I’ve just picked up Larry Moran’s teaser “Can You Guess Who Wrote This?” on his Sandwalk blog. As the words are a restatement of Paley’s classic but long ago debunked Watchmaker analogy and the Sandwalk article is accompanied by a photograph of the paleontologist and champion of theistic evolution, Simon Conway Morris, there isn’t much of a mystery. There original article by Conway Morris, Darwin was right. Up to a point, appeared in Thursday’s Guardian as part of its Darwin 200 coverage.
Conway Morris first came to widespread public notice in 1989 when his reclassification of the Burgess Shale fauna was described enthustiastically by fellow paleontologist Stephen Jay Gould in the book “Wonderful Life” (ISBN 0-393-02705-8). Gould, whose target was what he viewed as the excessive adaptationism of contemporary biologists and thinkers such as Richard Dawkins, John Maynard Smith and Daniel C. Dennett, used the Burgess Shale fauna as an example to illustrate his view that evolution could easily have taken a very different path. Natural selection, he believed, wasn’t so strong that it led inevitably to the kind of ecology we now see in the modern world.
Gould’s primary image in this illustration was “the tape of life”.
““But if I could rerun the tape of life from the origin of unicellular organisms, what odds would you give me on the reevolution of this complex and contingent insect-flower system? Would we see anything like either insects or flowers in the rerun? Would terrestrial life originate at all? Would we get mobile creatures that we could call animals? Fine-scale predictability only arises when you are already 99 percent of the way toward a particular result — and the establishment of this 99 percent lies firmly in the domain of unrepeatable contingency.”
As he often did, Gould overstated some of his points, and his presentation has been attacked by many biologists as laying too much emphasis on the role of chance. Biologists, including Conway Morris himself, correctly point to the evidence of convergence, where natural selection has repeatedly produced similar solutions to similar problems in different situations involving creatures that are not closely related. The strong resemblance between the hydrodynamic forms of the dolphin and the shark are perhaps the most striking example of this.
For Conway Morris, however, more is at stake. As a Christian he believes that Genesis 1:27, wherein God creates man in his own image, is true, and this constrains evolution in his eyes. In the eyes of Gould, and of most biologists, the evolution of high intelligence is not inevitable. As PZ Myers has already remarked in his December, 2003 review of Conway Morris’s “Life’s Solution: Inevitable Humans in a Lonely Universe” (ISBN 0-521-60325-0), Conway believes that:
- We’re unique. Although not impossible, the odds of life arising at all are so remote that it’s likely that we’re all alone in the universe. It’s a miracle that we exist.
- We had to exist, exactly as we are. Once life exists, it must run down a foreordained track to a very specific outcome, us. Yes, bipedal, tool-using humanoids are a necessary result of evolution, and if life arose on other planets (which it didn’t, because it’s so improbable, but if it did…), there would be people living on it just like us.
This places Conway Morris at odds with most biologists, who see nothing inevitable about human beings.
Conway Morrir’s problem here isn’t so much that he’s in a minority among biologists, but that it is at all possible for biologists honestly to disagree on whether humanity was inevitable. It’s a problem because his target isn’t his fellow biologists at all, it’s atheism. In this article, and in his Boyle Lecture (PDF), Conway Morris mixes and matches scientific and theological arguments against atheism. We’ve seen it all before, of course. Darwin cannot explain everything so some of nature must be due to God; a godless world is one without morality, so God must exist or we’ll just kill one another. Weak stuff.
More recently Ed Yong in his “Not Exactly Rocket Science” blog has described, in lay terms, how a scientific experiment by Richard Lenski and others has rerun the tape of life in microcosm and eventually produced divergent results. One strain of E. Coli kept under tightly controlled conditions, developed, through a complex evolutionary path, the capacity to metabolize the citrate medium in which it was kept under anaerobic conditions. Other strains kept under identical conditions did not and (it was shown) could not develop it, because their history had led to a different accumulation of minor mutations. So Gould was right, to the extent that history does matter. Ironically, Conway Morris had earlier cited the experiment as evidence that Gould was wrong.