evangelicals trying to hide hominid fossils

Ahnimus

I find it kind of ironic that I was criticized for not making my own statements, but rather quoting facts. In the end, I have to quote facts to get my point across.

Ahnimus

angelica wrote:

Since you seem to gloss over the facts, Ahnimus, with smokescreening, name calling, and degradation I wanted to present them in a straight-up manner. Maybe you will get my point. I'm guessing you'll gloss over it, though, and I can live with that.

In the end: If I am held at gunpoint, and I observe and experience being held at gunpoint, this is empirical knowledge. "The term "empiricism" has a dual etymology. It comes from the Greek word εμπειρισμός, the Latin translation of which is experientia, from which we derive the word experience." --wikipedia.

I find it kind of ironic that if I make a false statement the board jumps all over me. But since you've repeated this false statement countless times, only one or two people have challenged you. It may be some kind of indication then that no one besides you has challenged me on this.

Ahnimus

Scubascott wrote:

Maybe the reputation of black guys is just unfounded?

I think that to be the case.

Although, I would argue that black people have better DNA statistically speaking. With the exception of sickle-cell anemia and a few others.

Scubascott

Ahnimus wrote:

I think that to be the case.

Although, I would argue that black people have better DNA statistically speaking. With the exception of sickle-cell anemia and a few others.

Better? For what?

And sickle-cell anaemia has its advantages too. Malaria resistance.

Ahnimus

Scubascott wrote:

Better? For what?

And sickle-cell anaemia has its advantages too. Malaria resistance.

Well, yea, malaria resistance is the basis of the evolutionary change. Which is good in some places.

Ok, I apologize for quoting a textbook, I couldn't remember everything

Cystic fibrosis (CF)
1 in 2,500 Caucasian births; 1 in 15,000 African-American births.

Phenylketonuria (PKU)
1 in 10,000 Caucasian births; rare in children of African or Asian ancestry

Tay-Sachs disease
1 in 3,600 births to Jews of European descent and French Canadians

(Kuller, Cheschier, & Cefalo, 1996; Strachan & Read, 1996)

That's all

gue_barium

Ahnimus wrote:

Well, yea, malaria resistance is the basis of the evolutionary change.

That is called Adaptation. Adaptation and Evolution, though related and sometimes interdependent, are not the same thing.

Ahnimus

gue_barium wrote:

That is called Adaptation. Adaptation and Evolution, though related and sometimes interdependent, are not the same thing.

Are you suggesting that sickle-cell anemia is the result of adaptation and not evolution?

gue_barium

Ahnimus wrote:

Are you suggesting that sickle-cell anemia is the result of adaptation and not evolution?

It's quite possible that it is neither.

Ahnimus

gue_barium wrote:

It's quite possible that it is neither.

I suppose, but it is a hereditary trait, wouldn't that imply evolution?

gue_barium

Ahnimus wrote:

I suppose, but it is a hereditary trait, wouldn't that imply evolution?

It could. Both Evolution or Adaptation. For sure.

Environment plays a role, too. And when I say "environment" I mean the full spectrum.

Ahnimus

gue_barium wrote:

It could. Both Evolution or Adaptation. For sure.

Environment plays a role, too. And when I say "environment" I mean the full spectrum.

Ok, I see. Hey, maybe they get sickle-cell anemia out of free-will.

gue_barium

Ahnimus wrote:

Ok, I see. Hey, maybe they get sickle-cell anemia out of free-will.

Those damn hippies.

Scubascott

Hey Ahnimus and Gue,

I was just reading the discussion you guys were having about adaptations vs evolutionary changes. Its really just semantics, but maybe I can help.

The term adaptation refers to a trait that has been developed over time due to selective pressure. It allows the organism to perform some function specific to its environment or lifestyle. In other words adaptations (in the biological sense of the word) come about through evolutionary change.

The sickle-cell anaemia mutation is an example of a genetic trait that can be selected for by an external selective pressure (malaria). In low-altitude regions of the tropics, the mutation is advantageous, because it confers a resistance to malaria. It could therefore be considered an adaptation to a tropical climate where malaria is present, but its really just a single mutation, which has negative side effects. There isn't a cumulative effect of multiple rounds of selection over many generations on the change, the trait is either expressed or not expressed, so rather than 'adapting' over time the trait has just become more common amongst the general population, so the term adaptation isn't really appropriate.

BTW, Unless I'm mistaken (it has been known to happen once or twice before) sickle-cell anaemia occurs in all races. The mutation is just more common amongst people of African decent because it has been selected for in that region.

Ahnimus

Scubascott wrote:

BTW, Unless I'm mistaken (it has been known to happen once or twice before) sickle-cell anaemia occurs in all races. The mutation is just more common amongst people of African decent because it has been selected for in that region.

I guess, eh. I didn't mean it that exclusively. I mean, if a black dude with the gene impregnates a caucasian woman, then it's bound to happen eventually.

I may have taken that sound byte too literally.

Scubascott

Ahnimus wrote:

I guess, eh. I didn't mean it that exclusively. I mean, if a black dude with the gene impregnates a caucasian woman, then it's bound to happen eventually.

I may have taken that sound byte too literally.

The mutation can occur spontaneously in any race. It doesn't necessarily have to orignate from an african person.

And I should correct my earlier post. I just checked and it seems that its not simply a case of the trait being either expressed or not expressed. The sickle-cell allele is co-dominant. This means that if you have two copies of the mutation (one on each chromosome) you will get the anaemia, and probably die. But, if you have just one copy, the anaemia only develops at low oxygen concentrations (high altitudes), and you get the benefit of malaria resistance.

gue_barium

Scubascott wrote:

The mutation can occur spontaneously in any race. It doesn't necessarily have to orignate from an african person.

And I should correct my earlier post. I just checked and it seems that its not simply a case of the trait being either expressed or not expressed. The sickle-cell allele is co-dominant. This means that if you have two copies of the mutation (one on each chromosome) you will get the anaemia, and probably die. But, if you have just one copy, the anaemia only develops at low oxygen concentrations (high altitudes), and you get the benefit of malaria resistance.

That kicked my ass. LMFAO

Ahnimus

Scubascott wrote:

The mutation can occur spontaneously in any race. It doesn't necessarily have to orignate from an african person.

And I should correct my earlier post. I just checked and it seems that its not simply a case of the trait being either expressed or not expressed. The sickle-cell allele is co-dominant. This means that if you have two copies of the mutation (one on each chromosome) you will get the anaemia, and probably die. But, if you have just one copy, the anaemia only develops at low oxygen concentrations (high altitudes), and you get the benefit of malaria resistance.

Are there still disadvantages to having single-allele anemia?

Or would that be considered a positive change?

gue_barium

gue_barium wrote:

That kicked my ass. LMFAO

Not sure why.

gue_barium

Scubascott wrote:

Hey Ahnimus and Gue,

I was just reading the discussion you guys were having about adaptations vs evolutionary changes. Its really just semantics, but maybe I can help.

The term adaptation refers to a trait that has been developed over time due to selective pressure. It allows the organism to perform some function specific to its environment or lifestyle. In other words adaptations (in the biological sense of the word) come about through evolutionary change.

The sickle-cell anaemia mutation is an example of a genetic trait that can be selected for by an external selective pressure (malaria). In low-altitude regions of the tropics, the mutation is advantageous, because it confers a resistance to malaria. It could therefore be considered an adaptation to a tropical climate where malaria is present, but its really just a single mutation, which has negative side effects. There isn't a cumulative effect of multiple rounds of selection over many generations on the change, the trait is either expressed or not expressed, so rather than 'adapting' over time the trait has just become more common amongst the general population, so the term adaptation isn't really appropriate.

BTW, Unless I'm mistaken (it has been known to happen once or twice before) sickle-cell anaemia occurs in all races. The mutation is just more common amongst people of African decent because it has been selected for in that region.

Thanks for the info. I can't use it, but thanks anyway.

Scubascott

Ahnimus wrote:

Are there still disadvantages to having single-allele anemia?

Or would that be considered a positive change?

Yes. . . .That's what I'm saying.

You can have two copies of any particular gene. Sometimes there are different versions of the same gene. These are called alleles. In the context of sickle-cell anaemia, there are two possible alleles, the normal one, and the mutation.

If you have two copies of the normal allele, you have normal haemoglobin and normal blood cells. If you have one normal copy, and one mutated copy, you produce both normal haemoglobin, and the mutated form. You can still survive, because you enough of the normal haemoglobin to carry oxygen in your blood, but at high altitude, the effect of the abnormal haemoglobin is manifested as anaemia, and you die (or get pretty sick at least). If you have two copies of the mutant allele, and no normal copy, you're pretty well fucked. You don't have any normal haemoglobin to carry oxygen, so you die.

The advantage of having one copy of each allele (the normal one and the mutant one) is that you get more resistance to malaria (not sure about the mechanism of this). The disadvantage is that you can't go to high altitudes. So its only a positive change if you live near sea level, in the tropics. Otherwise it kinda sucks.