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Author Topic:   Dogs will be Dogs will be ???
Coragyps
Member (Idle past 849 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 185 of 331 (475505)
07-16-2008 12:08 PM
Reply to: Message 173 by AlphaOmegakid
07-15-2008 2:08 PM


Re: How many micros equal a macro?
In every documented case of a "beneficial" mutation the genetic capacity for the benefit is existant in the population.
Every case? Baloney.
A sizeable fraction of West Africans in Burkina Faso have a mutation in the gene that makes hemoglobin. It changes the same amino acid that the sickle-cell anemia mutation does, but the change is to a third, different form of hemoglobin called hemoglobin C. Kids that are homozygous for this variant get clinical malaria 7% as much as their classmates with boring old "normal" hemoglobin A. Most people with hemoglobin C never know it because they never have ill effects from it. But they survive malaria....
The mutation "exists in the population," alright. But all indications are that it's only existed there for a thousand years or so. The frequency of the gene in (non-removed by migration and slave-trade) populations maps to make a bull's-eye centered in the homeland of the Mossi people. It's beneficial in a malarious environment like that one. It's documented. You are mistaken.

"The wretched world lies now under the tyranny of foolishness; things are believed by Christians of such absurdity as no one ever could aforetime induce the heathen to believe." - Agobard of Lyons, ca. 830 AD

This message is a reply to:
 Message 173 by AlphaOmegakid, posted 07-15-2008 2:08 PM AlphaOmegakid has not replied

  
Coragyps
Member (Idle past 849 days)
Posts: 5553
From: Snyder, Texas, USA
Joined: 11-12-2002


Message 209 of 331 (476135)
07-21-2008 12:31 PM
Reply to: Message 204 by AlphaOmegakid
07-21-2008 10:14 AM


Re: Can you see my hands waiving?
Please note that the "easy" challenge was to show mutations identified as being "beneficial" and "morphological".
I refer you again, AOK, to post 185 of this thread. At least a part of the reason that people with hemoglobin C don't suffer symptoms of malaria, even when infected with Plasmodium parasites, is a matter of morphology. If you have Plasmodium in your red blood cells and have hemoglobin A, the blood cells grow "knobs" and get "sticky" - they gum up in capillaries and cause blockages in your circulation that can kill you. If you have hemoglobin C, you get very few "knobs" and don't get blockages. So you have a better chance to live past infancy and have kids that do, too.
Morphology. Beneficial.
Nature, v435, pp1117-1121, (2005)
.....countdown begins to "well, that's not really morphological, 'cause it's not a femur or a skull..."
Edited by Coragyps, : typo

"The wretched world lies now under the tyranny of foolishness; things are believed by Christians of such absurdity as no one ever could aforetime induce the heathen to believe." - Agobard of Lyons, ca. 830 AD

This message is a reply to:
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Replies to this message:
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