Big butt? Here's why.

December 12, 2005 1:44 AM

Why Homos have big butts, short shouts, and big leg joints: long distance running.
posted by orthogonality (36 comments total)

Er, snouts.
posted by orthogonality at 1:45 AM on December 12, 2005

Your post is certainly suggestive.
posted by Colloquial Collision at 2:03 AM on December 12, 2005

I read short shorts on my first try. Those Homos!
posted by srboisvert at 4:38 AM on December 12, 2005

Short shout out to all my homos!
posted by rxrfrx at 4:55 AM on December 12, 2005

Who cares about the big leg joints, I want to know about homos and the short shorts.
posted by Plutor at 5:08 AM on December 12, 2005

This reminds me of a story on This American Life about trying to kill antelope by chasing them until they collapse. The theory was that most animals can only run for short periods of time, but if caught in a prolonged chase by long-distance running humans they would overheat.
posted by Alison at 5:38 AM on December 12, 2005

I'm almost positive this is a double, but maybe I just read it when it came out a year ago. Since I run, it is likely.
posted by sciurus at 6:10 AM on December 12, 2005

story on This American Life

That story was hilarious. For those who didn't hear it - it didn't work. Clearly, on the ancient savannahs of africa, early captured animals for food by the use of their wits and dexterity, not astounding speed.

This is neat. It bears out my completely subjective sensation when I'm out on a good run: This is what the human body is built to do well.
posted by Miko at 6:20 AM on December 12, 2005

Yeah, I love this theory of human evolution. I'm a runner because I'm human.

Incidentally, there is a great book by a great naturalist, scientist and UVM prefessor Bernd Heinrich. Why We Run is the title of the book. Heinrich was one of our (USA) best ultrarunners, and once held the US 100 mile record.
posted by OmieWise at 6:36 AM on December 12, 2005

My knees beg to differ.
posted by kika at 6:37 AM on December 12, 2005

Thanks for the link. I remember reading a condensed version of this theory some time last year, but it wasn't as comprehensive. I'm hardly an objective judge of the validity of this finding, since I am forever trying to add to my arsenal of responses to people who feel compelled to explain to my gimpy self that the reason we retired distance runners have aches and pains as we get older is because "the body was never designed to run long distances".
posted by stagewhisper at 7:00 AM on December 12, 2005

OmieWise writes "prefessor"

I'm sorry, of course that's *perfessor*.
posted by OmieWise at 7:03 AM on December 12, 2005

I like big glutei maximi and short femoral necks and I cannot lie.
posted by horsewithnoname at 7:04 AM on December 12, 2005

This ScienceDaily article came up a couple of months ago in the comments to an Ask Mefi question: What are humans best at? The discussion also linked to a related article at ABC news.
posted by RichardP at 7:09 AM on December 12, 2005

I'm pretty sure I also saw this or something just like it here on the blue a couple months ago. But I don't remember this particular turn of phrase:

endurance running evolved in human ancestors so they could pursue predators

Interesting theory. What, were they so hard up for entertainment that they needed to run after and taunt their predators?
posted by soyjoy at 7:13 AM on December 12, 2005

soyjoy wrote: "What, were they so hard up for entertainment that they needed to run after and taunt their predators?"

Iraq? /flee
posted by cleverusername at 8:00 AM on December 12, 2005

Er, what if one resembles the one on the left more than the one on the right? Just asking, not that it's relevant to me or anything (looks wistfully at place where he's heard arches should be).
posted by QuietDesperation at 8:18 AM on December 12, 2005

The article makes clear that its not short distance speed that humans are good at, but long distance endurance. How does long distance endurance tie into hunting? Hunters need to go to where the animals are migrating .. the African savanna is like the mid-western plains of North America, large herds of grass-feeding animals on the constant move across vast distances. Keeping up with the herd may be what its all about. Just a thought.
posted by stbalbach at 8:21 AM on December 12, 2005

Get back up that tree, QD!
posted by Joeforking at 8:24 AM on December 12, 2005

Yeah, stbalbach, there's definitely something missing there. I don't see how long distance endurance is going to make somebody a better hunter. The scavenging bit is a stretch. When you see a column of vultures you're no longer talking about the distances involved for long distance running. And his dismissal of bipedalism is also a bit off. It could very well be the case that anatomically correct humans evolved slowly yet the bipedal ability--particularly walking all the time and rarely climbing trees--would still be the turning point.
posted by nixerman at 8:36 AM on December 12, 2005

Keeping up with the herd may be what its all about.

In the USA, at least, even in the colder states, there are plenty of animals that don't migrate all that far (for example deer), that would be easy to hunt without long distance running.
posted by dial-tone at 8:52 AM on December 12, 2005

Ummm....chasing mates? Just trying to add sexual selection into the mix here. Still doesn't explain the Homos, though.
posted by kozad at 8:57 AM on December 12, 2005

I don't see how long distance endurance is going to make somebody a better hunter.

Consider the Cape Hunting Dog: By some measures (e.g., pursuit to kill ratio), the most successful mammalian predator known to man. They can sustain high speeds for ungodly distances, and so can outrun prey with significantly faster top speeds. And they hunt in well-organized packs, so they can outmanouver their prey, too.

Here's the problem: They prey know this, and they have gotten very good at spotting Cape Dogs a very long distance away.

So what the Cape Dogs do is move. All the time. They move at a steady run all day long, in order to close in on their prey fast enough that they can open the faucet and run them down once they get in range.

Wolverines do an analogous thing: They cover enormous amounts of territory (40 miles or more, as I recall) in a single day, as a strategy for finding prey that doesn't see them coming. (I saw a video of it one time, from the air. It's kind of a hoot, because they don't look like they can run very well, but apparently they don't care how awkward they look.)

In other words, it could be an advantage because it allows them to encounter a greater number of prey opportunities in a give unit of time.
posted by lodurr at 9:04 AM on December 12, 2005

This ScienceDaily article came up a couple of months ago in the comments to an Ask Mefi question: What are humans best at?

That's where I saw it!
posted by sciurus at 9:04 AM on December 12, 2005

Another possibility is that early humans and their immediate ancestors ran to scavenge carcasses of dead animals – maybe so they could beat hyenas or other scavengers to dinner, or maybe to "get to the leftovers soon enough," Bramble says....Scavenging "is a more reliable source of food" than hunting

I think this bears serious consideration. IANAEvolutionary Biologist, but I think much too much is made of the idea of "Man, the Predator." Most of the lay science reading I've done suggests that early humans did a lot more gathering and scavenging than hunting, and that when they did hunt, a lot more fishing and trapping than spear- and rock-throwing. We're just not all that tough compared to real predators, and when we outcompeted them, it through brains and the ability to eat omnivorously, not so much brawn.

I like the idea of being able to stay with a migrating herd of ungulates, though. Makes good sense.

In the USA, at least, even in the colder states, there are plenty of animals that don't migrate all that far (for example deer), that would be easy to hunt without long distance running.

I don't think it works well to extrapolate from present-day animal behavior in the USA. The climate and wildlife ecosystem was a little bit different even not so long ago (Wisconsin glacier and all), and seasonal migrations of herding animals were much longer. Anyway, when early humans were emerging, they weren't doing it in North America. You'd have to look at animal populations and behavior in Africa more than four million years ago to guess at what the challenges of hunting were.
posted by Miko at 9:13 AM on December 12, 2005

Re. scavanging v. hunting: Predators seldom make such a clean distinction, themselves. Hyaenas get most of their calories from hunting, but do a lot of scavenging. Lions get a surprising amount of their calories from scavenging.

Pure scavengers are rare, too. By definition, a scavenger eats what's available, and that generally includes live prey that's easy to catch.

So though we have aesthetic baggage around saying our ancestors were scavengers, it would be foolish to suppose that htey weren't, at least at some level.
posted by lodurr at 9:17 AM on December 12, 2005

Plus distance running extends your territory, ups your odds of finding something to hunt or scavenge.
My body gives me all kinds of “YES!” signs when I run long distances. That can’t be a coincidence. Those opiates have to be an adaption as well.
posted by Smedleyman at 10:51 AM on December 12, 2005

I can't wait to see how our bodies evolve now that all we do is sit on our asses.
posted by Robot Johnny at 11:11 AM on December 12, 2005

Robot Johnny wins!

Isn't this all a part of the ID (Inferior Design) argument?
posted by nofundy at 11:30 AM on December 12, 2005

I think this makes some sense. If you're a hungry group of folk creeping up on a herd of antelope or somesuch, it might not make sense to just try picking one and running it down. It's also unlikely that you'll be able to make a quick clean kill with the rocks and sticks you have for weapons. But if you're intelligent enough to get organised, creep up on your prey and attack it enough to injure it, and then spend the next few hours or so following it in its weakened state until you can attack it again or it collapses, you'll eventually get to eat it. Being able to run, albeit relatively slowly, for long distances would be a big advantage in such a scenario.
posted by normy at 11:50 AM on December 12, 2005

I don't see how long distance endurance is going to make somebody a better hunter.

Me neither. I just figured that we were running away. The fact that the hunter-gatherers were eventually killed by the farmers makes me think that perhaps we were in a bloody coevolutionary war that we won by running away (and eventually freeing time via agriculture to develop better killing weapons.)

On preview: good point, normy.

I can't wait to see how our bodies evolve now that all we do is sit on our asses.

Isn't this what people talk about when they discuss agriculture as the biggest mistake in human history? Jared Diamond maybe ... I'm too lazy to look it up.
posted by mrgrimm at 12:00 PM on December 12, 2005

This was a "double" for me in that I remembered this theory from my 200-level ecology & evolution class...then I read the article. Same school, same professor, and that was ~7 years ago.

One thing I vaguely remember from this theory that wasn't in the article was that hair loss in humans (i.e., from most of our body, not from our heads ;) ) had the effect of streamlining humans for running.
posted by artifarce at 12:03 PM on December 12, 2005

Thirty or so years ago, it was popular to guess hypothesize that humans evolved through swimming.
posted by dhartung at 12:17 PM on December 12, 2005

I can't wait to see how our bodies evolve now that all we do is sit on our asses.

But we're already set up for it! Big butts make a nice cushion, and the short snouts keep us from bumping into the monitor.
posted by Durhey at 12:32 PM on December 12, 2005

those who enjoyed the scott carrier's NPR story on chasing antelope should most definitely pick up the book-- Running After Antelope. it's a fun read.
posted by jcruelty at 3:42 PM on December 12, 2005

That was never a particularly mainstream theory, as far as I know, dhartung, although it did gain a certain amount of pop appeal for a while. But it doesn't take much to show that humans aren't particularly well set up for swimming ... our noses and feet are all wrong for it, among other things.
posted by kyrademon at 8:59 PM on December 12, 2005