"Our work demonstrates a fundamental error in the current challenges to Darwinism," said Thornton. "New techniques allowed us to see how ancient genes and their functions evolved hundreds of millions of years ago. We found that complexity evolved piecemeal through a process of Molecular Exploitation -- old genes, constrained by selection for entirely different functions, have been recruited by evolution to participate in new interactions and new functions."That's what's wrong with the ideas behind "Creationism" or "Intelligent Design." The people pushing those ideas grab onto something they cannot find a rational explanation describing the process of evolution for, then state that only supernatural processes can have caused the end result.
The scientists used state-of-the-art statistical and molecular methods to unravel the evolution of an elegant example of molecular complexity – the specific partnership of the hormone aldosterone, which regulates behavior and kidney function, along with the receptor protein that allows the body's cells to respond to the hormone. They resurrected the ancestral receptor gene – which existed more than 450 million years ago, before the first animals with bones appeared on Earth – and characterized its molecular functions. The experiments showed that the receptor had the capacity to be activated by aldosterone long before the hormone actually evolved.
Thornton's group then showed that the ancestral receptor also responded to a far more ancient hormone with a similar structure; this made it "preadapated" to be recruited into a new functional partnership when aldosterone later evolved. By recapitulating the evolution of the receptor's DNA sequence, the scientists showed that only two mutations were required to evolve the receptor's present-day functions in humans.
"The stepwise process we were able to reconstruct is entirely consistent with Darwinian evolution," Thornton said. "So-called irreducible complexity was just a reflection of a limited ability to see how evolution works. By reaching back to the ancestral forms of genes, we were able to show just how this crucial hormone-receptor pair evolved."
There are is a major problem with this form of thinking. Since it cannot currently be explained, the Creationists/ID'ers assume that it can never be explained. Thus they shut off all study into rational explanations. This keeps such people from learning the rational explanation for the development of something. Then, since all attempts to learn the explanation are stifled, it becomes a self-fulfilling prophecy. It prevents understanding of the rational process, and failure to understand the process is used to prove that only supernatural ("magic") processes could have created the current result.
Creationism should never be taught in introductory science classes (everything prior to graduate school) since it is magical thinking. Science is a rejection of magical thinking, and introductory science classes teach scientific thinking.
[Thanks to Daily Kos]
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