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.
> Perhaps you have greater faith in the human calculator than do I.
I'm an engineer. We have "faith" in figures because the proper application of them gives repeatable and reliable results. There is very little room in engineering for "faith" in the religious sense. If your upper stage has an engine with a specific impulse of 450 seconds and you have a mass ratio of 90%, it does not matter how much faith you have... you will not generate more than 10.16 kilometers per second of delta v in free space.
Biology is nothing more than *extremely* complex physics and chemistry. The equations are horribly complex, vastly detailed and poorly understood; we do not as yet have the knowledge to calculate the biological world with the accuracy we can for, say, a bridge. Nevertheless, we have enough of the math down that we can figure out some of the basic trends.
Gods, on the other hand, cannot be calculated.
One of the theories surrounding the relationship between man and dogs is the fact that they both were able to "run/trot" all day long while hunting, something that most predators can't do. In theory this led them to be good hunting partners using the human brain and eyesight and the dogs sense of smell to track and capture prey.
I've heard that ostriches can do something like 45 miles per hour, double a world-class human sprinter.
Sure, and when you apply Halpin-Tsai equations to determine ply in composite materials properly, you don't kill operators at molding machines, you don't endanger the end user of such products, and on the whole, you make the world a better place with plastics.
So?
I've been in engineering, and practical applications of engineering, all my work life, and I have yet to find a single engineer who is able to answer the question: Why?
Who, when, what, where, how, are well within their realm. But why is in the realm of God. If someone is bound to the four walls of the senses, it's impossible to even know how to ask the question: Is there weather outside?
BTW, your website's kind of interesting.
The third world record held by Ostriches is the land speed record for a bird. Ostriches use running to escape danger so it is good for them to be able to run quickly. They have been timed running at 72 kph (45 mph) non-stop for 15-20 minutes during which time they travelled over 15 miles and left any predators well behind.
"same kind of hunters" Good point never thought of that. I have not read the whole thread but have not seen sweat mentioned. Very few animals horses, humans and very few others that I don't recall sweat. Allows us to run in warm or hot temps without overheating. Dogs don't sweat except at the paws they mainly cool down by panting. Dogs and other pack animals usually hunt with a relay system one or more keeps up the chase while others rest. Humans and horses can cover lots of ground and can move away from predators (or to better food/water supply) unless the attack is very sudden.
What do you mean by long distance? 30 or 40 miles? I seriously doubt that any land bound creature alive can outrun a human at distances of 50 miles or more. The human body is built for fabulous endurance. The Tarahumara indians were noted for their fantastic endurance and the ability to cover unbelievable distances in a days time.
Anyone who is familiar with the differences between male and female skeletons can see that it is unlikely that women were "born to run".
Running is hard on the knees. Try blading. :-)
Not to mention the fact that our neolithic ancestors did not have sports bras.
My theory on Evolution is that Darwin was adopted. -Mad Dawgg P.H.D.
> I have yet to find a single engineer who is able to answer the question: Why?
"Why" what? You need to be more specific. "Why is X," or "Why do you Z?"
> Who, when, what, where, how, are well within their realm. But why is in the realm of God.
And that's fine. Maybe "Why = God." But then, that does not even remotely come close to refuting "how = evolution" and "when = four billion years ago."
> your website's kind of interesting.
Just wait till I refurb the thing.
The best of human endeavor in a 26 mile marathon is a little over 2 hours. An ostrich has been clocked at 45 mph over twenty minutes= 15 miles. It would take the human 1 hour at a world class marathon runner's pace to catch up to the ostrich if it stopped and stood still for an hour or so.
The odds of human success? About the same as the Dolphins chance of winning the Super Bowl.
About the pronghorn antelope: don't know the endurance, mileage wise. I'll try to find out.
> So assumes the evolutionist.
It's not an assumption, but a deduction based on the evidence.
> It could also be that the genetic lines were separate at their creation, that we did not evolve from some singular, original life form.
Yes, yes, we're all living in The Matrix. God built the planet old for some reason.
> Entropy would suggest that, given the variables and chances, life would have devolved from that original life form, rather than having evolved.
Incorrect. For this to have any semblence of accuracy, you would have to believe that Earths biosphere is a closed system. It is not.
They present some of the physiological and behavioral characteristics of dogs in a somewhat different light. In fact, the authors dispute the usual "dog-as-a-tame-wolf" concept in some respect.
If you're interested in dogs, as I am, I recommend it.
> Not to mention the fact that our neolithic ancestors did not have sports bras.
Or manzierres...
Disclaimer: Opinions posted on Free Republic are those of the individual posters and do not necessarily represent the opinion of Free Republic or its management. All materials posted herein are protected by copyright law and the exemption for fair use of copyrighted works.