Re: Evolving altitude aptitude

Hey Brandon,

Well, it would make sense for either Adam or Eve to have carried this particular gene, although it doesn’t mean that the gene was necessarily active in either one of them. People carry the genes for many different traits which they don’t have themselves.  Even though I have green eyes, I probably carry the genes for blue, brown, and/or other eye colors.   I’ve seen families with red-headed kids who whose closest red-headed relatives were several generations back.  Adam and Eve would have had the genetic material for all the possible traits, and then various populations, as they spread out and became more isolated, would have lost some traits because of less genetic material available to pull from.

I do find it much more logical and scientifically sound to believe that a Creator God created everything than to believe that living organisms came from non-living material, then developed complex genetic information through mutation and natural selection, and without any intelligent guidance.  I suppose this will continue to be a bone of contention for us.  Perhaps you could find research showing how Darwinian evolution handles handedness, entropy, and the other problems I’ve mentioned?  

Also, if I could find one stretch of human DNA that had three beneficial configurations, wouldn't that disprove your logic?  

I’m not sure what you’re trying to say here—perhaps you could rephrase?

Susan

Fwd: Evolving altitude aptitude

Hey Susan,

I absolutely detest having to talk about what you base your ideas on, but I see no way around it in this case. You say that this special stretch of DNA in the Tibetans has always been around, presumably placed there by a god for the precise reason of making a happy population on a mountain  but if you also believe that all of humankind came from one man and one woman, then you believe that either Adam or Eve had this special stretch of DNA that the Tibetans now have. Is that what you really believe?

Also, if I could find one stretch of human DNA that had three beneficial configurations, wouldn't that disprove your logic?

-Brandon

Re: Evolving altitude aptitude

Hey Brandon,

Yep, I’d say that both articles present very good examples of adaptation, not of Darwinian evolution, since in both cases, there was no change in the basic organism—the frogs were still frogs, and the people were still people.  Both the frogs and the humans adapted to their environment by using genetic information already present in a portion of the population.  In both studies, the assumption is that there was a mutation at some point, yet we already know that most mutations are harmful or, at best, almost neutral (or barely harmful).  In neither article is there proof that a mutation actually occurred—it is assumed to have occurred because the scientists were working from an evolutionary perspective.  What is known is that information in DNA allowed the frog and human populations to adapt to their environments—that information kicked in when needed in order for the population to adapt.  

The Berkeley article talked about gene variation frequency of a section of DNA called EPAS1.  Scientists compared the frequency of EPAS1 in the Tibetans and in other Chinese populations, and found that the Tibetans had the highest frequency.  Note that some non-Tibetans also had this gene, although at a much lower frequency—why would this be the case if the gene were a mutation among the Tibetans?  I suppose one might say that the mutation occurred in one or two individuals before humans migrated to Tibet, but then, why would such a mutation spread to the general population when there would be no need to select for it?  If none of the earliest Tibetans had the proper variant of the EPAS1 gene which allowed them to adapt to their environment, they would have had to deal with the altitude sickness that most others experience—why would they have continued to live in such a hostile environment for the ‘hundred or so generations” it took for them to adapt?  The more likely scenario is that the proper variant was already in place (though not necessarily active, because not needed) in a good number of Chinese, and those early Tibetan settlers that had it adapted and fared better.  Over time, as the Tibetans reproduced among themselves, the frequency of the trait increased, while it stayed low elsewhere.

He explained that the faster moving toads even reproduced more quickly. But this could point to a chink in their biological armour.
"They have to be trading something off to do that," he said. "And one of the things we suspect is that they're trading off their immune systems."

It was interesting to note that the researchers expected the ‘good’ mutation leading to faster movement would be accompanied by something negative (suspected lower immunity).  This goes along with what I’ve said before—that most mutations are negative, and when ‘good’ mutations are selected/activated, they will be accompanied by ‘bad’ ones, as selection is by phenotype and not genotype—one cannot select for ‘good’ traits only.  In truth, neither individual organisms nor nature actively selects anything.  Individuals live or die based on individual ability to adapt and on other environmental factors (war, sickness, natural disasters,  getting eaten by another animal, etc.), but they can’t choose which traits to pass on to the next generation.  Individuals with good traits could get eaten or die of sickness before producing offspring, while individuals with maladaptive traits might produce offspring before dying—either way, having a certain trait doesn’t guarantee that it will be passed on.

Susan

Fwd: Evolving altitude aptitude

From: Brandon
Date: Thu, Oct 21, 2010 at 10:29 AM
Subject: Fwd: Evolving altitude aptitude
To: Susan


I've sent u an article about the Tibetans before, but this one is much more in depth. Also, it's an example of an adaptation at the molecular level due to a mutation in DNA that is beneficial to the Tibetans. They even know which stretch of DNA does it. Again, this is natural selection (which naturally involves slight mutations with every generation) / evolution at work.

-b

---------- Forwarded message ----------
From: Ben
Date: Mon, Oct 18, 2010 at 2:54 PM
Subject: Evolving altitude aptitude
To: Brandon


http://evolution.berkeley.edu/evolibrary/news/101001_altitude

Fwd: another evolution article

From: Ben
Date: Tue, Oct 19, 2010 at 10:29 AM
To: Brandon

sorry for the glut of articles lately.  lots of science happening, i guess
http://news.bbc.co.uk/earth/hi/earth_news/newsid_9096000/9096795.stm

----------
From: Brandon
Date: Thu, Oct 21, 2010 at 10:23 AM
To: Susan


I know that you're going to say that it's natural selection and not evolution, but this author clearly doesn't see a distinction between the two (and neither does Dawkins).

-b

Re: How Plants Drove First Animals Onto Land

Hey Brandon,

Well, I suppose that since you’ve returned to our evolution/creation discussion, you must be feeling less stressed.  If that’s true, I’m glad. :)  And hopefully it means that either some stressors have gone away or you’ve found good ways to manage the stress.

Now to the article...  I don’t know what to think, and I’m not sure what you want me to get from it—it appears to me that the researchers took some data about molybdenum and oxygen concentrations, then built a story around it to fit evolutionary ideas.  At least the author first admitted the uncertainty of the models for the distant past before making his assertions about the meaning of the data.

According to another article (http://live.psu.edu/story/38514), researchers at Penn State have found that there was as much atmospheric O2  three and a half billion years ago as there is now, as evidenced by the presence of O2 in the very deepest of rocks sampled—very different from what is claimed in the article you just sent.   See also http://www.nature.com/ngeo/journal/v2/n4/abs/ngeo465.html .  In your article, precursors to plants evolved 400-550 million years ago.  According to the Penn State article, plants or their precursors must have been around 3.5 billion years ago.  If both atmospheric O2 and plants (or their precursors) have been around almost since the beginning, why could not other plants and animals have been around since then, too?  (By the way, the Penn State study stated a conclusion based on what is already known about chemistry and geology.  Your article stated a conclusion, about plants driving first animals onto land, based on evolutionary theory.  Therefore, I think the Penn State study has a higher value.)

The Penn State findings fit well with Biblical creation theory, as it is consistent with the idea that the earth was livable and had plants on it almost from the beginning.  Of course, I disagree with the dating in all the articles, as I’m a young earth proponent and question the millions and billions of years—but that’s for another discussion. :o)

Susan