October 22, 2005


Missing links: Proponents of Intelligent Design have exploited a vexing question at the heart of Darwin's theory. Now, say two leading biologists, scientists can - and must - answer back. (Peter Dizikes, October 23, 2005, Boston Globe)

As it happens, [Marc Kirschner, founding chair of the Department of Systems Biology at Harvard Medical School] and [John Gerhart, a biologist at the University of California, Berkeley] give several of these advances in evolutionary biology a broad public airing as coauthors of a new book, ''The Plausibility of Life," published this week by Yale University Press. In it, they discuss the origins of complicated biological features-from the bat's wing to the human eye-and present their theory of ''facilitated variation," which they believe addresses a major question in evolution: How can small genetic changes develop into complex, useful body parts? In a sign of the times, they also rebut claims of irreducible complexity made by Intelligent Design advocates.

In so doing, Kirschner and Gerhart say, they are tackling an issue evolutionists have often left unexamined. ''The question of how variation could be produced has been there from the beginning," says Gerhart, referring to the publication of Charles Darwin's ''On the Origin of Species" in 1859. By the 1940s, the so-called ''Modern Synthesis" of evolutionary theory powerfully buttressed Darwin's insights on natural selection with the post-Darwinian discoveries about the mechanisms of heredity. But, the authors write, the Modern Synthesis was ''silent" about the way organisms generated variation. It is not coincidental, they add, that because ''variation is the least understood of the theoretical underpinnings of evolutionary theory," it thus ''is currently the favorite target" of creationists.

Kirschner and Gerhart say this situation has now changed. Organisms, they assert, have a far greater capacity to generate rapid and complex variations than even biologists had previously supposed. Moreover, from the genetic level up to our visible features, organisms have a modular structure. In this sense, complex features are less like singularly intricate structures than a collection of building blocks.

Significantly, Kirschner and Gerhart write, while random genetic mutations in our DNA code cause variations, these mutations do not create random effects (a traditional working assumption of many evolutionists). Instead, all organisms have maintained an essentially intact set of vital mechanisms-metabolism, reproduction of DNA, growth mechanisms, and more-for at least 2 billion years. These elements, along with a long-conserved body plan common to many animals, serve as the platform for subsequent, often more visible variations.

Consider the elephant's trunk, the elk's antlers, and the narwhal's tusk, which all appear to be distinct, complex innovations. But as Kirschner and Gerhart point out, the same type of cell guided their growth in each animal. Moreover, the modular structure of life means these body parts could develop without affecting the rest of the organism. (A corollary is that it only takes limited genetic changes to bring about large bodily changes.) So the trunk, antlers, and tusk are really just different expressions of the same type of genetic activity-funneled through the process of natural selection, in which variations useful to a particular environment tend to survive over time.

Kirschner and Gerhart also suggest Behe does not consider modularity in his claim that only ''staggeringly complex biochemical processes" lie behind the composition of, say, an eye. As they note, the eyes of insects and mammals, each of which appear to be singularly complex, share important biochemical building blocks and connections among their components.

''People should be asking about the nature of complexity, not just how complex it is," amplifies Kirschner, in conversation. ''You look at a clock, and you see that every part is purposely made. That's what you would do if you were an Intelligent Designer. But instead, when you look at biology, you find that there are very few types of parts, and they are being co-opted from one place to another. We have a Lego-like capacity to very easily generate new structures."

Amazing how often their own metaphors drive Darwinists into the Creation corner. The fact that life resembles a Legoi kit in which every finished pieve can be made from a few basic pieces assembled in different ways is clear enough, but note too that when watches had gears all our machines were pretty similar and not that our watches are digital and electronic all our other machines are likewise. The very sameness and invariability of biological structures suggests design.

Posted by Orrin Judd at October 22, 2005 11:56 PM

Does pattern equate to design, and does design necessarily imply designer?

Posted by: ghostcat at October 23, 2005 12:18 PM

Of course it implies, doesn't mean it's so though.

Posted by: oj at October 23, 2005 12:33 PM

One must insert one's assumptions to connect the dots.

Posted by: ghostcat at October 23, 2005 2:22 PM

From "Finding Darwin's God", a book by Kenneth Miller (evolutionary biologist AND devout Catholic):

"Intelligent design does a terrible disservice to God by casting him as a magician who periodically creates and creates and then creates again throughout the geologic ages. . . . God is not a magician who works cheap tricks. Rather, His magic lies in the fabric of the universe itself."

The Catholic Church has never had a problem with evolution. The Pope a few years ago described it as being "more than a theory". For the cautious Vatican, this amounts to a ringing endorsement. As long ago as the 6th century St. Augustine of Hippo speculated that organisms changed form over time, though he didn't have any kind of fossil record to back up his claim. The idea that science and religion need not be antagonistic and can be compatible can be traced back to St. Augustine, who cautioned Christians that they would subject their religious faith “to scorn” if they used the Bible to make scientific observations.

Creationists should read Augustine before they make fools of themselves.

Posted by: Anon at October 23, 2005 6:46 PM

All evolutionary theories are ultimately just different spins on Genesis. Darwinism happens to be the most obviously wrong one and a cause of evil to boot.

Posted by: oj at October 23, 2005 7:40 PM

The ID pushers really need to differentate more clearly between evolution and 'darwinism'.

Posted by: Mike Earl at October 23, 2005 8:03 PM


Don't assume they get the difference.

Posted by: oj at October 24, 2005 7:59 AM
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