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.
What a specious theory this is...if evolution were to be as true as it's advocates would have us believe, then we have to bifurcate our logic and believe both:
That we don't have the strength, agility, and speed of apes because we evolved our minds to the point that we don't need those attributes any more; or
That we have evolved to be a speedy, running kind of being because of the shape of our buttocks, among other things.
The great part of being an evolutionist is that you are allowed by the complicit community of scientists, and the media, to posit whatsoever you choose, and it'll never be challenged, as long as you have Ph.D. at the end of your name.
No wonder Hitler was able to get away with Social Darwinism to the degree he did. We practise it today, too, but we're subtle enough not to admit it.
> we can carry a certain amount of food and/or water to sustain us, which the animal cannot
That and we can carry pointy sticks, which make the job at the end a lot easier...
I hate running.
> why haven't the other apelike critters that run evolved into our physical structure?
Because they fit nicely into the niche they were in. Humans and human ancestors found a new niche that was at the time unfilled, or at least open to exploitation.
> We are separated genetically from the other primates
Yes, that's what a few million years of divergent evolution will get you.
> we never can evolve beyond our limits
Correct. We evolve to current limits, and either prosper, perish, or evolve *around* those limits.
There is no "proof" in science. There is a preponderance of evidence, but proof never enters into it.
To the best of my knowledge, there is absolutely no proof of evolution occuring at the macro- level. We have observed it at the micro- level, as some species have undergone slight changes in color or size, but in the entire history of our observation of nature we have never ever witnessed, nor have evidence, one species completely changing into another.
The entire history of our (carefully recorded and scientifically analyzed) observation of nature has lasted, at the outside, 500 years (that's being generous). The sort of speciation to which you refer takes place over thousands or tens of thousands or hundreds of thousands (or more) of years (except at the microbial level).
Time is the key.
Why I fall down so much when I run. Padded in the wrong places.
If you have a toe and I have a toe then we must have come from some other one thing with a toe. It is not possible that we both came from Some Other Thing With a Toe because, well, that would require Capital Letters and ockham's razor requires us to write in all small letters if we can at all get by with it.
LOL ... me too, I've always said I'll take it up when I see a smiling jogger.
The timescales involved in evolution make actual observations of macroevolution unlikely. Obviously, the absence of evidence isn't evidence of absence, but it seems to me that if evolutionary discussions were predicated on concepts like "preponderance of evidence" and "reasonable doubt," it might be useful to those who are sincerely on the fence between evolution and literal creationism.
No one's observed it because it takes millions of years to change from one species to another. No one's ever observed any major climate change or continental drift either, yet we can be reasonably confident that both have occured in the past.
As far as I know, humans and wolves are the only long-distance running hunters. It's not speed, it's the ability to keep going for long periods of time that will wear out the prey. And it requires the ability to remain focused on the objective. It's been said that these characteristics are one of the reasons we get along so well with dogs. We're the same kind of hunters.
Hm - a LOT of similarities. I weigh about 185 and try to jog three times a week (Mon, Thu, Sat). But I only run 25 minutes or so, about a third of that running up and down a pretty steep hill a few blocks from my house. So I would imagine that it is equivalent to running about three miles or so. I exercise (moderate weights, calesthentics) right before I run. I think this helps to stretch out the muscles, warm them up, and thus preclude injury.
Then Jimmy the Greek was right!
Is Ockham's razor why we can shave, and other mammals can't?
Although I believe that the existence of Rainbow Monkey butts proves that we don't actually have to shave to be smooth skinned.
Hmmm, I seem to have caught myself in a penumbral conundrum.
Dog to run
Bird to fly
Man to sit and wonder why
At least not the majority of us who are clinically obese (Body Mass Index > 25).
Actually, we do! Human beings can out accelerate sports cars for the first ten feet or so. I think we're the fastest two-leged creatures on earth. I think.
Well this shows that you don't fully understand the processes that cause the descendants of species to gradually retain or lose characteristics over time, or the lengths of time involved. Yes it does sound silly when you try to imagine one species, "changing into another" but that's not what happens.
The process that has created the myriad of amazing life forms on this planet is a wondrous gift from our Creator, and it fits perfectly within my deeply held Christian Faith.
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