Posted on 10/01/2015 6:16:47 AM PDT by lasereye
On February 24, 1988, evolutionary biologist Richard Lenski began an ingenious ongoing experiment to test and demonstrate evolution. He and his coworkers have nursed thousands of generations of the common gut bacterium Escherichia coli, feeding them broth with limited nutrients. The team watched for decades to see if the germs might evolve a solution to this low-nutrient challenge. After about 31,500 generations, some finally cracked the code and changed. Evolution promoter Richard Dawkins wrote that this was “a beautiful example of evolution in action,” and that “creationists hate it.”1
The Harvard Gazette recently wrote, “Though the bacteria were originally genetically identical, they have evolved.”2 How could anybody doubt statements like this in light of what happened? But two genetic details topple this “beautiful example of evolution.”
Lenski’s team adds an energy molecule called citrate to the bacteria’s broth. All normal E. coli have a protein gate that brings citrate into the cell by trading out another chemical, but only when oxygen is absent. In wild E. coli, molecular switches interact with the gate genes’ promoter region to build more gates when oxygen levels drop. After about 31,500 generations, the germ’s cellular machinery cut out and pasted these genes into another spot on the bacteria’s DNA. The new location already contained an “on” promoter. These new mutants began promoting gate production even with oxygen present. This “evolved” bacterium could now import and use citrate in the presence of oxygen but was “surprisingly weak when it first appeared.”3
What really happened here? A mutation caused a loss of regulation. In the scientists’ special soup, bacteria with this loss grow for a little longer than others that could still regulate their citrate-gate production.
After about 33,000 generations, something dramatic changed. Those mutants’ descendants suddenly grew like gangbusters, consuming more citrate. When researchers first described this development in 2012, they speculated that mutations constructed new and complicated cellular machinery, but others have since revealed that the second change was not nearly that impressive.4
Instead of gaining new features, the bacteria lost regulation over an additional gate protein—one that pumps the sugar succinate into the cell. A mutation damaged its genetic “off” switch. Cells with both mutations now have two unregulated genes, both producing transport gates. One gate imports citrate by trading out a succinate, and the other pumps in more succinate that can then be traded. By these losses of regulation, citrate lands on the menu even with oxygen present, and the bacteria grow faster than previous generations.
Normal E. coli with intact genetic regulators retain the tools to cope with ever-changing conditions. But throw these mutants into any natural environment and they would fade to the back of the pack as they waste energy making so many extra gates.
So, did Lenski’s bacteria evolve? Well, mutations did help them use more citrate, but only by losing healthy regulation. Molecular biologist Michael Behe wrote,
This is evolution by degradation. All of the functional parts of the system were already in place before random mutation began to degrade them. Thus it is of no help to Darwinists, who require a mechanism that will construct new, functional systems.5
We could say that a man who lost both arms “evolved” the ability to wriggle through a small pipe leading to a new food source, but how would he fare among robust peers with arms? It is the same with these “evolved” bacteria. Lenski’s experiment has now surpassed 50,000 E. coli generations. After all those opportunities to prove evolution can construct something new, these germs have merely shown beautiful examples of degradation in action.
References
Ironically, most creationists I know of have no problem with horizontal variations such as the one this experiment generated.
Nifty!
Why is it that every article from the ICR is simply another criticism of evolutionary theory? And usually a small part of it, which is then extrapolated to “the whole theory must be junk”, just like leftists like to point to one crazed gun-owner and then paint every gun-owner as a crazie.
Not once is there ever an article from the ICR offering evidence in support of an alternate theory.
Not once.
Creation?
No that's adaptation. Show me the critter that evolved into a humming bird or a mouse and then I'll think about it.
Apparently, all ICR does is parrot the work of real scientists, while putting their slant on the work.
I’m starting to think they may have an agenda.
The name Creation Research is an indication of an alternative therom.
30,000+ generations? Gees.... it ought to be a catfish by now.
LOL! Good analogy!
What I find most curious is their tactic of using what they claim doesn't exist (evolution) and club their opponents over the head with it.
It comes down to the source of the information and ability to change.
Is it built into the critter (creation)
or is it “added” by mutation (evolution).
Which is more likely to produce the results we see?
You cut down a forest one tree at a time.
There are scientists out there examining the evidence for a Creator:
http://www.signatureinthecell.com
So, after 33,000 generations, e. coli is still e. coli.
Not once is there ever an article from the ICR offering evidence in support of an alternate theory.
The alternate theory is obvious to me and is even in the name of the ICR, Institute for Creation Research, Creation is the original theory and fact to many of us.
What I mean is that the ICR seems to think there’s only two theories out there, so if they can criticize Evolution enough, then “Creationism” automatically wins by default, no need to supply any proof. That’s not the way Science works - let’s see your proof before we believe.
Besides, the evidence for Evolution is vast and complex, so nitpicking about little points does nothing to invalidate the overall concept.
The Bible is a beautiful and powerful book, but it was never intended as a guide to the geological or biological history of the earth, nor should it be.
Just saying.
That depends on the environment. If the environment has changed so that the only source of food is at the other end of one of those pipes, the man without arms can survive while his "robust" peers are going to starve to death.
I see no evidence of evolution in nature. However, I’ve seen loads of evidence of extinction.
No evidence for evolution at all. Adaptation? Yep, lots of it. Evolution? Not so much.
The Bible has everything we need to know for us to know God and live. Granted it is not a science book, nor is it intended to be. But Genesis says the Lord created all the animals to reproduce according to their kind. The Lord did NOT make a living cell, telling it to evolve and change and fill the planet with life. Nor did He tell the Lemur that it was the chosen precursor for a being that will have a soul.
I believe, in and on faith, what the Bible says, there is NO part of it that is false. Notice I did not say that it explains everything. That understanding comes later. But in the meantime, it is true and sufficient.
I see no evidence of evolution in nature. However, I’ve seen loads of evidence of extinction.
Very true.
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