Posted on 12/09/2003 7:47:21 AM PST by PatrickHenry
Was speciation observed?Yes!
I don't have a Science subscription so I don't know what the original study says, but from what the press release says I can't see where this is such a big deal.
The scientists used a new technique to knock out one gene from fruit flies and then replace it with one of two slightly different versions of the same gene.
They focused on a gene called desaturase2 that plays a role in fat metabolism. Flies from Africa and the Caribbean, where there is tremendous competition for food but cold temperatures are not a problem, have one version of ds2. Flies from cooler climates, where there is less competition for food but greater temperature variation, have a smaller, inactive version of ds2.
The same gene plays a role in the production of cuticular hydrocarbons -- waxy, aromatic compounds that coat the abdomen of female flies. A male fly, in a romantic mood, strokes the female's abdomen with his feet, which have sensors that recognize specific hydrocarbons, like a perfume.
In a previous report, Wu's laboratory found most males with the temperate version of the ds2 gene preferred females with the same gene; tropical males preferred tropical females.
So, what did they discover that's new here? They already knew that the African & Caribbean flies had two variants of ds2. Apparently they already knew that ds2 has a role in both fat metabolism and pheromones. It sounds like they gave some African flies the Caribbean version of ds2 (or vice versa), then they observed different mating preferences between the two types.
But they could've just taken some African flies & some Caribbean flies & observed the same behavior. Or is the new discovery the fact that it was the differences in the ds2 gene alone that causes this behavior, as opposed to all the other genes that make Africans different from Caribbeans?
BTW, do they say how much of a mating preference there is between Africans & Caribbeans? And how much between the ds2 mutants they made?
Basically, that pheromone related genes, which account for much of the sexual isolation in flies, are involved in ecological adaptation. In this case, one gene is involved in both mating isolation and adaptation to temperature and starvation. There was some indication of mating isolation, but not enough to determine that this gene is solely responsible for complete mating isolation. As we know, such an isolation is never absolute.
They certainly procreate among each other. The question is whether they procreate with the non-altered species. What they say in the article is that there was a positive correlation between isolating mating behavior and the different alleles used. In other words, they still mated, but less so. When that is combined with adaptation to different environments, mating might be less.
We already know that closely related species in the same environment, like Darwin's finches, do mate but at reduced frequency.
They certainly procreate among each other. The question is whether they procreate with the non-altered species. What they say in the article is that there was a positive correlation between isolating mating behavior and the different alleles used. In other words, they still mated, but less so. When that is combined with adaptation to different environments, mating might be less.
The existence of a gene that both creates pheromones (or influences its scent), and makes it possible for the fly to thrive in a different environment, is very interesting. In this case the single gene mutation would amplify its pressure towards speciation in the founder population that finds itself in the new environment.
I'm just wondering what this experiment did, exactly. IOW, what made this particular experiment worthy of being called "the perfect experiment".
Myself, I'm more impressed by the yeast experiment, where they took two similar species of yeast, and reversed a stretch of one species' chromosome to match the arrangement in the other, and found that they could mate & produce 30% fertile offspring (up from 1%). This showed that a single mutation can go a significant way towards speciation.
Apparently you take issue with my question about wherther this experiment is more supportive of intelligent design theory thatn evolutionary theory. But you don't seem to address the question, just take issue with it. So, if you take issue with the idea of it being more supportive of intelligent design than evolution, I have to assume you believe it to either be more supportive of evolution or equally supportive of both or irrelevant to either one. Or you think it actually proves one of those positions (which neither the authors nor I seem to think)
Could you say which is your position and why?
There is no Intelligent Design Theory. Why? There is no need.
Well, it does seem to get discussed quite a bit.
Oh, thanks for coming through on one of my predicted responses. Yours is #2 on my list.
I don't know a person on the planet with an IQ over 90 who can't make false statements and then predict responses. I think I'll go back to lurking thank you very much.
Good stuff. Keep 'em coming!
- It's a designed experiment. That proves ID!
- It's a lie!
- It hasn't speciated yet!
- Blasphemy!
- They're interpreting it through their naturalistic materialistic worldview.
- How dare you use the screen name "PatrickHenry"?
- Yeah, but "get your own dirt!"
- This is only micro evolution, not macro evolution
- They said: "... may also be on their way to sexual isolation ..." so it's typical evo weasel wording!
- Playing god is what they are doing.
- The point is this was done MANUALLY, It was NOT observed naturally ...
- ... we as a people aren't all that bright. How much tweaking does it to take to do serious damage.
- A deliberate laboratory forced change does NOT equal natural change.
- Speciation my butt.
- Now I admit, this is interesting even exciting, but proof? speciation?
- So desperarate for REAL evidence of speciation, they will unashamedly boast of this?
- Gee, a fly got turned into. . . a fly! Imagine that!
- Does the article say if the differentiating species can still interbreed?
- But will the "new species" be able to procreate?
- [Y]ou aren't nearly as intelligent as your reply here indicates you believe yourself to be.
I agree. This was more a demonstration of intelligent design because this gene changing was done via intelligent design not Darwinist mutation and natural selection. If "scientists" create a 1968 Ford Mustang in the lab, does that mean a 1968 Ford Mustang could be created in the "wild" via Darwinist mutation and natural selection?
1. Source.
2. Evolution or Creation
3. The Origin of Life
4. Is Man a Machine?
5. Environment or Genetics
6. Is Biogenesis Scientific?
7. Dimension Theory/Time Theory
PatrickHenry, unable to intellectually respond to any of the responses, is force to merely list them.
:-)
Nope. And not a word about Reggae either...
That is sooo amusing, Patrick -- it's the Darwinists who are in denial. So did God or mutation change the gene or was the change a product of intelligent design by some lab maven?
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