"only when chased"

Humans hot, sweaty, natural-born runners

Hairless, clawless, and largely weaponless, ancient humans used the unlikely combination of sweatiness and relentlessness to gain the upper hand over their faster, stronger, generally more dangerous animal prey, Harvard Anthropology Professor Daniel Lieberman said.

The evidence belies the long and firmly held belief that humans are the animal world's biggest wimps and, if not for our big brains and advanced weapons, we'd be forced to subsist on fruits and vegetables, always in danger of being gobbled up by fiercer predators.

The problem with that theory, Lieberman said, is that we began adding meat to our diets around 2.6 million years ago, long before we developed advanced weapons like the bow and arrow, which was developed as recently as 50,000 years ago.

While some of our ancestors' meat-eating may have been due to scavenging, Lieberman said the appearance about 2 million years ago of physical adaptations that have no impact on walking but that make humans better endurance runners provide evidence that early scavengers became running hunters.

Specifically, we developed long, springy tendons in our legs and feet that function like large elastics, storing energy and releasing it with each running stride, reducing the amount of energy it takes to take another step. There are also several adaptations to help keep our bodies stable as we run, such as the way we counterbalance each step with an arm swing, our large butt muscles that hold our upper bodies upright, and an elastic ligament in our neck to help keep our head steady.

Humans, he said, have several adaptations that help us dump the enormous amounts of heat generated by running. These adaptations include our hairlessness, our ability to sweat, and the fact that we breathe through our mouths when we run, which not only allows us to take bigger breaths, but also helps dump heat.

"We can run in conditions that no other animal can run in," Lieberman said.

While animals get rid of excess heat by panting, they can't pant when they gallop, Lieberman said. That means that to run a prey animal into the ground, ancient humans didn't have to run further than the animal could trot and didn't have to run faster than the animal could gallop. All they had to do is to run faster, for longer periods of time, than the slowest speed at which the animal started to gallop. Most animals would develop hyperthermia -- heat stroke in humans -- after about 10 to 15 kilometers, he said.


41 Responses:

  1. skreidle says:

    That's quite interesting! :)

  2. Ok, and what did we KILL animals with once we caught up to them with our springy tendons? Our ferocious teeth and claws?

    Til we had tools, humans were scavangers that stuck to insects, grubs, and rodents.

    • Ok, reading more carefully now, he's claiming we ran them into death by hyperthermia. Ok, then what? We ate them raw through the skin?

      • rapier1 says:

        Stone tools have been used for quite some time. Several million years. Pick up a rock, bring it down on a head, time to eat. The thing that didn't come about until relatively recently was complex weapons like bows and arrows - hunbting from a distance weapons.

        • Ah, that makes more sense. I thought the anthropologist in question was not including such tools. I missed the *distance* weaponry part of the claim.

      • drkscrtlv says:


        We eatss it raw through itss sskin.

      • elanswer says:

        *giggle* Hyperthermia=cooked meats yummy!!!!

  3. astatine210 says:

    "Humans are terrible athletes in terms of power and speed, but we're phenomenal at slow and steady. We're the tortoises of the animal kingdom," Lieberman said.

    Hang on, aren't the tortoises of the animal kingdom... the tortoises?

    • chuck_lw says:

      >Hang on, aren't the tortoises of the animal kingdom... the tortoises?

      Maybe the tortoise was our only natural predator for a couple million years.:-)

      Og nearly collapsed. After about 70 kilometers, he couldn't run another step, but he had to. If he stopped for rest, he knew sleep would take him. And sleep meant death. He looked back across the grasslands he'd fled through. Somewhere back there -- traveling slower than him, but with much more endurance -- a patient, persistent predator marched onward, following Og's scent.

      Og knew.

      The tortoises were coming.

  4. I wouldn't say "no other animal", as kangaroos basically play the same strategy, but take it much further.

    • drreagan says:

      Apart from the hunting part.

      • etfb says:

        So speaks a man who's never been savaged nearly to death at the claws and razor-sharp teeth of a huge, vicious, carnivorous Skippy. "Ha!" I say to you from my wheelchair, somewhere in the Australian Marsupial Witness Protection Programme. Speak not of topics you do not understand, ye knowlessman!

  5. This idea was amusingly reported in a 1996 episode of This American Life!


    To sum up: They tried it. It nearly worked, and probably would have if they realized earlier how to coordinate their efforts. But by 'nearly worked,' they also mean 'left the writers amusingly exhausted and without any dead gazelles.'

  6. As indicated previously, this pleased me greatly to hear--if only out of narcissist feelings for my own species.

  7. sleipnir_ says:

    There was an interesting documentary on the BBC a few years back taking a similar stance: provoking an animals flight response then catching up with it, provoking it again etc. until the animal died of exhaustion. being bipedal enable humans to carry things such as water and knives and what not. Makes sense once you think about it

  8. lrc says:

    There's a story about Richard Leakey, in his seventies, proposing this very theory. One of his grad student's didn't believe him, so the next morning he set out on foot to chase down a gazelle, returning that night with his prey slung over his shoulder.

    I may have missed some of the details, but that's the gist of it. It may be the same story referenced in one of the other comments.

  9. See Niven's short story, Table Manners.

  10. baconmonkey says:

    still apparently the hunting technique of the Bushmen of the Kalahari desert.

    that or it just means 2 million years ago, some people learned to explout the Matrix.

  11. gfish says:

    I think I'll stick with my atlatl. Weapon systems are here to stay.

  12. ferrouswheel says:

    Coincidentally I recently read an article about a tribe in South America whose members routinely run 80 km distances every week.

    The run on the balls of their feet and make use of the springy tendons Lieberman mentions. Most of the sports/running advice of today is all ass-backwards because they recommend you roll you foot from heel to toe, which in comparison is terribly inefficient and creates far more joint damage on impact. The same goes for running shoes, they cushion impact making you loose that kinetic energy.

    • jesus_x says:

      For the first 2 years of high school (and all my life before that) I was a tall lanky kid. But as a freshmen, my asthma cleared up, and thus my innate athletic ability was released, and I went out for track, short and mid length sprints. I did quite well too, and that's how I ran. The coach and some folks made fun of me until they saw me fly down the track. Watch the world's great sprinters, some of them do the same thing.

  13. ncongrunt says:

    I love the reference in the subject. One of my all time favorite movies.

  14. styxis says:

    This is neat and vaguely appropriate.
    Not time to make it pretty.

  15. mtbg says:

    Off-topic: You get a (very small) shout-out in today's xkcd -- see the south end of the easternmost island in the Blogipeligo.