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Hannahrain
08-09-2007, 08:51 AM
http://news.yahoo.com/s/ap/20070808/ap_on_sc/human_evolution

Fossils challenge old evoluton theory

By SETH BORENSTEIN, AP Science Writer Wed Aug 8, 5:57 PM ET
WASHINGTON

Surprising research based on two African fossils suggests our family tree is more like a wayward bush with stubby branches, challenging what had been common thinking on how early humans evolved.

The discovery by Meave Leakey, a member of a famous family of paleontologists, shows that two species of early human ancestors lived at the same time in Kenya. That pokes holes in the chief theory of man's early evolution — that one of those species evolved from the other.

And it further discredits that iconic illustration of human evolution that begins with a knuckle-dragging ape and ends with a briefcase-carrying man.

The old theory is that the first and oldest species in our family tree, Homo habilis, evolved into Homo erectus, which then became human, Homo sapiens. But Leakey's find suggests those two earlier species lived side-by-side about 1.5 million years ago in parts of Kenya for at least half a million years. She and her research colleagues report the discovery in a paper published in Thursday's journal Nature.

The paper is based on fossilized bones found in 2000. The complete skull of Homo erectus was found within walking distance of an upper jaw of Homo habilis, and both dated from the same general time period. That makes it unlikely that Homo erectus evolved from Homo habilis, researchers said.

It's the equivalent of finding that your grandmother and great-grandmother were sisters rather than mother-daughter, said study co-author Fred Spoor, a professor of evolutionary anatomy at the University College in London.

The two species lived near each other, but probably didn't interact, each having its own "ecological niche," Spoor said. Homo habilis was likely more vegetarian while Homo erectus ate some meat, he said. Like chimps and apes, "they'd just avoid each other, they don't feel comfortable in each other's company," he said.

There remains some still-undiscovered common ancestor that probably lived 2 million to 3 million years ago, a time that has not left much fossil record, Spoor said.

Overall what it paints for human evolution is a "chaotic kind of looking evolutionary tree rather than this heroic march that you see with the cartoons of an early ancestor evolving into some intermediate and eventually unto us," Spoor said in a phone interview from a field office of the Koobi Fora Research Project in northern Kenya.

That old evolutionary cartoon, while popular with the general public, is just too simple and keeps getting revised, said Bill Kimbel, who praised the latest findings. He is science director of the Institute of Human Origins at Arizona State University and wasn't part of the Leakey team.

"The more we know, the more complex the story gets," he said. Scientists used to think Homo sapiens evolved from Neanderthals, he said. But now we know that both species lived during the same time period and that we did not come from Neanderthals.

Now a similar discovery applies further back in time.

Susan Anton, a New York University anthropologist and co-author of the Leakey work, said she expects anti-evolution proponents to seize on the new research, but said it would be a mistake to try to use the new work to show flaws in evolution theory.

"This is not questioning the idea at all of evolution; it is refining some of the specific points," Anton said. "This is a great example of what science does and religion doesn't do. It's a continous self-testing process."

For the past few years there has been growing doubt and debate about whether Homo habilis evolved into Homo erectus. One of the major proponents of the more linear, or ladder-like evolution that this evidence weakens, called Leakey's findings important, but he wasn't ready to concede defeat.

Dr. Bernard Wood, a surgeon-turned-professor of human origins at George Washington University, said in an e-mail Wednesday that "this is only a skirmish in the protracted 'war' between the people who like a bushy interpretation and those who like a more ladder-like interpretation of early human evolution."

Leakey's team spent seven years analyzing the fossils before announcing it was time to redraw the family tree — and rethink other ideas about human evolutionary history. That's especially true of most immediate ancestor, Homo erectus.

Because the Homo erectus skull Leakey recovered was much smaller than others, scientists had to first prove that it was erectus and not another species nor a genetic freak. The jaw, probably from an 18- or 19-year-old female, was adult and showed no signs of malformation or genetic mutations, Spoor said. The scientists also know it isn't Homo habilis from several distinct features on the jaw.

That caused researchers to re-examine the 30 other erectus skulls they have and the dozens of partial fossils. They realized that the females of that species are much smaller than the males — something different from modern man, but similar to other animals, said Anton. Scientists hadn't looked carefully enough before to see that there was a distinct difference in males and females.

Difference in size between males and females seem to be related to monogamy, the researchers said. Primates that have same-sized males and females, such as gibbons, tend to be more monogamous. Species that are not monogamous, such as gorillas and baboons, have much bigger males.

This suggests that our ancestor Homo erectus reproduced with multiple partners.

The Homo habilis jaw was dated at 1.44 million years ago. That is the youngest ever found from a species that scientists originally figured died off somewhere between 1.7 and 2 million years ago, Spoor said. It enabled scientists to say that Homo erectus and Homo habilis lived at the same time.

kreutz2112
08-09-2007, 09:04 AM
"This is not questioning the idea at all of evolution; it is refining some of the specific points," Anton said. "This is a great example of what science does and religion doesn't do. It's a continous self-testing process."


Thank you...good article hannah.

Hannahrain
08-09-2007, 09:07 AM
That caused researchers to re-examine the 30 other erectus skulls they have and the dozens of partial fossils. They realized that the females of that species are much smaller than the males — something different from modern man, but similar to other animals, said Anton. Scientists hadn't looked carefully enough before to see that there was a distinct difference in males and females.

Difference in size between males and females seem to be related to monogamy, the researchers said. Primates that have same-sized males and females, such as gibbons, tend to be more monogamous. Species that are not monogamous, such as gorillas and baboons, have much bigger males.


I thought this was really interesting in particular.

Yablonowitz
08-09-2007, 09:24 AM
I thought this was really interesting in particular.

As I suspected all along, size does matter.

fatbastard
08-09-2007, 10:05 AM
Aren't there any other archaeologists beside the Leakeys? Their house must be really dusty.

mob roulette
08-09-2007, 06:06 PM
Aren't there any other archaeologists besides the Lakers? Talk about not letting go of the past.

J~$$$
08-09-2007, 09:03 PM
Dear Menik,

http://uk.reuters.com/article/scienceNews/idUKL0888871120070809

Alchemy
08-09-2007, 09:03 PM
Maybe we are the result of Homo habilis and Homo erectus. Hmmm...

mountmccabe
08-09-2007, 09:09 PM
Maybe we are the result of Homo habilis and Homo erectus. Hmmm...

If that were possible (I'm guessing you mean the interbreeding of those two species resulted in Homo sapiens, at least eventually) then they wouldn't be separate species. Sayin'.

Alchemy
08-09-2007, 09:24 PM
They'd be capable of breeding though, wouldn't they? Some anthropologists suggest that Neanderthalis and Sapien sapiens might have bred with eachother and that has resulted in some of the Europeans that live today.

miscorrections
08-09-2007, 09:27 PM
when different species breed either you get no offspring or in rare cases there is offspring but it's sterile.

that's the def. of species, yo.

Alchemy
08-09-2007, 09:29 PM
when different species breed either you get no offspring or in rare cases there is offspring but it's sterile.

that's the def. of species, yo.

But, were they different species because we thought they didn't live at the same time?

mountmccabe
08-09-2007, 09:29 PM
If a significant amount of inter-breeding were possible they wouldn't be separate species. That's what separates species one from the other.


EDIT: Crosspost with Corrina

jackstraw94086
08-09-2007, 10:53 PM
These paleontologists waste so much time trying to carbon date ancient fossils and basically make educated guesses as to the ages of primitive man when they could just go to Missoula and thumb through birth certificates.

Alchemy
08-10-2007, 08:45 AM
If a significant amount of inter-breeding were possible they wouldn't be separate species. That's what separates species one from the other.


EDIT: Crosspost with Corrina

Yes, I know that seperate species can't breed. However, seeing that Homo habilis and Homo erectus now lived together (assuming its all official), doesn't that change things. I mean, we really don't know a lot about the breeding of these two "species". We can only really get information like eating habits due to jaw and teeth formations, sizes of their brains, their postures and relative size. Is the reason that both were considered seperate species due to the fact that we believed they did not co-exist?

If they are now able to live together, as Neanderthalis and Sapien did, wouldn't they have the possibility of breeding?

jackstraw94086
08-10-2007, 09:52 AM
Is the reason that both were considered seperate species due to the fact that we believed they did not co-exist?
um no, they were not considered different only because we thought they didn't coexist. They ARE considererd different species because the seem to be shaped differently and probably behaved differently.


seeing that Homo habilis and Homo erectus now lived together (assuming its all official), doesn't that change things.

actually it does. If they both lived at the same time in the same place then one cannot have evolved from the other. It's not as though there were Erectus families millions of years more evolved than the Habilis families living down the block if they did evolve from one another.



If they are now able to live together, as Neanderthalis and Sapien did, wouldn't they have the possibility of breeding?
possibly, but that's not how nature works. Grizzlies and Black Bears are evolutionarily very similar, but do you see them fucking each other often? It's seems you believe they were extremely similar, as if you're analogizing habilis/erectus sex to something like "jungle fever". They were different species from what some very smart people believe. They werent exactly the same shape, they ate very different foods, etc. It would probably be like gorrilas and orangutans fucking. Get your mind out of the gutter, you perv.

amyzzz
08-10-2007, 12:09 PM
Grizzlies and Black Bears are evolutionarily very similar, but do you see them fucking each other often?
I don't know about grizzlies and black bears, but there was that one grizzly/polar bear hybrid some hunter bagged last year....

Jenniehoo
08-10-2007, 02:41 PM
It's a flag waving day for supporters of Creationism.

Alchemy
08-10-2007, 04:35 PM
um no, they were not considered different only because we thought they didn't coexist. They ARE considererd different species because the seem to be shaped differently and probably behaved differently.

actually it does. If they both lived at the same time in the same place then one cannot have evolved from the other. It's not as though there were Erectus families millions of years more evolved than the Habilis families living down the block if they did evolve from one another.

possibly, but that's not how nature works. Grizzlies and Black Bears are evolutionarily very similar, but do you see them fucking each other often? It's seems you believe they were extremely similar, as if you're analogizing habilis/erectus sex to something like "jungle fever". They were different species from what some very smart people believe. They werent exactly the same shape, they ate very different foods, etc. It would probably be like gorrilas and orangutans fucking. Get your mind out of the gutter, you perv.

There was supposed to be a question mark after I said, "Doesn't that change things."

First of all, gorillas and orangutans are miles apart from eachother. If habilis and erectus were a walking distance apart at the same time, they may be as similar as neanderthalis to sapien. Also, I assure you that it is under legitimate study that neanderthalis and sapiens may have bred with eachother. In fact, I think it was the late Gould who said that when he looks at British people, he is looking at Neanderthal and Sapien children. Neanderthalis and sapiens were different shapes, had different brain sizes (which is heavily thought to be the reason why neanderthalis went extinct due to competition with sapiens), and of course, different habits. You'd be stupid, however, to compare neanderthalis and sapiens to gorillas and chimps or any other ape clearly off their branch (pun intended). Habilis and erectus were not that much different. What mainly makes all of those ancestors different were their brains sizes and tools. Ask any anthropologist, and they will tell you that the key change in our ancestor's evolution was the growth of intelligence. Habilis is called "handy man" because of their advancement in tool craft. Erectus is very similar to habilis, except that erectus is smarter. It is very possible for them to bred if they are in walking distance. My mind is not in the gutter. I'm actually minoring in Anthropology, and have taken classes on this. It's not so stupid to think about this as you think.

I'm just wondering if the differences between habilis and erectus are more than neanderthalis and sapiens, especially now that they may have co-existed in walking distances. Maybe sapiens and/or neanderthalis were off-spring of erectus and habilis? There is nothing perverted about that.

Alchemy
08-10-2007, 05:01 PM
By the way, here is a .pdf file (http://www.aseanbiotechnology.info/Abstract/21020590.pdf) about neanderthalis and sapiens engaging in "jungle fever" sex. 5% of you Europeans and West Africans might be a result of that. Studies still await an answer though.

It is unsure if Neanderthals are to be Homo neanderthalis or Homo sapien neanderthalis. So you see, these issues pop from time to time. Just because we think things are different species, doesn't mean they actually are.

clarky123
08-10-2007, 05:04 PM
By the way, here is a .pdf file (http://www.aseanbiotechnology.info/Abstract/21020590.pdf) about neanderthalis and sapiens engaging in "jungle fever" sex. 5% of you Europeans and West Africans might be a result of that. Studies still await an answer though.

It is unsure if Neanderthals are to be Homo neanderthalis or Homo sapien neanderthalis. So you see, these issues pop from time to time. Just because we think things are different species, doesn't mean they actually are.

Yes, you are an eggplant.

clarky123
08-10-2007, 05:07 PM
I hate people that open their mouths without thinking. If we were either idiot we wouldnt be able to read.

Alchemy
08-10-2007, 05:17 PM
I hate people that open their mouths without thinking. If we were either idiot we wouldnt be able to read.

It doesn't mean that you are going to be habilis or erectus, genius. I assure you, you are far from being habilis or erectus. I was only suggesting a small posibility of another line in ancestry that could have led to us, if we are going to remove erectus or habilis from our line of ancestry. We must have come from one of them (probably erectus). I am just saying that if they were as similar as neanderthalis and sapiens, maybe the next step was a result of both. Personally, I'm leaning towards erectus being in our ancestry, and habilis being kicked out of our line. I mean, we were least like habilis to begin with.

thefunkylama
08-10-2007, 05:19 PM
God damnit where are the pics

mountmccabe
08-10-2007, 08:30 PM
5% of you Europeans and West Africans might be a result of that.

http://i74.photobucket.com/albums/i269/mountmccabe/Coachella/de3a7b26.jpg

rage patton
08-11-2007, 01:10 AM
Darwin didnt even believe his own theory.

Thank you for this article Hannah.

Last semester, I tried convincing my psychology TA that evolution isnt a black and white issue and that there are many holes and flaws in the theory. She basically told me I was wrong and evolution is the be all and end all of todays modern science. Guess I will have to go talk to her again next semester...

theburiedlife
08-11-2007, 02:17 AM
All this means is either:

A) Homo Habilis has been coexisting with Erectus by descending from a common ancestor, and that the link in the evolutionary chain between them has not been discovered yet.
or
B) Erectus genetically broke away from Habilis and eventually competed with Habilis.
or
C) God Flipped a switch, and BAM, 6000 year old fossils.

mountmccabe
08-11-2007, 02:48 PM
Darwin didnt even believe his own theory.

Thank you for this article Hannah.

Last semester, I tried convincing my psychology TA that evolution isnt a black and white issue and that there are many holes and flaws in the theory. She basically told me I was wrong and evolution is the be all and end all of todays modern science. Guess I will have to go talk to her again next semester...

What Darwin did or did not believe is irrelevant. Science doesn't work that way.

And today's Darwinism is really a NeoDarwinism; no one actually believes that it is just as he wrote it up in The Origin of Species. This, also, is irrelevant to the truth of the theory of evolution. Science doesn't work that way.

The theory of evolution is true just as gravitational theory and atomic theory are true. That is how science works.

There are details and questions about which ancestors did what and where and to whom. There are unknowns and discussions and questions and disagreements even amongst people who study it for a living and know what the hell they're talking about. This is how science works.

kreutz2112
08-11-2007, 02:50 PM
amen

mountmccabe
08-11-2007, 03:09 PM
Hehe.

RotationSlimWang
08-11-2007, 03:18 PM
What Darwin did or did not believe is irrelevant. Science doesn't work that way.

And today's Darwinism is really a NeoDarwinism; no one actually believes that it is just as he wrote it up in The Origin of Species. This, also, is irrelevant to the truth of the theory of evolution. Science doesn't work that way.

The theory of evolution is true just as gravitational theory and atomic theory are true. That is how science works.

There are details and questions about which ancestors did what and where and to whom. There are unknowns and discussions and questions and disagreements even amongst people who study it for a living and know what the hell they're talking about. This is how science works.

What do you mean by "gravitational theory," exactly? Are you trying to imply that science has any means of explaining how gravity works, because it doesn't. Gravity is an observed relationship and nothing more.

To tell the truth, evolution has always seemed dubious to me. But probably mostly because I find it hard to believe that time actually moves in one direction all the time.

Alchemy
08-11-2007, 03:31 PM
What do you mean by "gravitational theory," exactly? Are you trying to imply that science has any means of explaining how gravity works, because it doesn't. Gravity is an observed relationship and nothing more.

To tell the truth, evolution has always seemed dubious to me. But probably mostly because I find it hard to believe that time actually moves in one direction all the time.

Everything in science is an observed relationship. Science is willing to except the fact that one day somebody might prove that gravity is not what we thought. However, we can be pretty damn sure that we understand gravity.

I think he meant that we are as comfortable with out observations on evoultion, as we are on our observations on gravity. We know that if we walk off a skyscraper, it's down to the ground for us. Science rests that same faith on evolution.

RotationSlimWang
08-11-2007, 03:35 PM
How can you say that we understand gravity when it defies all the principles of energy? It is, in fact, the most prominent factor of our physical world and yet it challenges our entire concept of how physics works.

Alchemy
08-11-2007, 03:39 PM
How can you say that we understand gravity when it defies all the principles of energy? It is, in fact, the most prominent factor of our physical world and yet it challenges our entire concept of how physics works.

Are you saying that there is no attractive force in any object which we can understand? How the Hell do we understand chemistry then? How about geology? I think the fact that scientists are willing to call gravity a law shows that they are very comfortable with gravity and not your fringe outlook on gravity.

RotationSlimWang
08-11-2007, 03:42 PM
What I am saying is that gravity is a force produced without fuel. It defies the energy efficiency principle. It establishes that mass exerts force on other masses but somehow without any actual process. Inanimate matter, generating and exerting energy/force, without any established explanation of by what means it does so.

Alchemy
08-11-2007, 03:48 PM
What I am saying is that gravity is a force produced without fuel. It defies the energy efficiency principle. It establishes that mass exerts force on other masses but somehow without any actual process. Inanimate matter, generating and exerting energy/force, without any established explanation of by what means it does so.

There are a lot of aspects of gravity, and so many theories rolling around each one. Yeah, we don't understand everything about gravity, but you'd be kidding yourself to say that it doesn't exist. There are still attracting forces, regardless of how they got there, that are at work. We know a lot about the attraction though, enough to work with it, and there is so much that we have been able to make use of it. You can't say that gravity doesn't exist just because you don't know how it begins. That's a major no-no in science. Scientist are pretty sure that there is an attractive force in objects. The same way they are pretty sure evolution exists. By the way, by pretty sure, I mean really really really sure.

RotationSlimWang
08-11-2007, 03:52 PM
When did I ever say it doesn't exist? Of course it fucking exists, shithead. You can see the relationship at play. Witnessing gravity at work and evolution at work are two very, very different things.

Alchemy
08-11-2007, 03:55 PM
When did I ever say it doesn't exist? Of course it fucking exists, shithead. You can see the relationship at play. Witnessing gravity at work and evolution at work are two very, very different things.

Well nobody said they had the same workings either, smartass. We are just saying that as positive as we are that gravity exists (which you believe also), we are just as positive that evolution exists. I don't know why you confuse it with the way they work.

RotationSlimWang
08-11-2007, 03:56 PM
We're not remotely as positive that evolution exists--actual scientists (not just creationists or ID scientists) doubt some of the supposed truths of evolution. Truth. Very few people doubt that things fall. Anyways, I'm off for the day.

Alchemy
08-11-2007, 04:05 PM
We're not remotely as positive that evolution exists--actual scientists (not just creationists or ID scientists) doubt some of the supposed truths of evolution. Truth. Very few people doubt that things fall. Anyways, I'm off for the day.

It wouldn't be a theory if we were not positive it existed. Truth: A theory is an explanation for a phenomena supported by tests under the scientific method.

It isn't something we think exists. It's something were sure enough exists that we claim it as the explanation.

RotationSlimWang
08-11-2007, 07:35 PM
the·o·ry /ˈθiəri, ˈθɪəri/ Pronunciation Key - Show Spelled Pronunciation[thee-uh-ree, theer-ee] Pronunciation Key - Show IPA Pronunciation
–noun, plural -ries. 1. a coherent group of general propositions used as principles of explanation for a class of phenomena: Einstein's theory of relativity.
2. a proposed explanation whose status is still conjectural, in contrast to well-established propositions that are regarded as reporting matters of actual fact.
3. Mathematics. a body of principles, theorems, or the like, belonging to one subject: number theory.
4. the branch of a science or art that deals with its principles or methods, as distinguished from its practice: music theory.
5. a particular conception or view of something to be done or of the method of doing it; a system of rules or principles.
6. contemplation or speculation.
7. guess or conjecture.

Alchemy
08-11-2007, 11:24 PM
the·o·ry /ˈθiəri, ˈθɪəri/ Pronunciation Key - Show Spelled Pronunciation[thee-uh-ree, theer-ee] Pronunciation Key - Show IPA Pronunciation
–noun, plural -ries. 1. a coherent group of general propositions used as principles of explanation for a class of phenomena: Einstein's theory of relativity.
2. a proposed explanation whose status is still conjectural, in contrast to well-established propositions that are regarded as reporting matters of actual fact.
3. Mathematics. a body of principles, theorems, or the like, belonging to one subject: number theory.
4. the branch of a science or art that deals with its principles or methods, as distinguished from its practice: music theory.
5. a particular conception or view of something to be done or of the method of doing it; a system of rules or principles.
6. contemplation or speculation.
7. guess or conjecture.

Science uses that first one, skippy. Hence the example following it.

TomAz
08-11-2007, 11:27 PM
theoretical physics uses #7 and freely admits it.

Alchemy
08-12-2007, 08:39 AM
metaphysics uses that one a lot too.

RotationSlimWang
08-12-2007, 01:27 PM
Note the example they used, Alchemy: Einstein's Theory of Relativity. In no way proven true. THEORY.

anti-square
08-12-2007, 01:31 PM
According to M-theory, "gravitons" is the fuel that supports gravity, but we can't measure it let alone see it, to prove its existence. It seems to be a hard theory to grasp since they talk about six other additional dimensions.

mountmccabe
08-12-2007, 01:48 PM
Note the example they used, Alchemy: Einstein's Theory of Relativity. In no way proven true. THEORY.

Theories don't get proven true.

Theories such as special relativity give us equations and ways of looking at things. If these equations fit with the data and, even better, generate predictions about things that'll happen and they end up happening then that lends more and more credence to the idea that the theory is a good one.

We're guessing at the code for the universe; there's no way to say this is exactly how it happens because we can't see all possible conditions.

miscorrections
08-12-2007, 01:50 PM
sometimes i think about the possibility that everything we think we know about science is utterly wrong.

and then i get alarmed because that would be bad, bad news for my future.

mountmccabe
08-12-2007, 02:00 PM
Engineering and technology say that everything isn't wrong. We can do a lot of things; that means we at least have an idea what we're talking about.

That being said I'm sure plenty of things that seem reasonable now will be laughed at in the future.

It won't be as bad as what seemed reasonable before empiricism took over, or what seemed reasonable after the scientific method took hold but I'm sure errors have been made.

That's why we keep looking, keep testing, keep thinking.

TomAz
08-12-2007, 02:07 PM
the weird thing about gravity is that it appears to be instantaneous. matter and energy can travel no faster than the speed of light, but that rule doesn't apply to gravity. that should be impossible. weird.

because of this logical contradiction, I believe the only valid conclusion is that gravity doesn't exist.

http://starphoenixbase.com/wp-content/uploads/2006/10/coyote-06.jpg

mountmccabe
08-12-2007, 02:13 PM
the weird thing about gravity is that it appears to be instantaneous. matter and energy can travel no faster than the speed of light, but that rule doesn't apply to gravity. that should be impossible. weird.

because of this logical contradiction, I believe the only valid conclusion is that gravity doesn't exist.

First: matter and energy are the same thing.

Second: Information is not energy and thus can travel at whatever speed it wants.

Third: Hmm, wait, what? I got off track there. What do you mean gravity appears to be instantaneous? Are you trying to measure things with a stop watch?

Also: Here is a (short) article on the subject: Does Gravity Travel at the Speed of Light? (http://math.ucr.edu/home/baez/physics/Relativity/GR/grav_speed.html)

RotationSlimWang
08-12-2007, 02:15 PM
I used to like to fuck with people on hallucinogens by explaining to them that the secret truth of gravity is that all the greatest minds of each generation one day suddenly realized that gravity was all a sham illusion, and upon the epiphany they immediately were released from its grasp and floated off into the stratosphere, never to be heard from again.