Posted on 02/08/2002 5:40:18 AM PST by JediGirl
Scientists have discovered the first genetic evidence explaining how small mutations can cause big changes in an organism's body.
Until now there has been little proof that one genetic change can successfully lead to a whole new species.
A University of California study has shown how a mutation in a 'master gene' which controls others could lead to a major body change.
The study looked at a class of genes known as Hox, which switch on and off other genes during an organism's development as an embryo.
The San Diego team used brine shrimp to prove a simple mutation here suppressed 15% of the limb development in the animal's central body region.
This would have allowed its ancestors, which had limbs on every segment of its body to lose their hind legs and evolve into six-legged insects.
Professor William McGinnis, who led the study, claims it answers the question as to how evolution can introduce big changes into an animal's body shape and still generate a living animal.
He said: "Creationists have argued that any big jump would result in a dead animal that wouldn't be able to perpetuate itself.
"And until now, no one's been able to demonstrate how you could do that at the genetic level with specific instructions in the genome."
Story filed: 12:41 Friday 8th February 2002
This is just a sample of what's to come, some day. You are no doubt familiar with the constant creationist chant: "If you guys could just create life in the lab, then you might be able to convince me that you're onto something." (And of course they always say this with fingers crossed, hoping the deed will never be accomplished, as their whole fragile worldview hangs on the notion that it's an impossible thing to do.)
But now we see the fallback position: "Oh yeah? Well, doing it in the lab only proves ID, and it's no proof that it happened like that in nature." The game never ends.
I think I am going to have to insist on a higher standard of proof than, "If we can imagine how it might of happened then you must accept that it DID happen." The imagination often leaves out many obstacles, as any Star Trek episode will demonstrate!
Like yourself, I wonder if the claim is true that no mosquito had the gene prior to 1984. IF true, that is HUGE. You evos should be all over that. What is much, much, more likely is that very few or no mosquitos had been tested for that gene prior to 1984. It was in the population, sort of like genes for red hair in human population. It had not been discoverd, but it was present.
That's my story, and I'm sticking to it, unless you folks can show otherwise to the same standard of evidence that is required of cold fusion or any other kind of science except evolution.
Au contraire my toothy friend. Training wheels are pretty useless unless one has the whole bike to begin with! Did the first cell have the 'whole bike' (code potential for every gene of every creature that has ever lived on Earth) in its DNA? If so, I find it astonishing beyond any belief that such a cell was the result of chance alone.
So do I. Random isn't the only option.
The point is, the earliest leg-like structures were probably something like cilia. Brine shrimp limbs function in that way.
But bigger stronger legs can have their advantages... if there are fewer of them. I don't deny the need for new information and new code, I'm just saying that getting rid of the genetic cobwebs is useful too.
I am not talking about the fossil record specifically, but here alive today. Most (if not all) of the forms found in fossils can be found in some altered state today, most of the forms (if not all) today can be found as fossils. Remember we are not talking about forms that died off due to natural selection, remember, we are talking about forms that had increased survivability over their precurssors.
I can use a software program to morph a picture of my daughter into a picture of a ladybug, and produce pictures of all the intermediate steps but demonstrating that in the lab is not reality, is it.
This is where I fall off the Evo train. There is a sort of beautiful poetry to imaging that God created this one self running mechanism and set it loose to produce the results today, but there is just too much evidence that he punctuated the mechanism with interventions along the way to ignore. IMHO
v.
I'll give it a try. Not that I don't give credence to the gradient concept you mentioned in your ealier post to me. I do, but it still says nothing about how all of the new genes that the gradient works with came about. In addition, the idea that the first cell came up with a gradient that just happened to have the potential to unfold itself into all of Earth's biota goes way above my credulity threshold. I am sure you feel the same way. What is left, Theistic evolution of some kind?
But I digress. The 17 gene changes that result in major morphological changes had about 543 million years to occur. Plenty of time for 17 changes. Except those are not the only changes needed to make a brine shrimp into a fly. Numerous other changes had to occur at various other stages of that process each one producing a viable organism superior to everything else around at some niche.
If ANY of those 17 changes produce deadly or even very deliterious changes, the whole process is impossible regardless of the time allowed. And they must occur in conjuntion with many other changes.
I don't think it is accurate to imply that only 17 changes were needed. That is only for this one little area. Nor do I think it is safe to assume that shrimp-to- flys made the transition in only 17 jumps. Do you? I would guess hundreds of thousands of intermediate organisms. That means there must be a large number of 'islands or viablility' in those gene combinations between those 17 examples. Simply put, no one has demonstrated that to be the case.
This is not evolution. Evolution rejects the idea of pre-determination and master genes. Funny how they take anti-evolution stances and label them pro-evolution.
Watch them goalposts move yet again. How long is the field now - about 300 yards?
I suspect that if today's geneticists and molecular biologists can accomplish such technical wonders as gene splicing and cloning, that the much greater intelligence of Satan could potentially have done it too. The inner workings of the DNA molecule would not have been hidden from the prying eyes of Satan and his henchmen. If today animal genes can be inserted into human DNA, could not it have been accomplished by malevolent spiritual beings bent on destruction of the "image of God"?
Obviously we cannot speak with certainty, for the Bible gives little detail. At the very least, Satan's demons could have selected and indwelt certain men and women, and performed selective breeding experiments to produce over the generations a race of giants. (He could have done the same with animals too, and maybe that's where some of the unthinkable features we see in the fossil record come from. This could represent Satan's rage in trying to fully destroy any vestige of God's once "very good" creation.) Could he not have inserted genes and fabricated clones, mocking and ruining God's majestic handiwork? Perhaps this is why God had to send the Flood, eradicating a civilization beyond repair and starting anew with Noah, preserving the true seed of Adam.
Looks like the ICR is pulling out all of the stops on this one. ;-)
We do see them in nature. A number of these intermediate sequences are listed in this figure. Did you bother to look?
Looking forward - a million years from now "man" will have disappeared and will not have left any evidence he was ever here.
No. As a matter of fact, from sequences obtained so far, the critical difference in this body plan change is contained in only 10 amino acids. So, one piece of the puzzle has been demonstrated. Are you saying that other pieces of the puzzle could never be demonstrated similarly? Or that all the changes for each puzzle piece had to happen simultaneously?
For shame nothing. You have no repeatable eents except those which had intelligent directionin them in the first place. It is not I that is talking up a false notion, it is evolution. You admit this was a man-created act, yet you say it MUST have happened inthe past. And the reason it must have happened in th epast is because the THEORY of evolution demands it. That is not science, that is faith.
Do you these people are ever embarrassed at the stuff they write?
The above, btw, sounds like good material for a Chick tract.
That's the first time I ever heard that one!! I know some creationists are drifting away from the ICR because of doctrine, not science, but I never saw anything like that.
The Bible does say that when the Anti-Christ is killed inthe middle of the 7 year tribulation, he will be resurrected by the Pwoer of Satan, made alive again through demonic power, but there is no mention of Satan ever having thispower ever before, and it sure sounds like the ICR thinks he already has some power!! Goodness!!
Sounds reasonable to me. [Fade in: theme from The Twilight Zone.]
To clarify for us the laity what exactly has been demonstrated, is it sufficient to say no little population of legless brine shrimp was produced? Rather what was achieved was a diminished glow in the modified shrimp embryos, or am I reading this incorrectly?
Methods, accession numbers, and additional references
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How do you define evolution?
The blood clotting article was very interesting. Is blood clotting considered a mutation or do hemophiliacs just have a deleterious mutation?
From one of the links:
The mosquito link was interesting and it looks beneficial.
I appreciate the info on mutations. Prior to your posts I had only heard of sickle cell resistance as a mutation and then it was not considered beneficial. As I pointed out, the link states this mutation is still not considered beneficial.
While I have no problem seeing some of the mutations as beneficial, I have yet to understand how the mutation supports evolution. I have no problem with a mutation supporting microevolution. But for me it stops there. Do you consider the mutations to support anything other than microevolution?
The mutation is lactose tolerance. Originally we were all intolerant. Regards.
That is speculation. Lactose is present in all mammalian milk.
Lactose intolerance and the breastfed baby
Lactose is the sugar in all mammalian milks. It is produced in the breast and is independent of the mother's consumption of lactose. It is present in a constant concentration in breastmilk.
Primary (or true) lactose intolerance is an extremely rare genetic condition and is incompatible with normal life without medical intervention.
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