Posted on 11/17/2004 11:06:41 AM PST by ElkGroveDan
LONDON (Reuters) - Humans were born to run and evolved from ape-like creatures into the way they look today probably because of the need to cover long distances and compete for food, scientists said on Wednesday.
From tendons and ligaments in the legs and feet that act like springs and skull features that help prevent overheating, to well-defined buttocks that stabilize the body, the human anatomy is shaped for running.
"We do it because we are good at it. We enjoy it and we have all kinds of specializations that permit us to run well," said Daniel Liberman, a professor of anthropology at Harvard University in Massachusetts.
"There are all kinds of features that we see in the human body that are critical for running," he told Reuters.
Liberman and Dennis Bramble, a biology professor at the University of Utah, studied more than two dozen traits that increase humans' ability to run. Their research is reported in the science journal Nature.
They suspect modern humans evolved from their ape-like ancestors about 2 million years ago so they could hunt and scavenge for food over large distances.
But the development of physical features that enabled humans to run entailed a trade off -- the loss of traits that were useful for being a tree-climber.
"We are very confident that strong selection for running -- which came at the expense of the historical ability to live in trees -- was instrumental in the origin of the modern human body form," Bramble said in a statement.
AGAINST THE GRAIN The conventional theory is that running was a by-product of bipedalism, or the ability to walk upright on two legs, that evolved in ape-like human ancestors called Australopithecus at least 4.5 million years ago.
But Liberman and Bramble argue that it took a few million more years for the running physique to evolve, so the ability to walk cannot explain the transition.
"There were 2.5 million to 3 million years of bipedal walking without ever looking like a human, so is walking going to be what suddenly transforms the hominid body?" said Bramble.
"We're saying 'no, walking won't do that, but running will."'
If natural selection did not favor running, the scientists believe humans would still look a lot like apes.
"Running has substantially shaped human evolution. Running made us human -- at least in the anatomical sense," Bramble added.
Among the features that set humans apart from apes to make them good runners are longer legs to take longer strides, shorter forearms to enable the upper body to counterbalance the lower half during running and larger disks which allow for better shock absorption.
Big buttocks are also important.
"Have you ever looked at an ape? They have no buns," said Bramble.
Humans lean forward when they run and the buttocks "keep you from pitching over on your nose each time a foot hits the ground," he added.
So how does micro-evolution keep from bleeding over to macro-evolution?
In the day we sweat it out in the streets of a runaway American dream
At night we ride through mansions of glory in suicide machines
Sprung from cages out on highway 9,
Chrome wheeled, fuel injected
and steppin' out over the line
Baby this town rips the bones from your back
It's a death trap, it's a suicide rap
We gotta get out while we're young
`Cause tramps like us, baby we were born to run
Wendy let me in I wanna be your friend
I want to guard your dreams and visions
Just wrap your legs 'round these velvet rims
and strap your hands across my engines
Together we could break this trap
We'll run till we drop, baby we'll never go back
Will you walk with me out on the wire
`Cause baby I'm just a scared and lonely rider
But I gotta find out how it feels
I want to know if love is wild
girl I want to know if love is real
Beyond the Palace hemi-powered drones scream down the boulevard
The girls comb their hair in rearview mirrors
And the boys try to look so hard
The amusement park rises bold and stark
Kids are huddled on the beach in a mist
I wanna die with you Wendy on the streets tonight
In an everlasting kiss
The highway's jammed with broken heroes on a last chance power drive
Everybody's out on the run tonight
but there's no place left to hide
Together Wendy we'll live with the sadness
I'll love you with all the madness in my soul
Someday girl I don't know when
we're gonna get to that place
Where we really want to go
and we'll walk in the sun
But till then tramps like us
baby we were born to run
You're in your four walls, O. The weather is fine outside.
But, for the sake of good old-fashioned dialogue, here goes:
If there was a Big Bang, why were there elements that would allow for the BB in the first place?
If life evolved, why don't I have the speed of a cheetah, the wingspeed of a hummingbird, the eyesight of the eagle, and the power of a lion?
If we're supposed to be constantly advancing in all aspects of evolutionary speciation, why is our intellect the only thing humans possess that is superior to the animal kingdom?
Why is there such a question as why? Animals don't ask this.
These will just get us started, if you wish. It gets more ponderous from here.
BTW, do you believe that the law of entropy applies to the cosmos, or just to the portions of it that favor evolution.
Isn't the 2nd Law supposed to be a Law, not an opinion?
Ironically, the characteristics that most strongly distinguish us from other animals, especially other primates, are seldom mentioned or considered in most of the commentaries we see. One such is our ability to run on two legs. Unlike our closest relatives, we do not merely scurry along for short distances with the help of our knuckles - we can race flat out for miles using only our legs and feet. A second characteristic is our nudity, our essentially furless bodies, tufted for the most part on the head and in the interstices of the limbs and the torso. A third characteristic is our ability to sweat profusely. Our boastful phrases "sweat like a pig" or "sweat like a horse" are essentially meaningless, since we sweat much more than either of these animals. Running, sweating and nudity were born of the African savanna, perhaps at the time that our ancestors moved out of the forests to become the slim and graceful Australopithicines. Out in the African sun, away from the trees, we needed to keep cool, hence our sweating, naked bodies, and we needed to protect the overactive brains that since have done such damage to our planet, hence our thatches of hair.Not surprisingly, sweating and bipedal running are two of the more important requirements for participation in marathons. And these, as Heinrich convincingly demonstrates, came about because of two other human qualities, the first being our need to hunt. Astonishing as this may sound to many in today's automated world, the human being can in fact outrun many other kinds of animals, among them members of the deer and antelope families. Heinrich cites a Navajo hunter named Yellowman who, after half a day of relentless chasing, could run a deer to the point of collapse, whereupon he would wrestle it to the ground and stifle it with his bare hands, holding a little sacred pollen in his palms so that the deer's last breath would be holy. The deer's unperforated hide would then be used in religious ceremonies.
In the recent past, Kalahari bushmen were also able to run down their prey - in the Kalahari Desert, the animals in question were antelopes - taking advantage of the heat of the day. The bushmen, thanks to their human physiology, could tolerate heat more easily than the antelopes, who are so elegantly designed that they are virtually independent of water, an excellent adaptation for a desert environment, but a disadvantage if one must outrun a human being. Instead of cooling themselves by drinking water or immersing themselves in it, they can let their body temperatures rise, yet must try to minimise the amount of heat that their bodies accumulate, to which end they spend the middle of the day standing quietly in the shade. A human runner who could never outsprint them can, by remorseless chasing and phenomenal endurance, eventually exhaust them.
Presumably, the marathon method of hunting is an ancient one, and it involves the second human attribute which, Heinrich believes, other animals probably lack - the ability to formulate and also to realise long-distance goals. "We are psychologically evolved to pursue long-range goals," he writes, "because through millions of years that is what we on average had to do in order to eat. To us, even an old deer that had not yet been caught would have required a very long chase. It would have required strategy, knowledge and persistence. Those hominids who didn't have the taste for the long hunt, as such, perhaps for its own sake, would very seldom have been successful. They left fewer descendants."
"Our ancient type of hunting - where we were superior relative to other predators - required us to maintain long-term vision that both rewarded us by the chase itself and that held the prize in our imagination even when it was out of sight, smell and hearing. It was not just sweat glands that made us premier endurance predators. It was also our minds fuelled by passion. Our enthusiasm for the chase had to be like the migratory birds' passion to fly off on their great journeys, as if propelled by dreams ...When [the hunter/runners] felt fatigue and pain, they did not stop, because their dream carried them still forward. They were our ancestors."
Don't piss off an Ostrich.
> You're in your four walls, O. The weather is fine outside.
Why do you think that? Got a direct line to the Great Old Gods? Maybe a hotline to Yog Sothoth? Is Cthulhu your pen-pal? Maybe getting weather reports from Outside by Azathoth his own self?
> If there was a Big Bang, why were there elements that would allow for the BB in the first place?
No idea.
> If life evolved, why don't I have the speed of a cheetah...
Because it would not be advantageous to. Everything costs; for a human to be as fast as a Cheetah they'd have to give up some other aspect.
> why is our intellect the only thing humans possess that is superior to the animal kingdom?
As I said... everything costs. And in the case of intellect, the costs of that were outweighed by the benefits. A lion could claw your ass in half in a millisecond. But you'd have to abandon your intellect to allow that to happen.
>Why is there such a question as why?
Because there are minds to ask it.
> Animals don't ask this.
Why do you think this? I have seen more than my share of mammals (cats, dogs and ferrets) that certainly seem to understand enough to wonder why. Sadly, it's generally wondering why the human they depend on is treating them so poorly.
Were you hurried in your reply?
It's not as prepared as I expected you to be.
Would you like to postpone this conversation for another time?
> do you believe that the law of entropy applies to the cosmos, or just to the portions of it that favor evolution.
Entropy will do it's thing across the cosmos...on cosmic time scales. While biological evolution is grindingly slow to the human mind, it is blisteringly fast compared to the lives of stars.
> Isn't the 2nd Law supposed to be a Law
It is, and it's being carried out. As the Sun powers interesting things on Earth, entropy grinds the Sun down. The combined *average* is entropy winning.
> It's not as prepared as I expected you to be.
Sometimes answers to deep philosphical questions of "why" really do have simple answers.
And those answers can be unfulfilling when the questions are vague or ill-thought-out.
Perhaps I confused the endurance of humans with the question of ability to catch an ostrich.
Interesting thought though, isn't it. Do you know if anybody has ever run down an ostrich or a pronghorn antelope?
See #106 above.
In a way, they do it often. It is called tracking...
"Sometimes answers to deep philosphical questions of "why" really do have simple answers."
Therefore, I assume, your answer of:
"> If there was a Big Bang, why were there elements that would allow for the BB in the first place?
No idea. "
And, your inability to see beyond the superficial aspects of the seen, and logically inferred, does nothing to dispel the possibility, or the reality of an alternate universe, a a spiritual dimension, or any of the other alternates that have been proposed from the same scientific community of physicists that power so many of the current trends of speculation on the beginnings of the universe.
Cynicism does not wear well on the human condition.
BTW, are you insinuating that my questions are ill-thought-out or vague? Shame on my illiterate self.
Of course Bushmen will not be hunting Pronghorns. But I suspect early Americans did much the same.
'Ppreciate that about African antelope, but pronghorn antelope have existed in North America only for millions of years. Ostriches, on the other hand.... could be descendants of the African swallow.
Coconuts, anyone?
LOL. Liked that.
Superior intellect. But superior physical attributes?
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