James Shapiro: Intelligent Design “Has a Valid Point with Regard to the … Limits of Neo-Darwinism”
Earlier this year, the National Association of Scholars recently published an interesting issue of their journal Academic Questions. It’s on a special theme, “The State of Evolution,” and it includes many articles that are worth reading. One article, by University of Chicago biologist James Shapiro, is titled, “Evolution Is Neither Random Accidents nor Divine Intervention: Biological Action Changes Genomes.” Shapiro provides a very nice review of various functions that have been discovered for transposable elements — a type of repetitive DNA that was once labeled “junk,” but which we now know is “needed for various aspects of genome function.” He writes:
[R]epetitive DNA was labelled as “junk DNA,” “selfish DNA,” or “selfish genetic elements.” Richard Dawkins famously erected a widely popular philosophy of evolution on the basis of “The Selfish Gene” (1976).
Today, we recognize that most of this repetitive DNA is made up of transposable elements and other repeats needed for various aspects of genome function, especially developmental regulatory networks controlling cellular differentiation. The repeats help guide the origin of cell lines that comprise distinctive tissues, say bone tissue versus nervous tissue. Both have the same DNA, yet each cell type expresses the genome in distinctive ways controlled by different DNA repeats.
A Curious Comment
I highly recommend the paper. It also includes a curious comment about intelligent design:
Support for evolution guided by divine intervention has a toehold in the quasi-scientific Intelligent Design (ID) movement, initiated by Michael Behe (“Darwin’s Black Box: The Biochemical Challenge to Evolution,” 1996) and carried on by members of the Discovery Institute and other creationist think tanks. The basic argument that ID theorists make is that natural selection of random hereditary changes cannot produce genomes capable of expressing all the intricate networked adaptations modern molecular biology has revealed to operate in living organisms. This conundrum is, in Behe’s words, “irreducible complexity.” Hence, the ID theorists posit a need for divine intervention.
The ID argument has a valid point with regard to the explanatory limits of neo-Darwinism, still widely regarded as the only legitimate scientific explanation of evolution. ID falls down by assuming (as do mainstream evolutionists) that genome change occurs from outside the boundaries of life itself. Within the scientific community, there is agreement that the hereditary variation necessary for evolutionary change occurs by natural means. But significant difference exists between scientists about what constitutes “natural means.”
Shapiro is a great biologist who has offered many keen insights into the nature of genomic functioning. He’s clearly not an ID proponent and that is fine. I would disagree with his characterization of ID as a negative argument against evolution in favor of “divine intervention.”
The Struggles of Neo-Darwinism
But he’s absolutely correct to note that neo-Darwinism struggles to account for the “intricate networked adaptations modern molecular biology has revealed to operate in living organisms.” And I appreciate his recognition that ID got this one right. Shapiro thinks that natural genetic engineering can account for many of this intricate complexity — and we in the ID movement are interested in seeing how far these mechanisms of pre-programmed evolution can take us.
For my part, I think they might be useful for fine-tuning pre-existing functions — and may be involved in what Emily Reeves recently wrote about as “continuous environmental tracking.” But I’m skeptical that Dr. Shapiro’s model can account for much of the basic complexity of life. For the moment, I’m content to be grateful to him as a non-ID scientist who recognizes something ID has gotten right.
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