and Karen Stockin have just published a paper on “Overlooking a potential hotspot at Great Barrier Island for the nationally endangered bottlenose dolphin of New Zealand” in the journal Endangered Species Research, Vol. 25:97-114, 2014.

bottlenose

ABSTRACT: Conservation initiatives are typically constrained by economic circumstances, a factor certainly true for marine mammal conservation in New Zealand. Most research in this field has been conducted following concerns over anthropogenic impacts on populations and has therefore been funded and/or driven by stakeholder interest. Bottlenose dolphins Tursiops truncatus are classified as ‘Nationally Endangered’ in New Zealand waters. Here, we present the first study on occurrence, site fidelity and abundance of this species off Great Barrier Island (GBI), a previously overlooked region within the home range of the North Island population. Dedicated boat-based photo-identification surveys were conducted monthly from 2011−2013, resulting in 1412 sighting records of 154 individuals. Dolphins were recorded during all months of the year, with a higher probability of encounter in deeper waters during summer and shallower waters during winter and spring. Group sizes (median = 35, mean = 36) were higher than previously reported for this population in other regions. Individual re-sighting patterns were variable; however, overall site fidelity was high (mean monthly sighting rate = 0.33). A Robust Design approach resulted in seasonal fluctuations in abundance and temporary emigration. Based on a super-population estimate, 171 dolphins (CI = 162−180) visited the area during 2011−2013. Our data suggest that GBI is a potential hotspot for bottlenose dolphins of the North Island population rather than a corridor to reach other destinations. We highlight the need for researchers, managers and funding agencies to consider the entire range of a population when conducting or funding research.

Tracking Science: The Origin of Scientific Thinking in Our Paleolithic Ancestors

By Louis Liebenberg

Skeptic Magazine, Volume 18, Number 3, 2013

Karoha1

There is a paradox in human evolution: It was once assumed not only that rational science originated with the ancient Greek philosophic schools, but that the belief systems of prehistoric hunter-gatherers were dominated by superstitions and irrational beliefs. If this was the case, then how did the human mind evolve the ability to do scientific reasoning if scientific reasoning was not required for hunter-gather subsistence?

A similar (albeit broader) paradox led the 19th century naturalist Alfred Russel Wallace to conclude that the human brain could not be the product of undirected evolution because “Natural selection could only have endowed savage man with a brain a few degrees superior to that of an ape, whereas he actually possesses one very little inferior to that of a philosopher” (1). The 20th century anthropologist Sherwood Washburn reframed the paradox when he pointed out that the same brain that has been adapted for the needs of hunter-gatherer subsistence today deals with the subtleties of modern mathematics and physics (2). More recently, the psychologist Steven Pinker has noted that Wallace’s paradox of the apparent evolutionary uselessness of human intelligence is a central problem of psychology, biology, and the scientific worldview (3), while the biologist Edward O. Wilson regards it as “the great mystery of human evolution: how to account for calculus and Mozart” (4).

This apparent paradox may be resolved if it is assumed that at least some of the first anatomically modern hunter-gatherers were capable of scientific reasoning, and that the intellectual requirements of modern science were, at least among the most intelligent members of hunter-gatherer bands, a necessity for the survival of hunter-gatherer societies. The first creative science, practiced by possibly some of the earliest members of Homo sapiens who had modern brains and intellects, may have been the tracking of game animals. Tracking is a science that fundamentally requires the same intellectual abilities as a modern science like physics (5). (With “modern hunter-gatherers” and “modern intellects,” the term “modern” is used in the archaeological sense of the word, as when archaeologists and anthropologists refer to “anatomically modern humans” to mean our species. With “modern science” and “modern physics” the term “modern” refers to science and physics practiced during and since the 20th century.)

In the early 1980s I studied physics, mathematics and applied mathematics at the University of Cape Town. While doing a course in history and philosophy of science, I became fascinated by this paradox in human evolution. I had an intuitive gut feeling that the art of tracking may have been the origin of science. I dropped out of university to do my own independent research and in 1990 published my first book, The Art of Tracking: The Origin of Science (6). To do this research I had to become a tracker and spent long periods tracking with the Kalahari Bushmen. Since 1990 I focused on developing tracking into a modern science in order to create jobs for trackers, thereby preventing tracking from dying out.

The Art of Tracking

In easy tracking terrain, trackers may follow a trail simply by looking for one sign after the other, but in difficult terrain this can become so time-consuming that they may never catch up with their quarry. Instead of looking for one sign at a time, the trackers place themselves in the position of their quarry in order to anticipate the route it may have taken. They then decide in advance where they can expect to find signs, instead of wasting time looking for them. To reconstruct an animal’s activities, specific actions and movements must be seen in the context of the animal’s whole environment at specific times and places.

!Nam!kabe Molote of Lone Tree in the central Kalahari, Botswana, was one of the last of the traditional !Xõ Bushman master trackers who grew up hunting with the bow-and-arrow in a nomadic hunter-gatherer band. When he died in 1995, an invaluable store of indigenous knowledge was irretrievably lost. At that stage my own tracking skills were not advanced enough to fully appreciate the depth and subtlety of his tracking expertise. We may never know how good the last generation of traditional master trackers was.

Looking at the tracks of a solitary wildebeest of the previous evening, !Nam!kabe pointed out evidence of trampling, which indicated that the animal had slept at that spot. He explained that the tracks facing away from the sleeping place had been made early that morning and was therefore relatively fresh. The tracks then followed a straight course, indicating that the animal was on its way to a specific destination. After a while, !Nam!kabe started to investigate several sets of footprints in a particular area. He pointed out that these footprints all belonged to the same animal, but were made during previous days. He explained that that particular area was the feeding ground of that specific wildebeest. Since it was, by that time, about midday, it could be expected that the wildebeest may be resting in the shade in the near vicinity. He then followed up the fresh tracks, moving stealthily as the footprints became very fresh, until he spotted the animal in the shade of a tree, not very far from the area that he identified as its feeding ground.

One afternoon I went with !Nam!kabe to hunt a steenbok or a duiker. About two hundred meters from our camp !Nam!kabe shouted “lion!,” and a lioness jumped up in front of us, bounding off into the bush. Shouting to chase away any other lions that may be hidden in the bush, !Nam!kabe and I went to look at her tracks to see what she was doing there. As he studied the tracks, !Nam!kabe explained: “The lioness lay here, jumped up and ran away… this is a large female… she lay here and saw us coming and was afraid of us. We found her here near our camp… she stays here… we must follow her tracks and see if she killed an animal, then we can chase her away and take her meat.” But as we followed her tracks it was clear that she had not killed anything. “This lioness is here with us… don’t think that she ran away… she stalks us here in the thick bush.”

When we returned to our camp, the younger hunters decided to track the lioness. We set out with !Nam!kabe, his son !Nate, Kayate and Boroh//xao, armed with spears and throwing sticks. We could see from her tracks that she circled downwind to look at !Nam!kabe and myself as we were studying her tracks. Kayate said that we must follow her tracks and shout at her to chase her away, because she is too close to our camp.

That night, as we sat around the fire, they told stories of tracking lions and encounters with lions, times when they had to sleep in trees. And once in a while, !Nam!kabe would feel a burning sensation under his armpits and say that the lioness must be near our camp, stalking us from the downwind side. Then they would shout, banging on pots and throw sticks into the dark, downwind from us where they thought the lioness might be. This was repeated a number of times through the night until the dawn finally broke.

The next morning we went out to track the lioness to see what she was up to during the night. We found the place where she lay down until sunset. From there she got up and circled downwind of our camp, coming towards our camp. But as she came near our camp, she stopped. !Nate pointed at her tracks: “She stood here and heard us making a noise – these are the hind feet and here are the front feet… as she stood and listened, she thought to herself: ‘if I go there those people will kill me… if I do not go back I will die here tonight…’ then she turned around and went back to where she came from.”

We then followed her tracks to see where she was going. It was important to see how far she had gone and whether she had left the area or not. We found the place where she had slept for the night. We followed her tracks for most of the day, until we were satisfied that the lioness had moved out of the area and was no longer a threat to us.

The interpretation of the wildebeest and lion tracks was based not on the evidence of the tracks alone, but also on the trackers’ knowledge of animal behavior, on the context of the tracks in the environment, and on the time of the day. Since tracks may be partly obliterated or difficult to see, they may only exhibit partial evidence, so the reconstruction of these animals’ activities must be based on creative hypotheses. To interpret the footprints, trackers must use their imagination to visualize what the animal was doing to create such markings. Such a reconstruction will contain more information than is evident from the tracks, and will therefore be partly factual and partly hypothetical. As new factual information is gathered in the process of tracking, hypotheses may have to be revised or substituted by better ones. A hypothetical reconstruction of the animal’s behaviors may enable trackers to anticipate and predict the animal’s movements. These predictions provide ongoing testing of the hypotheses.

Novel Predictions in Tracking

Perhaps the most significant feature of creative science is that a hypothesis may enable the scientist to predict novel facts that would not otherwise have been known (7).

A simple example of how scientific reasoning may result in the prediction of novel facts in tracking is illustrated by a set of caracal (wildcat) tracks I found at Cape Point near Cape Town. Looking at the tracks I could visualize how the caracal was walking when it turned and pounced towards the left, twisted around and jumped back towards the right. There were no signs or tracks of the animal it was pouncing at. Initially I thought of two explanations. At first I thought it could not have pounced at a bird, because it pounced twice, and if the bird flew away, why would it pounce a second time? So I thought the fact that it pounced twice indicated that a mouse ran from the first pounce landing position to the second pounce landing position. But there were no sign of mouse tracks, so I thought that maybe the wet sand was hard enough that the mouse tracks did not show, or that instead of a mouse it was perhaps a tiny shrew. But neither hypothesis made me feel confident that it was the right explanation, leaving me feeling uneasy—it was a bit of a mystery to me.

The next morning I thought of a novel solution that was the result of two things that made me feel uneasy: first, I could not find any sign of mouse tracks, yet even the smallest mouse should have left faint signs of its sharp claws digging into the sand as it tried to get away from the caracal; second, the second time the caracal jumped (after twisting around), the bounding gait footprints left deep impressions, yet the stride length to the point where it landed was very short.

What I think must have happened is that it tried to pounce on a small bird sitting on the ground. The bird flew up in the direction of the second set of “pounce tracks,” so the caracal twisted around and leapt straight up into the air to catch the bird in mid-air. This would explain why the bounding tracks for the second leap left deep imprints (its feet was pushing down into the ground, not backwards) and why the stride length was so short (it went straight up and down). It would also explain why I could not find any mouse tracks or any other tracks. The tracks of the little bird, where it was sitting, would have been obliterated by the tracks of the caracal when it tried to pounce on it the first time.

I did not initially think of this explanation because at the time I did not know that a caracal could leap up and catch a bird in mid-air. In terms of my own experience at the time, this was a new behavior that I did not know of. As with any set of data that creates a puzzle that does not fit your preconceived expectations, your subconscious needs to work on it to create a new hypothesis; in other words, I had to “sleep on it” before thinking of a solution the next morning, resulting in an “aha moment.” In mathematics and science, the creation of a hypothesis often requires a subconscious period of incubation preceding a sudden illumination (8). Since the caracal is nocturnal, it is unlikely that I would ever observe this activity. However, creating a hypothetical explanation of the tracks enabled me to predict a novel fact about the caracal’s behavior.

The Logic of Science

Empirical knowledge is knowledge based on inductive-deductive reasoning, and “creative science” is knowledge based on hypothetico-deductive reasoning. Let us look at a simple, every-day example that everyone can relate to.

An example of inductive-deductive reasoning would be: Based on past experience, we know that the sun always comes up in the east in the morning. Therefore we can predict that the sun will come up in the east tomorrow morning. We use induction to make a generalization (the sun always comes up in the east), which we then use to deduce a prediction (therefore the sun will come up in the east tomorrow). Inductive-deductive reasoning does not explain why the sun comes up in the east every morning and cannot make novel predictions.

An example of hypothetico-deductive reasoning would be: A philosopher living in ancient Greece may have come up with a hypothesis that the sun appears to come up in the east every morning because the Earth rotates around its axis. The philosopher would then have been able to predict that the sun will always come up in the east every morning. Hypothetico-deductive reasoning explains why the sun comes up in the east every morning. Furthermore, this hypothesis would have enabled the philosopher to make a novel prediction—if you travel to the North Pole the sun will not appear to come up every morning.

We can now look at how the logic of science connects tracking and modern science.

Inductive-Deductive Reasoning

An example of inductive-deductive reasoning in tracking would be the way tracks are identified as that of an animal belonging to a particular species, such as the porcupine. Footprints may vary according to the softness or hardness of the ground, so we need to look for the characteristics which different footprints have in common.

The inductive stage of the argument may be as follows: all porcupines that have been observed produced tracks which had certain characteristics, and no porcupines have been observed to produce tracks that did not have those characteristics. We therefore assume that all porcupines leave tracks which have those specific characteristics. Furthermore, no other animals have been observed to leave tracks which had exactly the same characteristics. We therefore assume that only porcupines leave tracks which have those specific characteristics.

The deductive stage of the argument would then be as follows: we assume that all porcupines and only porcupines leave tracks which have specific characteristics. We conclude, therefore, that any particular track observed to have those specific characteristics would have been made by a porcupine.

In an inductive argument by simple enumeration, the premises and conclusions contain the same descriptive terms (9). It is therefore simply a process of empirical generalization, which does not lead to progress in science because they may only lead to the discovery of facts similar to those already known (7).
Inductive-deductive reasoning is based on direct observations and ordinarily recognizes apparent regularities in nature. Inductive empirical knowledge, therefore, is based on a trial-and-error accumulation of facts and generalizations derived by simple enumeration of instances. It does not explain observations and cannot result in the prediction of novel facts. It can only predict particular observations similar to those that have been observed in the past. Predictions are therefore simply based on experience.

Hypothetico-Deductive Reasoning

In contrast to inductive-deductive reasoning, hypothetico-deductive reasoning involves the explanation of observations in terms of hypothetical causes. The hypotheses may be used as premises in conjunction with initial conditions from which certain implications may be deduced. Some of the implications deduced in such a way may include novel predictions. Hypothetico-deductive reasoning in creative science is an exploratory dialogue between the imaginative and the critical, which alternate and interact. A hypothesis is formed by a process that is not illogical but non-logical, i.e. outside logic. But once a hypothesis has been formed it can be exposed to criticism (10).

A characteristic feature of a theoretical science is that it explains the visible world by a postulated invisible world. In physics, for example, visible matter is explained by hypotheses about an invisible structure that is too small to be seen (11). Similarly, in the art of tracking, visible tracks and signs are explained in terms of invisible activities. A sympathetic understanding of animal behavior enables the tracker to visualize what the animal may have been doing in order to create hypotheses that explain how visible signs were made and how they are connected. Visible signs are therefore connected by invisible processes. These postulated connections are inventions of the tracker’s imagination. Although these hypothetical connections cannot be seen, the conclusions that can be deduced from them enable the tracker to anticipate and predict visible signs.

A theoretical science such as physics is analogous to tracking in the sense that observable properties of the visible world may be regarded as signs of invisible structures or processes. The force of gravity (in Newton’s theory), or the gravitational field (in Einstein’s theory), or more recently the Higgs Boson, cannot actually be seen. Its postulated existence is only indicated by observable effects on bodies similar to those that such a force (or field) would have on bodies. Nuclear particles cannot be seen. Physicists can only see signs, such as “particle tracks,” that correspond to those that would be made by hypothetical particles.

Systematic and Speculative Tracking

We may now make the link between tracking and the origin of scientific reasoning through two fundamentally different types of tracking—systematic tracking and speculative tracking.

Systematic tracking involves the systematic gathering of information from signs, until it provides a detailed indication of what the animal was doing and where it was going. In order to reconstruct the animal’s activities, the emphasis is primarily on gathering empirical evidence in the form of tracks and other signs. Systematic tracking involves inductive-deductive reasoning.

Speculative tracking involves the creation of a working hypothesis on the basis of initial interpretation of signs, knowledge of the animal’s behavior and knowledge of the terrain. With a hypothetical reconstruction of the animal’s activities in mind, trackers then look for signs where they expect to find them. The emphasis is primarily on speculation, looking for signs only to confirm or refute their expectations. When their expectations are confirmed, their hypothetical reconstructions are reinforced. When their expectations prove to be incorrect, they must revise their working hypotheses and investigate other alternatives. Speculative tracking involves hypothetico-deductive reasoning.

In systematic tracking, trackers do not go beyond the evidence of signs and they do not conjecture possibilities that they have not experienced before. Systematic tracking essentially involves empirical knowledge based on inductive-deductive reasoning. In speculative tracking the trackers go beyond the evidence of signs. Anticipation and prediction are based on imaginative preconceptions. They conjecture possibilities which are either confirmed or refuted. Speculative tracking involves a continuous process of conjecture and refutation and is a creative science based on hypothetico-deductive reasoning.

Systematic tracking involves a cautious approach. Since the trackers do not go beyond direct evidence, the chances of losing the trail are small. Even anticipation and prediction do not involve great risk of losing the trail, since they are based on repeated experience. Provided the trackers can progress fast enough, they will eventually overtake their quarry. While systematic tracking may be very efficient in relatively easy terrain, it may prove to be very time-consuming in difficult terrain.

Speculative tracking, on the other hand, requires a bold approach. Anticipating the animal’s movements, by looking at the terrain ahead and identifying themselves with the animal on the basis of their knowledge of the animal’s behavior, trackers may follow an imaginary route, saving much time by only looking for signs where they expect to find them. Trackers may visualize animals moving through the landscape and ask themselves what they would do if they were the animals, and where they would have gone. The tracker creates an internal simulation of different possibilities, thereby simulating and predicting the future. By predicting where animals may have been going, the trackers can leave the trail, take a short cut, and look for the tracks further ahead.

In principle, there is a fundamental difference between systematic and speculative tracking. In practice, however, they are complementary, and a tracker may apply both types of tracking. In very easy terrain, such as open, sparsely vegetated, sandy terrain, systematic tracking may be so quick that it may not be worth risk losing the trail by speculation. In very difficult terrain, such as very hard, rocky terrain, a tracker may not get very far with systematic tracking, so that speculative tracking may be the only way to overtake the quarry. Trackers may also alternate between systematic and speculative tracking as the terrain and vegetation changes during the course of tracking an animal.

The Evolution of Tracking and the Origin of Science

Finally, we can now look at when systematic and speculative tracking evolved, and therefore the evolutionary origins of creative science.

A wide array of evidence suggests that hominids were actively hunting, at least by the time that Homo erectus appears about two million years ago (12, 13, 14, 15). The evidence for hunting includes a large proportion of bones with cut-marks indicative of flesh removal from regions of shafts that would not have had flesh had they been scavenged. Evidence for endurance running as early as two million years ago may indicate the evolution of persistence hunting (16, 17, 18, 19). Persistence hunting takes place during the hottest time of the day and involves chasing an animal until it overheats and eventually drops from hyperthermia (17). The earliest evidence of hunting that would have involved systematic tracking therefore goes back about two million years to Homo erectus (5).

The earliest direct evidence of speculative tracking is found about 70 000 years ago. Animals are always alert for predators tracking them, looking back down their own trail. It is therefore not possible to stalk an animal using systematic tracking. Hunting with missile weapons would therefore have required a very advanced level of speculative tracking (5). The bow and arrow and the spear thrower were not invented until quite recently, probably after the origin of modern Homo sapiens (20). The earliest evidence of bow and arrow was found in South Africa and dates to 71 000 years ago (21). Evidence of symbolic activities, including both red ochre and seashells that were clearly collected for their aesthetic appeal, date back to 110 000 years ago in South Africa (22). This may provide indirect evidence of the creative cognitive abilities required for speculative tracking more than 100 000 years ago with the evolution of Homo sapiens (5).

In contrast to systematic tracking, speculative tracking required a fundamentally new way of thinking. The evolution of speculative tracking may have resulted in the cognitive abilities required for creative scientific thinking.

Download pdf of article here

The Origin of Science by Louis Liebenberg is available as a Free eBook at:
http://www.cybertracker.org/science/books

References

1. Wallace, A. R. 1870. “The Limits of Natural Selection as Applied to Man.” In Contributions to the Theory of Natural Selection. A Series of Essays. London and New York: Macmillan.
2. Washburn, S. L. 1978. “The Evolution of Man.” Scientific American, September, vol. 239 no. 3.
3. Pinker, S. 1997. How the Mind Works. London: Penguin Books.
4. Wilson, E. O. 1998. Consilience. The Unity of Knowledge. London: Abacus.
5. Liebenberg, L. 2013. The Origin of Science. Cape Town: CyberTracker.
6. Liebenberg, L. 1990. The Art of Tracking: The Origin of Science. Cape Town: David Philip.
7. Lakatos, I. 1978. The Methodology of Scientific Research Programmes. Philosophical Papers Vol. 1. Edited by J. Worral and G. Currie. Cambridge: Cambridge University Press.
8. Hadamard, J. 1945. The Psychology of Invention in the Mathematical Field. New York: Dover Publications, Inc.
9. Losee, J. 1972. A Historical Introduction to the Philosophy of Science. Oxford: Oxford University Press.
10. Medawar, P. B. 1969. Induction and Intuition in Scientific Thought. Philadelphia: American Philosophical Society.
11. Popper, K. R. 1963. Conjectures and Refutations. London: Routledge and Kegan Paul.
12. Potts, R. 1988. “Environmental Hypotheses of Human Evolution.” Yearbook of Physical Anthropology 41, 93–136.
13. Bunn, H.T. 2001. “Hunting, power scavenging, and butchering by Hadza foragers and by Plio-Pleistocene Homo.” In: Stanford, C.B., Bunn, H.T. (Eds.), Meat-Eating and Human Evolution, Oxford University Press, Oxford, pp. 199-218.
14. Dominguez-Rodrigo, M. 2002. “Hunting and Scavenging by Early Humans: The State of the Debate.” Journal of World Prehistory 16, 1-54.
15. Braun, D.R., J.W.K. Harris, L.C. Bishop, B.G. Richmond, and M. Kibunjia. 2010. “Early hominin diet included diverse terrestrial and aquatic animals 1.95 Myr ago in East Turkana, Kenya,” Proceedings of the National Academy of Sciences (U.S.A.)107(22): 10002-10007.
16. Bramble, D. M., and D. E. Lieberman. 2004. “Endurance running and the evolution of Homo.” Nature 432:345–52.
17. Liebenberg, L. 2006. “Persistence hunting by modern hunter-gatherers”. Current Anthropology. 47, 1017–1025.
18. Liebenberg, L. 2008. “The relevance of persistence hunting to human evolution”. Journal of Human Evolution. 55, 1156-1159.
19. Lieberman, D.E., D.M. Bramble, D.A. Raichlen and J.J. Shea. 2009. “Brains, Brawn, and the Evolution of Human Endurance Running Capabilities.” In F.E. Grine, J.G. Fleagle and R.E. Leakey. (eds.) The First Humans: Origin and Early Evolution of the Genus Homo, Vertebrate Paleobiology and Paleoanthropology, © Springer Science + Business Media B.V. 2009
20. Shea, J.J., 2006. “The origins of lithic projectile point technology: evidence from Africa, the Levant, and Europe.” Journal of Archaeological Science 33, 823–846.
21. Brown, K.S., C.W. Marean, Z. Jacobs, B.J. Schoville, S. Oestmo, E.C. Fisher, J. Bernatchez, P. Karkanas and T. Matthews. 2012. “An early and enduring advanced technology originating 71,000 years ago in South Africa.” Nature. 491, 590-593 doi:10.1038/nature11660.
22. Marean, C.W. 2010. “When the Sea Saved Humanity”. Scientific American, Volume 303, Number 2.

Animal Density and Track Counts: Understanding the Nature of Observations Based on Animal Movements

Derek Keeping and Rick Pelletier

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Abstract

Counting animals to estimate their population sizes is often essential for their management and conservation. Since practitioners frequently rely on indirect observations of animals, it is important to better understand the relationship between such indirect indices and animal abundance. The Formozov-Malyshev-Pereleshin (FMP) formula provides a theoretical foundation for understanding the relationship between animal track counts and the true density of species. Although this analytical method potentially has universal applicability wherever animals are readily detectable by their tracks, it has long been unique to Russia and remains widely underappreciated. In this paper, we provide a test of the FMP formula by isolating the influence of animal travel path tortuosity (i.e., convolutedness) on track counts. We employed simulations using virtual and empirical data, in addition to a field test comparing FMP estimates with independent estimates from line transect distance sampling. We verify that track counts (total intersections between animals and transects) are determined entirely by density and daily movement distances. Hence, the FMP estimator is theoretically robust against potential biases from specific shapes or patterns of animal movement paths if transects are randomly situated with respect to those movements (i.e., the transects do not influence animals’ movements). However, detectability (the detection probability of individual animals) is not determined simply by daily travel distance but also by tortuosity, so ensuring that all intersections with transects are counted regardless of the number of individual animals that made them becomes critical for an accurate density estimate. Additionally, although tortuosity has no bearing on mean track encounter rates, it does affect encounter rate variance and therefore estimate precision. We discuss how these fundamental principles made explicit by the FMP formula have widespread implications for methods of assessing animal abundance that rely on indirect observations.

Read full article here…

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The Value of Animal Tracking Skills

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By Janet Pesaturo

After generations of fading into obsolescence, wildlife tracking has grown in popularity in recent years. No doubt this is due to the work of evolutionary biologist, Louis Liebenberg. He recognized the value of animal tracking skills, and helped traditional African hunter-gatherers use them to earn a living in data collection for wildlife monitoring, research, and anti-poaching efforts.

Part of Liebenberg’s work involved development of the CyberTracker evaluation system, which became an international standard for tracking skills. This elevated the ancient art and science of tracking to a respected discipline within the modern world. But regardless of its status within the modern world, tracking is useful to almost anyone.

Tracking skills deepen your awareness and understanding of wildlife. And that can help you better protect pets, livestock and garden produce; develop competency in hunting; make more informed decisions that impact wildlife; and meet people from vastly different walks of life. Not to mention the fact that it’s great physical and mental exercise, all at once.

Read full article here…

Using Cyber Tracking Technology to Outsmart Poachers

ImageJef Dupain

I’m just recently back in Lomie (on border of the Dja Faunal Reserve in Cameroon) from two days of practical training for rangers on the use of the CyberTracker/Trimble for ecological monitoring and anti-poaching.

Instead of counting living monkeys, elephants, and great apes, we witnessed the arrest of about 15 poachers on more than five different occasions. We have been hiding and running, sleeping on the ground next to the fire with guards at both sides of our overnight spot— switching every two hours, assuring security. The Conservator, Achile Mengamenya, who was with us, has a good and dedicated team of park wardens (we were about 20). Nobody complains, while equipment is lacking, and everybody works hard. We were fed water and some rice and tomato sauce in the evening, and in the morning we have one or two beignets for each.

The total amount of confiscated illegal wildlife, from the poachers, is surprising—sitatunga, forest duikers, living and dead pangolin, several species of monkey, freshly killed or smoked. No chimp, gorilla or elephant meat though…as these species are victim of a different type and more specialized category of hunters.

We heard only one group of chimps was heard about 1 km from our campsite, so we can consider that this periphery of this Natural World Heritage site is probably almost hunted out.

However, based on the interrogations of the arrested poachers, and witnesses of some park guards, it is clear that the Dja is still housing good numbers of all species, and remains attractive for a lot of people who prefer to put snares in the park instead of working on their fields in the village. With the Dja managers lacking any support for the last few years, and no control happening anymore, the Dja Biosphere is being hit very hard. And poachers are getting increasingly aggressive. Over the last few weeks, one guard got shot in his arm, another received a blow of a machete above his eye, and last night inhabitants of Lomie attacked the post of the Conservator and his team.

Alain Lushimba (who is here with me, taking the lead in the training on cybertracker) and myself agree on the area’s high resemblance with the Lomako Yokokala Faunal Reserve. While being a beautiful forest with high potentials for biodiversity, the Dja is probably in the same conditions today as the Lomako forest was in 2004 when AWF started working in DRC. Support is needed. “Performance Based Management” and “Evidence-based Conservation” à la Lomako, and the lessons learned, will prove most helpful here. The park authorities and their team are extremely happy with the support we are giving.

Today, we will adapt a work plan in order to respond, first of all, to the absolute priority to get those poachers out of the Reserve, restore law and order, and let the people know that the conservator and his team are operational again.

All paths will be georeferenced, poaching camps destroyed, traces of gorillas, chimps, elephants, bongo and buffaloes recorded, and groups of monkeys—now all frightened—counted. Data will be shared with AWF headquarters the AWF-GIS (mapping) Centre. Evaluation on the ground is planned about 4 to 5months from now.

About the Author

Jef Dupain is AWF’s Director, African Apes Initiative. He holds degrees in biology and zoology from the University of Antwerp, has served as an associate professor for great ape conservation at Kyoto University, and has nearly 20 years of practical experience working on great ape conservation in and out of the field—he has an esteemed reputation as an authority on great ape conservation in Africa.

Using technology in the fight against rhino poaching

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Information from Optron

Controlling rhino poaching with the country’s eyes on you is just one of the many tasks that fall under managing the massive area that is the Kruger National Park (KNP). With nearly 2-million hectares of diverse flora and fauna to keep track of, and only about 300 field rangers to do so, monitoring the park is a logistical nightmare. However, the use of innovative technology and customised open-source software is making the ongoing conservation of South Africa’s natural heritage possible. The Kruger National Park is divided into 22 sections, each managed by one section ranger with a number of field rangers to patrol each section every day. Field rangers are imperative for conservation – from the ground, they contribute directly to the management of the park by collecting basic environmental data during their daily patrols. Information such as the distribution of rare and endangered species, availability of surface water and disease outbreaks are integral in the ongoing management of the park. These indicators are used by the SANParks management to provide an early warning system for disease outbreaks, identify trends in illegal exit and entry points, and enable the detection and control of invasive alien species. Therefore, it is extremely important that the data collected is accurate, but when information is recorded manually it is almost impossible to ensure its complete accuracy, which makes collating and using the raw data for decision-making difficult.

When faced with the unique set of challenges that the Kruger National Park presents in terms of ecological conservation, Douw Swanepoel, a Section Ranger of the Kruger National Park, recognised the value of the CyberTracker system in 2000 and soon afterwards 44 GPS devices were purchased for the park. CyberTracker is an open-sourced programme developed by Louis Liebenberg who felt that there was a need for a tracking programme that could work from a palmtop device. The programme is freely available, and the Kruger National Park team has customised the programme specifically for the park’s needs with databases including ranger patrols, vegetation condition assessments, animal behaviour monitoring and invasive species distribution mapping.

The CyberTracker programme used on the Trimble device form a solid partnership, producing a piece of equipment designed specifically to assist with conservation in the park. With an icon-based interface and descriptions in both English and local language, the CyberTracker system is easily accessible to field rangers regardless of literacy. Information is recorded with latitude and longitude coordinates through the integrated GPS system, ensuring that separate GPS skills are not necessary, and as data is captured electronically using graphic check lists, inaccuracy is reduced and minimal training is needed before the rangers can begin recording data. Moving map functionality allows the ranger to pinpoint his exact location on a 1:50 000 or 1:250 000 topographical map or aerial photograph should a ranger urgently need assistance from the SANParks office. With a built-in camera, rangers can document and geotag exactly what they see and send the photo immediately from the field to the office for review, increasing field to office collaboration.

“The device assists the field ranger to accurately call for assistance once a suspicious spoor or even a poached rhino is found,” says Louis Lemmer, from the SAN Parks Honorary Rangers’ National Executive Committee when asked how the device is helping in the fight against rhino poaching. “Previously they had to rely on their general knowledge and geographical features when calling for help, often leading to slow response times due to possible inaccuracies and confusion. The use of GPS technology removes this. Furthermore it is now possible to track and accurately map poacher movements. In this way patterns can be established and plotted on maps. This helps to plan preventative operations.”

The devices are useful as part of a long-term solution because at the end of each day, the data that the field ranger has collected is downloaded on to the section ranger’s computer and then uploaded to SANParks’ GIS/RS Analyst, Sandra Mac Fayden. This allows her to create a full, sophisticated picture of the environmental state of the Kruger National Park with intricate detailing that can only be sourced by professional field rangers with a working knowledge of the area. Once the data has been downloaded it is archived and documented so that it is usable in the long-term.

Thresholds in the programme are set so that the limits of acceptable change in the environment can be monitored. The data in the database is then used in routine analyses run through the programme in order to assess whether there is any danger of ecological factors exceeding those thresholds, thereby warning park management of any unacceptable changes. For example, monitoring data is analysed for each river which flows through the Kruger National Park and should water levels lower and exceed the threshold set by park management, urgent action is required.

With something as volatile and ever-changing as ecology, correct data is essential in its efficient management. In the fight against rhino poaching in the Kruger National Park where intervention and constant vigilance is necessary, rapid decision making is critical and this is only possible when every step of the data collection and analysis is accurate. By using the irreplaceable knowledge and ability of field rangers, curbing human error through easy-to-use software and technology with GPS capabilities, the SANParks team is efficiently managing the vast and diverse ecosystem of the Kruger National Park and engaging in the ongoing fight against rhino poaching.

Read full article here…

Timbavati now home to one of only four Master Trackers in South Africa

ImageNews24 2014-01-30

South Africa – Have you ever thought about the skill it takes (not to mention the guts) to be able to track animals of the wild? We’re talking lions, leopards and pretty much every other animal you can think of.

Lucas Mathonsi from Sgagula, South Africa knows what we’re taking about because he is now one of only four coveted Master Trackers in the world.

Where the story begins:

His story begins as a five-year-old boy who used to accompany his father who was a ranger in the Timbavati reserve. It is here that Lucas Mathonsi was taught about the animals in the reserve and how to track them.

Over the next 47 years, Lucas honed his skills working as a tracker in the Timbavati and Balule reserves, before joining Lion Sands in 2006 as a Senior Tracker. Lucas is renowned for his particular penchant for tracking the elusive Leopard.

The story now:

In 2013, under the tutelage and mentorships of Louis Liebenberg, Juan Pinto and Wilson Masia, Lucas achieved the much coveted Master Tracker qualification, becoming one of four existing Master Trackers in the world, and only the second tracker to be awarded this prestigious qualification in the Lowveld since 1994.

What it takes to be a qualified tracker:

The Cybertracker qualification is an assessment that was created by Louis Liebenberg after realising that the art of tracking is a skill and talent that needs to be recognised and validated. An assessment system has been created and revolves around the identification of tracks as well as following animal tracks and trails in order to find the animal. For detailed info, click here.

With hard work comes great reward:

In celebration of this remarkable life achievement, the Lion Sands Game Reserve will be naming the link road between Lion Sands Sabi Sand and Lion Sands Kruger National Park the “The Mathonsi Link”.

BACKWARD COMPATIBLE

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CyberTracker fuses ancient knowledge with cutting-edge technology

By Nancy Bazilchuk

July 2008, Conservation Magazine

In 2003, trained trackers combing the rich jungles in the Republic of Congo’s Lossi Sanctuary for gorillas and chimpanzees stumbled upon a disturbing trend. Duikers, dog-sized antelopes that weave and dive through the jungle’s dense undergrowth, were dying at an astounding rate—local indices dropped 50 percent compared to a 2000 census. Gorillas and chimpanzees were dying at similar rates. Blood tests confirmed the culprit was the deadly virus Ebola. The surprise was that no one had previously known that Ebola killed antelopes.

Yet there was no doubt the terrible data were real. The findings were based on hundreds of observations precisely mapped with CyberTracker software. CyberTracker allows hand-held computers to use stylized images instead of text for data entry. Its heart is a menu of icons that depict whatever elements researchers choose. Trackers need only select a pre-programmed image that matches what they see—a grazing antelope, a carabid beetle—and with one tap, the observation is recorded and paired with geographic coordinates via a Global Positioning System (GPS) link. Trackers hardly have to break stride as they work, which allows enormous numbers of data points to be amassed with little effort. The information can be downloaded to a computer and immediately mapped, thus enabling scientists to make real-time observations about trends, such as the ones from Lossi Sanctuary that showed duiker declines.

The program’s greatest strength, and the feature that sets it apart from its competitors, is its ability to transcend language and culture because of its reliance on images, not words, for data entry.

CyberTracker creator Louis Liebenberg, a South African scientist and author, first came up with the idea in 1996 while tracking with a group of Kalahari Bushmen. Liebenberg realized that he could help save the Bushmen’s rapidly disappearing knowledge if he could find a way to help trackers, who could neither read nor write, record their observations. Thus CyberTracker was born.

CyberTracker’s biggest impact has been in South Africa’s national park system. Kruger National Park official Judith Kruger says that rangers use 110 hand-held computers daily to record sightings on patrol—everything from broken fences to elephant-damaged trees to invertebrates. Liebenberg and two rangers from South Africa’s Karoo National Park used it to document seasonal shifts in black rhino feeding behavior. And CyberTracker is being used to record garbage found littering beaches in Gabon as a way to persuade source nations to help clean up. The program allows for remarkable precision: one 500-m-long section of shoreline in Loango National Park was covered with 535 plastic water bottles and 560 flip-flops among more than 3,000 bits of trash.

The software is free and has been downloaded by more than 6,000 people since it was first made available on the Internet in 2000. About 500 users from 30 countries have registered the software—from the entire Spanish National Park Service to a multinational research group in the Arctic to individual trackers in the U.S. With the help of a 2-million-Euro (approximately US$2 million) grant from the European Commission and Conservation International, Liebenberg is developing the next generation of Cyber-Tracker. Three versions will offer increasingly complex programming features along with conservation-specific analysis tools to allow the calculation of standard measures such as Patrol Effort or Index of Abundance.

Liebenberg says the biggest benefit has been to give an authoritative, scientific “voice” to skilled trackers in Africa who can’t otherwise share their knowledge because they can’t write. Karel Benadie is a ranger and expert rhino tracker who worked with Lieben-berg in Karoo National Park. He told Liebenberg that his inability to write down his rhino observations meant “the PhDs would never listen to him before,” Liebenberg said. With Cyber-Tracker, “Now they do.”

More on the Tracker: www.cybertracker.co.za

Liebenberg, L. et al. 1999. Rhino tracking with the CyberTracker field computer. Pachyderm 27:59-61.

Leroy, E. et al. 2004. Multiple Ebola virus transmission events and rapid decline of Central African wildlife. Science 303:387-390.

About the Author
Nancy Bazilchuk is a freelance writer based in Trondheim, Norway.

Yes, You Were Born to Run

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BY RICHARD CONNIFF, APRIL 16, 2008, Men’s Health

Millions of years of genetic mutation and adaptation have produced a singular animal whose body, mind, and spirit are primed to sprint as if life depended on it. That animal is you. So why are you just standing there?

During his first full-throttle “persistence hunt,” the South African biologist Louis Liebenberg was working with bushmen in the Kalahari Desert in the early 1990s. Armed with handmade bows and arrows, the hunters had been stalking kudu — a nimble antelope, slightly smaller than an elk. When a young stag split off from the herd, the bushmen ran flat-out after it.

The kudu moved quickly out of sight in the brushy Kalahari landscape. But keeping up was more than just a matter of running; the hunters also needed to pick up footprints in the sand on the fly. Liebenberg, then age 30, hadn’t done the conditioning to be a long-distance runner, and he was wearing heavy leather boots as a precaution against poisonous snakes. And this was shaping up to be a hard run.

In persistence hunting, the trick is to trot almost nonstop in the heat of the midday sun, pushing the animal along so that it never has time to recover in the shade of an acacia tree. The Kalahari hunters have figured out how to play one critical advantage in a deadly game that pitches their survival against that of animals: Humans have an evaporative cooling system, in the form of sweat; antelope don’t. When conditions are right, a man can run even the fastest antelope on earth to death by overheating.

But after 10 or 12 miles, Liebenberg was overheating, too, and by the time he reached the kill, he was so dehydrated he’d stopped sweating. The only liquid in sight was the stomach water of the dead animal, but his companions stopped him from drinking it, because kudu eat a leaf that’s toxic to humans. If one of the hunters hadn’t run back to camp for water, Liebenberg figures he would have died. He also figures the experience taught him the answer to an ancient question.

What makes people run?

Why do 11 percent of Americans and tens of millions of people around the world tie on running shoes and clock their weekly miles? The three most recent presidents of the United States have put in time as runners (and earlier this year, one candidate, Mike Huckabee, trained for the Boston Marathon while campaigning for the U.S. presidency). The president of France, Nicolas Sarkozy, is a runner. And beyond the vast army of ordinary joggers, it can sometimes seem as if the entire planet is trembling beneath the footfalls of ultramarathoners, Ironmen, and other endurance athletes.

Runners also make the news by dying while running–two died in the 2006 Los Angeles Marathon, another during unseasonably hot weather at October 2007’s Chicago Marathon, and yet another a month later, when 28-year-old Ryan Shay died of heart failure during the Olympic Marathon trials. So the question is asked not just in puzzlement but sometimes in anger and sorrow: What makes us run?

The answer, according to a controversial body of research, is that our passion for running is natural. A small group of biologists, doctors, and anthropologists say our bodies look and function as they do because our survival once depended on endurance running, whether for long-distance hunts like the one Liebenberg witnessed or for racing the competition across the African savanna to scavenge a kill. The prominent science journal Nature put the idea on its cover, with the headline “Born to Run.” And in his book Why We Run, the biologist and runner Bernd Heinrich, Ph.D., argues that something exists in all of us that still needs to be out chasing antelopes, or at least dreaming of antelopes. Without that instinct, “we become what a lapdog is to a wolf. And we are inherently more like wolves than lapdogs, because the communal chase is part of our biological makeup.”

Daniel Lieberman, Ph.D., first started to think about whether humans evolved for running as he was running a pig on a treadmill. A colleague, the University of Utah biologist Dennis Bramble, happened to look in. “That pig can’t keep its head still,” he remarked.

This was an observation Lieberman admits he never made in months of running pigs. Bramble invited him next door, where a dog running on a treadmill was holding its head “like a missile.” The conversation turned to the nuchal ligament, a sort of shock cord stretching from the back of the skull down the neck. It keeps the head from pitching back and forth during a run. Dogs have one because they’ve evolved for running. Pigs don’t.

Lieberman and Bramble were soon digging through bone collections. The skulls of chimpanzees, our closest primate relatives, showed no evidence of a nuchal ligament. But skulls of the genus Homo, which includes modern humans, did. “We had one of those epiphany moments that happen occasionally in science,” says Lieberman. Much as chimps were built for life in the treetops, the two scientists began to ask if humans were built for life on the run.

Almost 20 years later, I’m the pig on Lieberman’s treadmill. A postdoctoral fellow, Katherine Whitcome, has me trussed around my hips, chest, neck, and forehead with gyroscopes and accelerometers for measuring angles and speed of movement. The insoles of my running shoes have been fitted with inserts laced with devices that will measure my heel strikes and the way I roll off my fifth metatarsal. Wires run through a duct-tape collar to an assortment of electronic boxes on a nearby shelf and from there to Whitcome’s computer.

Lieberman starts the treadmill. “Pretend that the piece of yellow paper on the wall is your antelope,” he says. The speed kicks up to 6.7 miles per hour, and as my stride lengthens to keep pace, a dismal, office-worker thought passes through my mind: I salivate for Post-it pads.

I have never been a hunter. But as a journalist, I have been in on chases after real animals and close enough to witness a kill. Once I was following a fox hunt on foot through hilly country in Ireland’s County Meath. The riders came thumping down a muddy lane, shaking the earth with the staccato of metal horseshoes clattering on the occasional rock. They paused as the hounds searched a stand of woods. Flocks of blackbirds fled in alarm from the bare treetops. Then a hound let out the first strangled cry as he caught a hot scent, and a moment later a fox made a beeline out of the woods and up a hill. After a moment of confusion, the hounds also burst into the open. The horses took off. I followed, leaping from hummock to hummock to traverse a wet section and then sprinting up a slope, feeling as fleet and sure-footed as the 9-year-old who was running beside me. On another hunt, I saw the hounds chase a fox into a wetland, cascades of water kicking up around their feet. Then the distance closed and the fox vanished in a bloody cloudburst.

I suppose I should have felt remorse. But what I honestly felt was exhilaration at the close connection to the hunt, with life and death in the balance. The sudden power of forgotten urges astonished me. Had they been my kills, I would have smeared my face ritualistically with the blood.

Anyone who has put in some miles knows how good running can feel, once it stops feeling bad. But beyond the way it feels, medical evidence also suggests that humans are built for endurance exercise. In response to a good training program, for instance, the left ventricular chamber of the heart can increase as much as 20 percent in volume. The chamber walls thicken, too. So the heart fills up faster and pumps more blood to the rest of the body. The coronary arteries also change, dilating more rapidly to meet the body’s demand for oxygen. Endurance exercise won’t make anyone live forever. But it seems to make the cardiovascular system function the way the owner’s manual intended.

In the skeletal muscles, increased blood pressure causes new capillaries to emerge. The mitochondrial engines of the cells ramp up to consume energy more efficiently, helped along by an increase in the production of various antioxidants. These changes in the heart and extremities together typically boost the maximum amount of oxygen the body can consume each minute by 10 to 20 percent. For men who used to become short of breath slouching to the fridge for a beer, VO2 max can increase even more. Lapdogs start to function like wolves.

More surprisingly, the brain responds as if it was built for endurance exercise, too. Everybody knows about the runner’s high, that feeling of euphoria thought to be triggered by a rush of endorphins to the reward centers of the brain, usually near the end of a good, long workout. (Running for dinner, as part of a hunt, could very well amplify that effect; in essence, a love of running could lead to more ample dining opportunities.) But researchers have discovered lately that exercise affects the function of 33 different genes in the hippocampus, which plays a key role in mood, memory, and learning. By stimulating growth factors, exercise also produces new brain cells, new and enhanced connections between existing cells, new blood vessels for energy supply, and increased production of enzymes for putting glucose and other nutrients to work.

People who exercise regularly perform better on some cognitive tests: Run more, think better, hunt smarter, eat better. Exercise also seems to buffer the brain against neurological damage, reducing the effects of stress and delaying the onset of Alzheimer’s and other diseases. Most significant, exercise helps prevent and alleviate depression, which afflicts one in six Americans and costs $83 billion a year. In fact, studies suggest that exercise works as well as pharmaceutical antidepressants, and that the effect is “dose dependent”–that is, the more you exercise, the better you feel.

Running may also be the forgotten reason for many of the movements — the turn of a shoulder, the sway of a hip — we think of as most gracefully human. The lines of a Theodore Roethke poem come to mind: “My eyes, they dazzled at her flowing knees; / Her several parts could keep a pure repose, / Or one hip quiver with a mobile nose / (She moved in circles, and those circles moved).”

To put it in the less romantic language of anatomy, it’s the reason we are sweaty, hairless, elongated, and upright. It’s also the reason, Lieberman and Bramble say, for the exaggerated size of the human gluteus maximus. Their studies show that our big buttocks don’t matter much in walking on level ground, but they are essential for staying upright when we run.

Our legs have evolved for running, too, says Lieberman, and not merely in length. “Human legs are filled with tendons.

Chimpanzees have only a few, very short tendons. Tendons are springs. They store up elastic energy, and you don’t use elastic energy when you walk — at least not much of it.” But when you run, storing up the force of impact and releasing it as you kick off is essential. Smart runners know they can release that force more efficiently by using a springier gait, says Lieberman. “It’s really about the jump.”

Other scientists have begun to incorporate the “endurance-running hypothesis” into their research. Timothy Noakes, M.D., a South African physician whose book The Lore of Running is the bible of technical running, argues that misunderstanding human evolution can pose a deadly hazard to endurance athletes. British and American runners in particular have fallen prey to the notion that it’s essential to stay heavily hydrated during a race. Runners have died of hyponatremia brought on by drinking too much liquid while sweating profusely, which diluted their blood sodium to a lethal level.

“Humans evolved not to drink much at all during exercise,” says Dr. Noakes, chairman of exercise and sports science at the University of Cape Town. “If they had to stop every 5 minutes to drink, they would never have caught the antelope.” The secret for modern runners, he says, is to drink just enough to minimize thirst. “The best runners in any culture are the ones who run the farthest and drink the least, and the bushmen are the classic example. Humans are built to become dehydrated. That’s the point.”

But other researchers have attacked the endurance-running hypothesis, mainly on cultural grounds. Writing last year in the Journal of Human Evolution, Travis Pickering and Henry Bunn, anthropologists at the University of Wisconsin, argued that persistence hunting was too rare to have played a large role in our evolution. Bunn also calls endurance-running proponents “incredibly naive” in failing to consider alternate explanations of how early humans secured meat. They may have banded together as “power scavengers,” for instance, to steal kills from ambush predators. In any case, he says, meat was a relatively minor, though coveted, part of their diet.

Lieberman all but rolls his eyes at their arguments. Early humans didn’t have fire to cook meat and release its nutrients until 250,000 years ago. They didn’t have the bow and arrow until 20,000 years ago. “But we know that people have been hunting for 2 million years. The best weapon they had available to them was a sharpened wooden stick. I’m not exaggerating. How the hell are you going to kill an animal with a sharp wooden stick? It’s incredibly dangerous. You have to move close to the animal, which means the animal can kick you or gore you.”

And the alternative? Simply run the animal for 5 or 10 miles until it’s dying of heatstroke, and then knock it over with a feather. “That’s it. It’s amazing. It’s so easy.”

So if humans evolved for distance running, does that mean we should all be out notching up marathons now? Even ardent runners generally don’t think so.

On a winter afternoon, Walter DeNino, a medical student at the University of Vermont, is doing his regular training run along the Lake Champlain shoreline. Back in high school, he says, he logged so many miles that he ended up on crutches at the age of 15, with multiple stress fractures. He started to think that maybe some people really aren’t built for long-distance running after all, or at least not for the distances we’re tempted to run by the addictive nature of the sport.

Eventually, DeNino took up the triathlon, with a training emphasis on swimming and cycling. He also founded a coaching and sports-nutrition company, Trismarter.com, which aims, among other things, to lure lapdogs and couch potatoes back to the active life. The triathlon is a much newer sport than the marathon, he says, and it’s more welcoming to different body types.

That seems to be how nature works, too. Heinrich points out that humans have hunted with weapons long enough for natural selection to favor survival talents other than running. The rise of agriculture also may have changed the shape of the human animal. So some people have the light, lean, almost birdlike build of the ideal long-distance runner, and others are built squat and strong, for moving earth. According to one line of research, the cultures of our ancestors may even give some people a genetic predisposition to or away from long-distance running.

And yet as I ran on the treadmill that day in Lieberman’s Harvard laboratory, it seemed to me that the proponents of endurance running were onto something persuasive and appealing about human nature. There were moments when I forgot about the Post-it-pad antelope. Instead, I imagined a real antelope racing out ahead of me. I imagined my distant ancestors on the African savanna, hunting not quite beside me, but somewhere within. And just the thought of that connection lifted me out of this mundane world and away to someplace wild and even a little sacred.

Later, Heinrich told me about feeling that same connection when he was doing research in Zimbabwe’s Matobo National Park. As he looked under a rock overhang, he suddenly found himself staring at a wall drawing made thousands of years ago by bushman hunters. It showed a series of stick figures, bows and arrows in hand, arms pumping, legs extended at full stride in the heat of the chase. Big, horned wildebeests loomed in the background. And off to the right, one hunter was raising both arms in an unmistakable gesture of triumph. It was the same gesture Heinrich had instinctively made the first time he won a marathon, the same one countless other runners still make as they cross the finish line. “Looking at that African rock painting,” Heinrich later wrote, “made me feel that I was witness to a kindred spirit, a man who had long ago vanished yet whom I understood as if we’d just talked.”

And, he concluded, “There is nothing quite so gentle, deep, and irrational as our running — and nothing quite so savage and so wild.”