Here’s an opportunity that is ripe for quote mining and shameless distortion — in the service of The Truth™. We read about it at PhysOrg: Evolution depends on rare chance events, ‘molecular time travel’ experiments show.
Wowie — rare chance events! That’s certain to appeal to the Discoveroids, who are forever claiming that if something functions, yet seems improbable, then it’s obviously overloaded with specified complexity and irreducible complexity (which no one understands except Discoveroids), and therefore, using their “explanatory filter,” they somehow know that it’s powerful and undeniable evidence for the existence and activity of their magical designer — blessed be he!
The preceding paragraph reveals what has happened to your Curmudgeon as a result of blogging in your service. Merely from the title of the PhysOrg article, we can imagine visions of sugar plums dancing in the heads of the Discoveroids. But that was just the title. Lets see what the story is actually about. We’re told, with a bit of bold font added by us for emphasis:
… a team of evolutionary biologists studying ancient proteins has turned speculation into experiment. They resurrected an ancient ancestor of an important human protein as it existed hundreds of millions of years ago and then used biochemical methods to generate and characterize a huge number of alternative histories that could have ensued from that ancient starting point.
Tracing these alternative evolutionary paths, the researchers discovered that the protein – the cellular receptor for the stress hormone cortisol – could not have evolved its modern-day function unless two extremely unlikely mutations happened to evolve first. These “permissive” mutations had no effect on the protein’s function, but without them the protein could not tolerate the later mutations that caused it to evolve its sensitivity to cortisol. In screening thousands of alternative histories, the researchers found no alternative permissive mutations that could have allowed the protein’s modern-day form to evolve. The researchers describe their findings June 16, online in Nature.
Here’s a link to the Nature article: Historical contingency and its biophysical basis in glucocorticoid receptor evolution. But they have another article about Thornton, one of the authors of that paper, that may cause the Discoveroids to hesitate to take him on. That’s here, Prehistoric proteins: Raising the dead, and it says:
Thornton wanted to delve deeper into the puzzle of how complex systems with tightly interacting molecular parts evolve. It was a long-standing conundrum. As Charles Darwin wrote in On the Origin of Species: “If it could be demonstrated that any complex organ existed which could not possibly have been formed by numerous, successive, slight modifications, my theory would absolutely break down.” And what was an evolutionary puzzle to biologists was a target for evolution’s critics. Michael Behe, a biochemist at Lehigh University in Bethlehem, Pennsylvania, and a senior fellow at the Discovery Institute in Seattle, Washington, proposed in the 1990s that such systems — the blood-clotting cascade, for example, or the molecular motor called the flagellum — are so “irreducibly complex” that they could not have evolved step by step, and can only be the product of intelligent design. Thornton says that he didn’t set out to refute intelligent design, but the prospect of a fight hardly put him off. “Been there, enjoyed that,” he says.
The study flipped another finger to intelligent-design proponents — but “I’m sort of bored with them”, Thornton says.
That won’t stop the Discoveroids. If reality itself doesn’t impress them, nothing will. Let’s read on to see what PhysOrg says:
“This very important protein exists only because of a twist of fate,” said study senior author Joe Thornton, PhD, professor of ecology & evolution and human genetics at the University of Chicago. “If our results are general – and we think they probably are – then many of our body’s systems work as they do because of very unlikely chance events that happened in our deep evolutionary past,” he added.
You can see why this is ripe for plucking by the Discoveroids. We continue:
Thornton and others have previously shown that the evolution of modern-day proteins required permissive mutations in the past. But no one had ever investigated whether there were many or few other possible permissive mutations that could have happened, so it remained unknown how unlikely it is that evolution discovered a permissive pathway to the modern function.
Unlikely? If it’s even a little bit unlikely, then — by golly (and never mind that it can be shown how it happened) — the process must have required assistance from the designer! Here’s more:
To answer this question, Thornton and co-author Michael Harms, PhD, of the University of Oregon focused on the glucocorticoid receptor (GR), a key protein in the endocrine system that regulates development and stress responses in response to the hormone cortisol. They resurrected the gene for ancestral GR as it existed around 450 million years ago, before it evolved its capacity to specifically recognize cortisol.
Thornton and Harms then created millions of copies of this genetic template, using a method that introduced random mutations into every new copy, thus mimicking the variation that evolution could have produced in the protein under alternative scenarios.
Thornton and Harms tested many thousands of variants but found none that restored the function of GR other than the historical mutations that occurred in actuality. “Among the huge numbers of alternate possible histories, there were no other permissive mutations that could have opened an evolutionary path to the modern-day GR,” Thornton said.
We’ve been leaving out a lot. You’ll need to read it for yourself. All we’re trying to do here is show what’s likely to excite the Discoveroids. Moving along:
While most prior discussions of historical contingency in evolution have focused on external events such as asteroid impacts, mass extinctions, climate change, Thornton and Harms showed that the intrinsic complexity of proteins as physical objects also makes evolution depend profoundly on low-probability chance events.
Obviously (a creationist will conclude), were it not for the benevolent intervention of the designer, we wouldn’t be here. Interestingly, something like that (the “we wouldn’t be here” part) is also the researchers’ conclusion. Here’s one last excerpt:
“It’s very exciting to have been able to directly study alternative ancient histories,” Thornton said. “If evolutionary history could be relaunched from ancestral starting points, we would almost certainly end up with a radically different biology from the one we have now. Unpredictable genetic events are constantly opening paths to some evolutionary outcomes and closing the paths to others, all within the biochemical systems of our cells.
So there you are. Our existence is indeed improbable, which is no surprise to anyone who understands evolution. That’s what makes us so valuable — at least to ourselves. It’s the inevitable conclusion for an evolutionist. On the other hand, an all-powerful deity could poof us into existence whenever it wished, and then obliterate us if he were in the mood to do so. Afterwards, if his mood changed, he could re-create us all over again. Nothing to it. We’re no big deal in that kind of universe, little more than a toy, with which a supreme intelligence might become bored.
But did a mysterious designer really intend for us to be here, and guide events with that purpose in mind? It wouldn’t seem so — except to a creationist, and some of them are certain to make that claim about this research. Evolution may not be predictable, but the simple-mindedness of creationists definitely is.
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