If not for a virus, none of us would ever be born.

In 2000, a team of Boston scientists discovered a peculiar gene in the human genome. It encoded a protein made only by cells in the placenta. They called it syncytin.

The cells that made syncytin were located only where the placenta made contact with the uterus. They fuse together to create a single cellular layer, called the syncytiotrophoblast, which is essential to a fetus for drawing nutrients from its mother. The scientists discovered that in order to fuse together, the cells must first make syncytin.

What made syncytin peculiar was that it was not a human gene. It bore all the hallmarks of a gene from a virus.

Continue reading “Mammals Made By Viruses”

I’ve written a few times here about the ongoing work of Joe Thornton, a biologist at the University of Oregon and the Howard Hughes Medical Institute. Thornton studies how molecules evolve over hundreds of millions of years. He does so by figuring out what the molecules were like in the distant past and recreating those ancestral forms in his lab to see how they worked. I first wrote about his work looking at how one molecule in our cells evolved from one function to another (herehere, and here). [Update: These links are now fixed.]

Most recently, I wrote in the New York Times about his latest experiment, in which he and his colleagues found that the evolution from the old function to the new one has now made it very difficult for natural selection to drive the molecule back to its old form. Its evolution has moved forward like a ratchet.

Thornton’s new work turned up last week on a web site run by the Discovery Institute, a clearinghouse for all things intelligent design (a k a the progeny of creationism). Michael Behe, a fellow at the Institute, wrote three posts (herehere, and here) about the new research, which he pronounced “great.”

This is the same Michael Behe who, when Thornton published the first half of this research, declared it “piddling.”

Why the change of heart? Because Behe thinks that the new research shows that evolution cannot produce anything more than tiny changes. And if evolution can’t do it, intelligent design can. (Don’t ask how.)

I pointed out Behe’s posts to Thornton and asked him what he thought of them. Thornton sent me back a lengthy, enlightening reply. Since the Discovery Institute doesn’t allow people to comment on their site, I asked Thornton if I could reprint his message here.

Continue reading “The Blind Locksmith Continued: An Update from Joe Thornton”

 

On Thursday I wrote about a new paper reporting the reconstruction of a 450-million year old hormone receptor, and experiments indicating how it evolved into two receptors found in living vertebrates such as ourselves.

On Friday I took a look at the initial response to the paper from intelligent design advocates at the Discovery Insitute. They claim that there exist biological systems that show “irreducible complexity,” which could not possibly have evolved. In response to the new research, intelligent design advocates claimed that hormones and their receptors do not actually make the cut as irreducibly complex systems. But to do so, they had to ignore their own published definition of irreducible complexity.

As I mentioned on Friday, the Discovery Institute promised more, and more they have delivered. Not scientific papers published in peer reviewed scientific journals, of course, but a lot of press releases and such. There’s a lot to wade through as of Sunday evening, and no doubt even more to come. But none of it amounts to much. They spend a lot of time rehashing their claim that irreducible complexity is not touched by this research. And they also use another standard strategy: raising doubts about whether a particular evolutionary scenario could take place, or whether biologists have done enough work to make their case.

Continue reading “The Final Adventures of the Blind Locksmith”

Yesterday I  blogged  about a new study in which scientists reconstructed 450 million year old proteins in order to trace the evolution of some receptors for hormones. The paper itself does not comment on the implications these results have for intelligent design, which claims that some biological systems are too complex to have evolved. But in the accompanying commentary, Chris Adami does. (Adami is the brains behind Avida, an artificial life program that I wrote about in Discover in 2005.) He writes,

Although these authors have not directly addressed this controversy in the discussion of their work–because the work itself is intrinsically interesting to biologists–such studies solidly refute all parts of the intelligent design argument. Those “alternate” ideas, unlike the hypotheses investigated in these papers, remain thoroughly untested. Consequently, whatever debate remains must be characterized as purely political.

Continue reading “The Blind Locksmith Continued: The Mushy Definition of Complexity”

Over the last few years, scientists have figured out how to recreate biological molecules that were last seen on Earth hundreds of millions of years ago. Until now, scientists have reconstructed ancient proteins to gather clues about life was like long ago. But now some scientists at the University of Oregon have done something new with these old proteins: they used them to figure out how evolution produces complex systems–exactly the sort of systems that creationists would have us believe cannot evolve.

Continue reading “The Blind Locksmith”