Posted on 03/28/2006 2:37:59 PM PST by Conservative Coulter Fan
I'd rather take my chances with DDT than with sickle cell anemia. Sickle cell anemia kills people and, apparently, that's one of the best examples of a "beneficial mutation" the evolutionists can come up with. Pretty sad when you think about it.
/ignored
/ignored
The author has no knowledge of legitimate science. A mutation is just that, a mutation.
Most times the mutation is meaningless.
Somtimes the mutation decreases survivability.
Somtimes the mutation increases survivability.
However the author's ignorance is demonstrated in his confusing the appearance with the ability to pass it on.
It is all a question of how does the mutation affect the ability to pass the gene to the next generation.
The vast majority of the time a mutation is negative.
In humans there are at over 800 known genetic diseases that decrease survivability and that's not counting the ones that resulted in non-viable eggs, still-bornes or miscarriages.
Meanwhile the only human mutations that have been suggested to me as beneficial mutations are as follows:
Now Danny Boy, you've been around these threads for a long time and you have been told repeatedly that a vast majority of mutations have no effect on the organism whatsoever. Catch up to 20th century science. It won't hurt.
You really should do a little research before you post. From the first Google hit, Sickle Cell Society
Everyone has two copies of the gene for haemoglobin; one from their mother and one from their father. If one of these genes carries the instructions to make sickle haemoglobin (HbS) and the other carries the instructions to make normal haemoglobin (HbA) then the person has Sickle Cell Trait and is a carrier of the sickle haemoglobin gene. This means that this person has enough normal haemoglobin in their red blood cells to keep the cells flexible and they don't have the symptoms of the sickle cell disorders. They do however have to be careful when doing things where there is less oxygen than normal such as scuba diving, activities at high altitude and under general anaesthetics.From Malaria and the Red CellIf both copies of the haemoglobin gene carry instructions to make sickle haemoglobin then this will be the only type of haemoglobin they can make and sickled cells can occur. These people have Sickle Cell Anaemia and can suffer from anaemia and severe pain. These severe attacks are known as Crises.
Sickle trait provides a survival advantage over people with normal hemoglobin in regions where malaria is endemic. Sickle cell trait provides neither absolute protection nor invulnerability to the disease. Rather, people (and particularly children) infected with P. falciparum are more likely to survive the acute illness if they have sickle cell trait. When these people with sickle cell trait procreate, both the gene for normal hemoglobin and that for sickle hemoglobin are transmitted into the next generation.
...supposed to confer some limited immunity...
It confers enough immunity to be selected for.
Plague causes heart disease placemarker.
This is absurd. hemoglobin-S is a recessive gene. If you only have one copy, you are normally asymptomatic. See my previous post.
All of that is sad enough, but there's another sort of a thing which nobody ever talks about. If I'm a monkey, the only sort of mutation which would be of any benefit to me would be something which makes me a better monkey, bigger, stronger, more efficient (goes further on a bannana) etc. The girl monkeys are gonna like that. The first time, however, a monkey starts to develop ANY sort of a mutation wihch leads or tends in any way towards being anything other than a monkey, like horns, poison fangs, wings, or flippers, the girl monkeys are gonna be gone faster than you can blink.
I've been told all kinds of crap on these boards, but that doesn't mean I believe it.
How many mutations result in a non-viable egg? Unless you can answer that, you can't affirmatively say that most mutations are non-consequential.
Even if you are right, the ones that do affect an organism are still overwhelmingly negative compared to positive. They appear to weaken the gene pool over time, not strengthen it.
Agreed if you only have one copy, you don't have sickle cell anemia.
But if you do have both copies, then you have sickle cell anemia. In that case, the normally round red blood cells become sickle shaped. They don't function correctly, and the body works constantly to remove the defective cells. Somehow this results in resistance but not immunity to malaria.
I mispoke when I said "half the blood defective". I don't know what percentage of red blood cells will take on the sickle shape at any given time in any given patient. But it's enough to confer resistance to malaria.
But you **are** resistant to anemia.
In fact, a lot of the commonest genetic diseases are the same sort of thing:
(Source: Diamond's "Guns, Germs, and Steel")
Sickle cell - malaria
Thallasemia - malaria
Tay Sachs - tuberculosis
Cystic fibrosis - cholera
If you're a carrier for one of these, you're much less likely to die of the corresponding disease. If you marry another carrier, 1/4 of your children will have the birth defect, 1/4 will not have the allele at all, and 1/2 will be carriers, and hence, resistant.
Classical natural selection at work.
But you **are** resistant to anemia.
obviously should have been ...resistant to malaria.
Gettin' late...
Anemia or malaria?
"Classical natural selection at work."
If all classical natural selection did was select for deformities and disfunctions that gave some advantage in defeating an illness, you would never advance from one species to another. It de-evolution not evolution and it won't result in higher order creatures only lower order creatures.
But that's exactly the point. What we see of evolution shouldn't create higher order creatures, instead it should slowly result in weaker and weaker species. Because some of the many defects will get passed on and we aren't seeing any positive mutations to offset them.
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