Please note: This is a discussion about how ancient humans hunted and killed animals. If you find these ideas disturbing, it is probably a good idea to skip this post.
Last week I exchanged several comments with my friend Sean at Prague Stepchild about his post The Myth of Persistence Hunting. Persistence hunting is a strategy where an animal is chased (hunted) until it collapses from heat exhaustion. Let’s just say that there is a good bit of debate about the relative importance of persistence hunting as a survival strategy for our earliest human ancestors (2.5 million years ago until the invention of stone weapons).
My interest in this topic came from one chapter in the book Born to Run by Christopher McDougall. McDougall’s belief is that humans evolved to run long distances and by exploiting this unique advantage were able to practice persistence hunting as a primary means of gathering sustenance. What I would like to explore is whether or not the idea of running as an evolutionary advantage implies long distance running (vs. short duration sprinting).
If you are inclined to watch, here is a video produced by the BBC showing a modern-day persistence hunt as practiced by a group of San of the Kalahari Desert.
Most of the thoughts in this post are speculative on my part; however I will try to provide a few references to support my thinking. You may also want to check out these posts by John Durant and Mark Sisson for their take on the topic.
Human Adaptations for Running
As I mentioned in this previous post, there is good scientific evidence for a number of specific adaptations that have occurred in humans that suggest an advantage in being able to run efficiently.
Listed below are a sub-set of the adaptations as outlined in the paper Endurance Running and the Evolution of Homo by Daniel Lieberman and Dennis Bramble:
- “Collagen-rich tendons and ligaments in the leg store elastic … energy”
- “During running, the elastic structures of the plantar arch function as a spring, returning approximately 17% of the energy generated….”
- “Another possible structural modification relevant to running is the nuchal ligament.” (helps keep your head stable)
- “Humans possess many derived features related to heat dissipation, including … sweat glands for evapo-transpiration and reduced body hair.”
In total the paper cites approximately 25 changes that make a compelling case that humans evolved to be runners. My issue with this theory isn’t with the logic around these adaptations, but rather the conclusion that the adaptations yielded an advantage specifically to endurance running as opposed to running in general.
Persistence hunting as presented in Born to Run suggests a model that looks similar to the video of the San above; however given that this mode of hunting is all but extinct in humans, I would argue that other strategies might have been more efficient and required less of an endurance mode of running. (Let the speculation commence.)
1) Using larger hunting parties that employ a better division of labor – by spreading out the hunting group and taking advantage of an individual animal’s desire to rejoin a herd, the running might look more like a series of sprints with lots of rest periods.
2) Targeting injured animals within the herd – this is certainly a strategy employed by other predators.
3) Targeting younger animals – these would require much less of a chase over a shorter distance.
4) Taking advantage of maternal instincts – female animals would be less likely to abandon their offspring and it would make them much easier to identify if they attempted to reintegrate with the herd.
5) Scavenging – hunters could take advantage of bursts of speed to retrieve prehistoric “road kill” and quickly retreat to safety.
Another observation I would make is that humans are exceptional at mimicking good ideas. If it makes our lives easier/better, we find no shame in copying. Whether it is Bottlenose dolphins working in teams to drive prey into shallow waters, wolves chasing caribou off of a cliff (Mech), or chimpanzees cooperating to kill colobus monkeys (web article), using intelligence to augment ability is a powerful combination. While I obviously can’t prove it, I am pretty sure that our ancestors learned a lot about tactics from other predators.
In looking at the above, I would say that running would have certainly been an advantage to most of the modified versions of persistence hunting; however I think the evidence is just as compelling that the running was sprinting as opposed to endurance running.
Other thoughts/comments/opinions and theories are welcome.