The Relevance of Persistence Hunting to Human Evolution

1. What they did

Some researchers think that running down prey over long distances, called persistence hunting, helped shape the human body as a long-distance runner, starting about two million years ago. In 2007, Pickering and Bunn argued that persistence hunting was extremely uncommon and probably did little to drive that evolution. They pointed to Louis Liebenberg’s own observations, saying only two hunts in 20 years had been spontaneous.

In this short reply, Liebenberg puts his observations in context and argues that persistence hunting may once have been common. He:

• Explains his fieldwork. Working without funding, he could not visit the Kalahari for long stretches. To study the hunters’ tracking skills away from social problems such as alcoholism, he camped with two to four hunters at a remote pan. Only 46 “hunting days” (in 1985, 1990, 1991 and 1992), with five hunters from Lone Tree in Botswana, offered a chance to see a spontaneous persistence hunt.
• Compares their success with other records. He scales the kills from those 46 days to a year, using Lee’s (1979) finding that hunter-gatherers work about two to three days a week.
• Looks at the ethnographic, historical and ecological context, from earlier anthropologists’ records and studies of past climate.
• Proposes an evolutionary hypothesis linking levels of tracking skill to the evolution of persistence hunting and human thinking.

2. What they found

Hunting success

• In the 46 hunting days, the hunters killed three large animals: two kudus by persistence hunting and one wildebeest with a bow and arrow.
• That works out to about 6.8 to 10.4 large antelope a year, or about 2.3 to 3.5 per hunter a year. This matches Lee’s (1979) long-run estimate of two or three large antelope per hunter per year, so the hunters were not “uncommonly good”.
• In the right conditions, persistence hunting had a much higher success rate than bow-and-arrow hunting. The bow and arrow gives many more chances, but succeeds far less often per attempt.

Why persistence hunting may look rare

• It needs no special weapon, so anthropologists may not have known to ask about it, and hunters may not have mentioned it. One hunter said that other researchers stayed in the village and only wrote down what hunters told them.
• Few anthropologists went out with hunters, let alone ran with them in heat of up to 42 °C. One hunter at first told the author he could not run with them because “white men cannot do this”.
• Silberbauer (1981) wrote that persistence hunting rarely succeeded unless the animal was weakened. But all the animals the author saw run down were healthy. He admits that he himself first doubted the hunters’ accounts in 1985, until he saw a hunt in 1990.

A changing way of life

• Fencing from the 1950s devastated Kalahari wildlife. Pastoralists and their herds moved in after a long drought in the late 1960s, and hunting has become less important since the 1960s. In 1992, a hunter said wildlife was scarcer and they were struggling to hunt.
• Dogs, and later horses, spread through the Kalahari and are more efficient than bow-and-arrow or persistence hunting. In 1985, hunters at Ngwatle Pan used only dogs and snares.

Past habitats

• During long droughts, such as 140,000 to 70,000 years ago, deserts expanded, so the arid conditions of the southern Kalahari may once have covered much of southern Africa and possibly parts of central Africa.
• Major steps in human evolution, including the origin of the genus Homo, coincide with shifts to drier, more open country.
• Tracking gets harder moving north from the sparse southern dunes to the thicker vegetation and woodland of the central and northern Kalahari.

3. What they concluded

• The scarcity of written records of persistence hunting does not mean it was rare. It may simply be that anthropologists able to observe it were rare.
• The recent hunts may be “the tail-end of a dying tradition”. Persistence hunting may have been more common before the bow and arrow, and before hunting with dogs and horses.
• A simple form may first have developed in easy tracking terrain during droughts. Early Homo may have targeted young or weakened animals and, if pressed to survive, made up for lesser tracking skill by trying more often, losing tracks more often but still succeeding often enough.
• The sophisticated form practised by modern hunters in difficult terrain may be a very recent development, and may have contributed to the evolution of modern human intellect.
• Without a better hypothesis, persistence hunting and scavenging remain plausible explanations for the evolution of endurance running.

4. How tracking was or was not used

Tracking is central to the argument. Persistence hunters follow an animal’s trail until it is exhausted, and the author draws on his earlier observations of !Xõ and /Gwi hunters doing this. He describes three levels of tracking (Liebenberg 1990):

• Simple tracking: following clear footprints in ideal conditions.
• Systematic tracking: a more refined form, recognising signs where footprints are not obvious or easy to follow. Both use inductive-deductive reasoning; the difference is the degree of skill.
• Speculative tracking: needed on harder ground and in thicker cover. The tracker interprets signs, forms a hypothesis about what the animal was doing, and uses it to predict where the animal is going. This hypothetico-deductive reasoning is a fundamentally new way of thinking, also used in scientific research.

Modern trackers combine systematic and speculative tracking depending on the terrain.

5. Tracker or observer certification

Reported but not validated. The author refers to the hunters’ “exceptional tracking skills”, but no certification or test of their skill is described in this paper.