Scientists Cite Fastest Case of Human Evolution

Goshin said:

I'm not an expert on this subject so let me see if I can determine exactly what you mean.

When you say the oxygen is the same at higher elevations, I assume you mean it remains 21% of the existing pressure (or amount-of-air-per-given-volume), but the partial-pressure of oxy is lower because the overall pressure of the atmosphere is lower... right?

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Not 21% of the existing pressure, 21% of the content. The air we breathe is 21% oxygen. That percentage does not change at 24,000ft, but the pressure does. So whether you're at sea level or 24,000ft, 21% of the atmosphere is oxygen, but the pressure gradient is vastly different.

Medical science does not yet know why this pressure makes a difference for breathing, given that the oxygen content is the same.

danarhea said:

More here at the link.

Yes, evolution may only be a theory, but the evidence in favor of it is massive. And now, we can actually see evolution in action from recent human history. The only discrepancy here is the number of years that this particular natural selection event took place - Biologists maintain 3,000 years, while archeologist claim it happened in 7,200 years. Nevertheless, we have ironclad proof that this evolution among Tibetans did happen.

And here is the problem that I have with certain people in the "Creationist" camp. They ask for proof of evolution, and time and time again, evidence is provided. Yet, when you ask them for proof that God created humans, they reply "Prove that God didn't create humans", which is the kind of an answer that speaks for itself, and as we all know, not a reply that is based even remotely on logical debate. You don't debate by asking people to prove a negative, especially when the scientific method dictates that evidence through experimentation and observation provides evidence that the theory is correct.

Yes, evolution is still a theory. So is relativity, a theory that is used today to focus an electron microscope. So is the periodic table of the elements, without which chemists would still be in the dark ages. And creationism? Hogwash, obviously, since absolutely no evidence has been provided to date that supports it. Of course, if and when creationists come up with even an iota of hard evidence to support their claims, I am willing to listen. As of now, though, I am still waiting.

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Not that I disagree,... I for the most part accept and embrace the 'theory of evolution.'

But as for these Tibetans,.... how is this proof of evolution and not merely a necessary adaptation?

(recognizing of course that the two are closely intertwined)

Zyphlin said:

Belief that in the end science will explain everything and that everything is explainable through natural law and science is in and of itself faith.

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I for one don't think that science will explain everything, even if our scientific knowledge was built upon for the next million years, but I can see how some people might extrapolate the incredible increase in human knowledge that has occurred over the past few hundred years into the distant future.

Zyphlin said:

One may say "But history shows us many things people attribute to gods to be found to be natural through science". Yes, that is true in many...not all...cases thus far.

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The argument of pointing out the the limits of our knowledge of the natural world and saying something like "See, science doesn't know everything. How do you know God(s) didn't cause that?" has a few problems:

• It puts the person who brings up the argument on the defensive by implying that God doesn't explain the things that science has discovered.
• God is immanent in all things, so God is present even in natural phenomenon. (at least that's what some theists claim)
• The argument diminishes in its effectiveness every time science discovers the answer for something science can't explain.
• A person on the fence about their belief in God runs the risk of perceiving God to be shrinking, or becoming more distant from their life with each new discovery. If, in the future, scientists happen to find that simulating the newly refined estimates of the conditions of the early earth results in the creation of self replicating molecules that then start utilizing the energy in the materials around them, then, in my opinion, that discovery shouldn't have an effect on the strength of a person's belief in God.

Zyphlin said:

At the same time, science itself is not falliable.

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I'm assuming you meant "science is fallible".

Zyphlin said:

There has been numerous scientific theories and even things believed to be scientific facts that have been found later to be false.

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Later found out to be false by science that is. Science is done by human beings, so of course mistakes are made. Science is a method of finding things out about the world that starts out by making tentative assertions which are then subjected to tests to see if they conform to reality. In science, a theory is well supported explanation of many facts and observations. Scientific theories can explain facts, but they never become facts. The theory of evolution is a theory just like the theory of gravity, atomic theory and the germ theory of disease are theories.

Zyphlin said:

What it truly comes down to, at the end of it all, is both sides. Either faith/belief that there is something greater than the natural world of which we can not fully comprehend, or faith/belief that everything and anything within the universe is absolutely provable and absolutely natural with anything beyond that completely out of the realm of possability.

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I can see with my own eyes that many things in the universe can be explained by natural causes. I'm open to being shown a reason to consider the possibility that the supernatural exists, but so far every fact that I am aware of is either better explained by natural phenomenon, or doesn't currently have a explanation at all.

Zyphlin said:

I reject this idiotic notion that somehow one form of belief is better or worse than the other. My only contention would be is that once one belief or the other is somehow found to be wrong...such as the notion that Zeus throws down lightening bolts...that continuing to hold that exact belief after that fact is rather foolish. However, we are no where near a point of answering that unquestionably prove the removal of all that is supernatural, so until such a point that science completely and utterly wins out it still boils down, without question to one thing.

Belief.

Forgive me if I don't care about those arrogant enough to believe their belief is better than others. I'm not a fan of extreme fundamentalists...be they christian, islamic, agnostic, or athiest.

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Do you think that your belief that the Earth is round is better, i.e. more correct, than the belief that the Earth is flat? Of course you do. I don't assert that God doesn't exist, I just don't have a belief that God does exist.

As for the theory of evolution, the evidence for it is so overwhelming that no informed fair minded person can reasonably think natural selection or common descent is false.

Chuz Life said:

Not that I disagree,... I for the most part accept and embrace the 'theory of evolution.'

But as for these Tibetans,.... how is this proof of evolution and not merely a necessary adaptation?

(recognizing of course that the two are closely intertwined)

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What's the difference?

Anarcho-fascist said:

What's the difference?

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Well,.. I maybe should have read the article more closely as I see there is likely a genetic shift associated with this "change",... so I guess my question really comes down to where the line is drawn (if anywahere) between a simple adaptation and a full blown example of evolution?

Subtle changes because one group lives in high altitude and another at sea leven doesn't fill int the 'missing links' for example between many of the creatures we conceivably 'evolved' from.

First: No evolutionary scientist is claiming that humans descended from monkeys. That is a fallacy and simply not true. Humans did share a common ancestor with apes about 5 to 8 million years ago, and that ancestor diverged into two lines, one becoming apes, one human eventually. Sorry, pet peeve.

Chuz, the genetic difference is evidence of part of the process of evolution. If the shift continues far enough and leads to speciation, it would be a complete step in the process of evolution. It seems to me that speciation would be unlikely.

Chuz Life said:

Well,.. I maybe should have read the article more closely as I see there is likely a genetic shift associated with this "change",... so I guess my question really comes down to where the line is drawn (if anywahere) between a simple adaptation and a full blown example of evolution?

Subtle changes because one group lives in high altitude and another at sea leven doesn't fill int the 'missing links' for example between many of the creatures we conceivably 'evolved' from.

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No one is saying that it "fills in" anything. Simple adaptations are examples of evolution.

Redress said:

First: No evolutionary scientist is claiming that humans descended from monkeys. That is a fallacy and simply not true. Humans did share a common ancestor with apes about 5 to 8 million years ago, and that ancestor diverged into two lines, one becoming apes, one human eventually. Sorry, pet peeve.

Chuz, the genetic difference is evidence of part of the process of evolution. If the shift continues far enough and leads to speciation, it would be a complete step in the process of evolution. It seems to me that speciation would be unlikely.

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Seems plausible to me,....

Anarcho-fascist said:

No one is saying that it "fills in" anything. Simple adaptations are examples of evolution.

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As I said,... had I read the article more closely,... I would have worded my first post differently.

I think this unconfirmed study shows natural selection at work and not evolution. They can only speculate, but they cannot prove that these 30 genes they are looking at "evolved" and by random chance gave these people an edge in just 3,000 years.

digsbe said:

I think this unconfirmed study shows natural selection at work and not evolution. They can only speculate, but they cannot prove that these 30 genes they are looking at "evolved" and by random chance gave these people an edge in just 3,000 years.

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Pet peeve # 2: Evolution is not a random process. The genetic variations upon which evolution acts is random, but the selection "process" is not. Since there is a survival benefit to being able to better handle the air pressure there, the selection for genetic material is not random. There is clearly a benefit to these genes, and as such they are more likely to be passed on to the next generation. That is not random.

Redress said:

Pet peeve # 2: Evolution is not a random process. The genetic variations upon which evolution acts is random, but the selection "process" is not. Since there is a survival benefit to being able to better handle the air pressure there, the selection for genetic material is not random. There is clearly a benefit to these genes, and as such they are more likely to be passed on to the next generation. That is not random.

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The bolded part is what I am getting at. Evolution states that through random mutations some genes become "better" and more adapted to the environment. Natural selection acts upon these mutated genes and alters the populations genetic makeup over time. The random part is evolution, the selection part is natural selection. The two are not the same, separating existing populations and placing them in different environments will result in natural selection changing the species without any evolution (in the sense of genetic mutations and deleting/new genetic information added) occurring.

My comment is towards the random process of evolution. It is highly unlikely that in just a few thousand years that 30 or so genes randomly mutated to better adapt these people to living in the mountains.

Chuz Life said:

As I said,... had I read the article more closely,... I would have worded my first post differently.

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I was responding to your second post. rats my response was deleted... oh well.

digsbe said:

The bolded part is what I am getting at. Evolution states that through random mutations some genes become "better" and more adapted to the environment. Natural selection acts upon these mutated genes and alters the populations genetic makeup over time.

My comment is towards the random process of evolution. It is highly unlikely that in just a few thousand years that 30 or so genes randomly mutated to better adapt these people to living in the mountains.

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Evolution acts on a random process, but it is not a random process. This is very much in line with Eldridge and Gould's punctuated equilibrium theory.

Redress said:

Evolution acts on a random process, but it is not a random process. This is very much in line with Eldridge and Gould's punctuated equilibrium theory.

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Evolution is a random process. Randomly are genes mutated, and randomly and highly improbably are they ever beneficial to the organism. Because they are beneficial, natural selection acts upon what happened by random chance. Evolution by itself is random, coupled with natural selection it is guided. I just don't think in 3,000 years that the extremely improbable mutations required to alter 30+ genes to adapt a population to live in the mountains could occur. Natural selection would best support this, in that those who did not already have the genes to survive in the mountains died and did not pass their genes on (or they moved back to the lowlands).

digsbe said:

The bolded part is what I am getting at. Evolution states that through random mutations some genes become "better" and more adapted to the environment. Natural selection acts upon these mutated genes and alters the populations genetic makeup over time. The random part is evolution, the selection part is natural selection. The two are not the same, separating existing populations and placing them in different environments will result in natural selection changing the species without any evolution (in the sense of genetic mutations and deleting/new genetic information added) occurring.

My comment is towards the random process of evolution. It is highly unlikely that in just a few thousand years that 30 or so genes randomly mutated to better adapt these people to living in the mountains.

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You yourself have about 100 mutations that your parents didn't have. Do you really mean to say that there couldn't have been one beneficial mutation approximately every hundred years.

digsbe said:

Evolution is a random process. Randomly are genes mutated, and randomly and highly improbably are they ever beneficial to the organism. Because they are beneficial, natural selection acts upon what happened by random chance. Evolution by itself is random, coupled with natural selection it is guided. I just don't think in 3,000 years that the extremely improbable mutations required to alter 30+ genes to adapt a population to live in the mountains could occur. Natural selection would best support this, in that those who did not already have the genes to survive in the mountains died and did not pass their genes on (or they moved back to the lowlands).

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Mutation + Natural Selection = Evolution

digsbe said:

Evolution is a random process. Randomly are genes mutated, and randomly and highly improbably are they ever beneficial to the organism. Because they are beneficial, natural selection acts upon what happened by random chance. Evolution by itself is random, coupled with natural selection it is guided. I just don't think in 3,000 years that the extremely improbable mutations required to alter 30+ genes to adapt a population to live in the mountains could occur. Natural selection would best support this, in that those who did not already have the genes to survive in the mountains died and did not pass their genes on (or they moved back to the lowlands).

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Five Major Misconceptions about Evolution

There is probably no other statement which is a better indication that the arguer doesn't understand evolution. Chance certainly plays a large part in evolution, but this argument completely ignores the fundamental role of natural selection, and selection is the very opposite of chance. Chance, in the form of mutations, provides genetic variation, which is the raw material that natural selection has to work with. From there, natural selection sorts out certain variations. Those variations which give greater reproductive success to their possessors (and chance ensures that such beneficial mutations will be inevitable) are retained, and less successful variations are weeded out. When the environment changes, or when organisms move to a different environment, different variations are selected, leading eventually to different species. Harmful mutations usually die out quickly, so they don't interfere with the process of beneficial mutations accumulating.

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Anarcho-fascist said:

You yourself have about 100 mutations that your parents didn't have. Do you really mean to say that there couldn't have been one beneficial mutation approximately every hundred years.

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And the vast majority occur on introns that code for nothing. Most mutations that significantly altered a gene would result in death of the developing fetus or some genetic disease. Out of the billions of base pairs in one's DNA, the mutation has to happen at the right spot for over 30 genes in individuals in just 300 years. Plus, what kind of mutations are these? Simple point mutations? Any kind of beneficial mutation would have to alter the function of the protein to where it becomes more efficient, which most likely would require several mutations and changes in each of the 30 genes being looked at.

Anarcho-fascist said:

Mutation + Natural Selection = Evolution

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I am focusing on the mutation aspect. You are right in that mutation + natural selection=evolution. I should have more clearly defined that I am focusing on the random mutation aspect to the evolutionary theory and not the distinct and different natural selection part.

Redress said:

Five Major Misconceptions about Evolution
There is probably no other statement which is a better indication that the arguer doesn't understand evolution. Chance certainly plays a large part in evolution, but this argument completely ignores the fundamental role of natural selection, and selection is the very opposite of chance. Chance, in the form of mutations, provides genetic variation, which is the raw material that natural selection has to work with. From there, natural selection sorts out certain variations. Those variations which give greater reproductive success to their possessors (and chance ensures that such beneficial mutations will be inevitable) are retained, and less successful variations are weeded out. When the environment changes, or when organisms move to a different environment, different variations are selected, leading eventually to different species. Harmful mutations usually die out quickly, so they don't interfere with the process of beneficial mutations accumulating.

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I am not ignoring the natural selection aspect. I am merely focusing on the chance aspect and stating it is borderline impossible for the right random chances required for natural selection to take effect upon them to happen in just 3000 years.

digsbe said:

I am not ignoring the natural selection aspect. I am merely focusing on the chance aspect and stating it is borderline impossible for the right random chances required for natural selection to take effect upon them to happen in just 3000 years.

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And you are basing this statement on what?

Redress said:

And you are basing this statement on what?

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I think he is referring to the scarcity of beneficial mutations, and the improbability that that particular combination would actually come up to BE selected and conserved in a mere 3,000 years among a relatively small population.

We see mutations all the time. In the vast majority of cases, they kill the mutated fetus, or are a survival-negative or survival-neutral, like calves born with an extra set of useless legs.

For something so singularly appropriate and useful to turn up (by random chance) to be conserved/selected in 3,000 years in a smallish population seems very unlikely. Digsbe's hypothesis that those who already had the genes survived to reproduce and those who didn't didn't, seems much more probable.

Goshin said:

I think he is referring to the scarcity of beneficial mutations, and the improbability that that particular combination would actually come up to BE selected and conserved in a mere 3,000 years among a relatively small population.

We see mutations all the time. In the vast majority of cases, they kill the mutated fetus, or are a survival-negative or survival-neutral, like calves born with an extra set of useless legs.

For something so singularly appropriate and useful to turn up (by random chance) to be conserved/selected in 3,000 years in a smallish population seems very unlikely. Digsbe's hypothesis that those who already had the genes survived to reproduce and those who didn't didn't, seems much more probable.

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If you read the article, there is this:

The Beijing team analyzed the 3 percent of the human genome in which known genes lie in 50 Tibetans from two villages at an altitude of 14,000 feet and in 40 Han Chinese from Beijing, which is 160 feet above sea level. Many genes exist in a population in alternative versions. The biologists found about 30 genes in which a version rare among the Han had become common among the Tibetans. The most striking instance was a version of a gene possessed by 9 percent of Han but 87 percent of Tibetans.

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The genes where already in the population as a survival neutral gene, and for those living at the high altitude, it was heavily selected for(3 times the infant mortality for those without compared to those with at that altitude).

Redress said:

If you read the article, there is this:



The genes where already in the population as a survival neutral gene, and for those living at the high altitude, it was heavily selected for(3 times the infant mortality for those without compared to those with at that altitude).

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So if the gene was already present in the "control population" (han), then it seems likely that digsbe's point, that it wasn't a mutation in the Tibetan population but rather the survival of those who HAD the gene sequence that resulted in the current situation. An adaptation through conservation of an existing gene-set in survivors, rather than a "new" set of genes produced by mutation.

It might seem like a fine point, but when arguing the difference between "microevolution" (expression of existing genes for environmental adaptation) and "macroevolution" (series of selected mutations producting NEW genes, eventually changes a tree-lizard into a bird) it is a significant point. :shrug:

Examples of microevolution taking place around us abound: how birds of the same species have different shaped beaks on this island than on that island, due to the type of food supply, is a way that existing genes are expressed differently based on the environment. "Macroevolution", where NEW genes come into existence via mutation and result in an offspring that has a radical and obvious genetic difference from the parent species... to my knowlege we have yet to observe an recordable event that can be thus labeled with indisputeable evidence, outside of assumptions based on the fossil record.

It is as Goshin says, evolution requires random chance in order to go to the next step of natural selection. The fact that these genes already existed though proves that nothing has been "evolved" or altered genetically. It's as simply as this. Those who already had the genes that better suited them to live at high altitude were the ones that survived and passed on that gene to their kids. Those without those genes either died or moved back to lower altitudes. This is a case of natural selection, not evolution. Regardless, the 3,000 years would be insufficient time according to evolutionary scales for these 30 genes to change into something beneficial through random mutations.

Goshin said:

So if the gene was already present in the "control population" (han), then it seems likely that digsbe's point, that it wasn't a mutation in the Tibetan population but rather the survival of those who HAD the gene sequence that resulted in the current situation. An adaptation through conservation of an existing gene-set in survivors, rather than a "new" set of genes produced by mutation.

It might seem like a fine point, but when arguing the difference between "microevolution" (expression of existing genes for environmental adaptation) and "macroevolution" (series of selected mutations producting NEW genes, eventually changes a tree-lizard into a bird) it is a significant point. :shrug:

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You missed the "survival neutral gene" part. Just as not all mutations are helpful, neither are they always harmful. Some genes get passed down often because it's not particularly necessary that they don't.

However, once those neutral traits are actually proved necessary to survival, only those who possess them live long enough to reproduce and those traits are expressed with near perfect consistency. That's how natural selection works.

While technically a tree-lizard can evolve into something that flies, your statement gives me the feeling that you don't understand that many, many millions of years go into speciation. I could be wrong (about you not getting this point), it's just that it sounded a little too similar to the oft-given "have you ever seen a cat turn into a dog?" creationist rebuttal.