Thursday, 11 February 2010

Painting a Christian Picture of Evolution

The portrayal of evolution in popular science books can often leave a bitter aftertaste in the mouths of Christians, even those who understand and accept it. Popular writing on the subject inevitably includes the biases of the writers and how they interpret meaning in light of the scientific theory. A well known example comes from George Gaylord Simpson: “Man is the result of a purposeless and natural process that did not have him in mind.” Clearly this would not be seen by a Christian as something which matches their beliefs.

Richard Dawkins is one of the most read popular authors of evolution, famed for his book “The Selfish Gene” in which this quote is found: “We are survival machines, robot machines, blindly programmed to preserve the selfish molecules known as genes.” Another which may send alarm bells ringing to Christians who have different metaphysical ideals to the author.

In contrast to this there are many evolutionary biologists who are Christians and they often present evolution in a very different manner. I want to ask if this is even necessary and if it can diminish our understanding rather than aid it. Should we sugar coat evolution to enable more Christians to find it palatable?

Opposition to evolution tends to emphasise death, competition and selfishness in order to denigrate the theory. Naturally the reaction to this is to emphasise more positive aspects such as life’s diversity, cooperation and beauty found in nature as a result of evolution. None of these factors are absent from evolution, though both are misrepresentations as they ignore the contrasting aspects of evolution by natural selection. Christians engaging with the theory should be aware of both sides and not just that which suits their agenda.

For some Christian biologists studying evolution things are a little different. Their studies have led them to the view that these more positive aspects of evolution are actually prevalent and not just an appealing gloss of paint on the veneer of the theory. Could a Christian portrayal of evolution actually be correct?

One such biologist is Martin Nowak who specialises in mathematical biology. One of his main areas of study is cooperation in evolution and the evolution of altruism. In one of his most well known papers he suggests that the evolution of complexity is made possible by cooperation and even goes on to suggest that the principles of natural selection and mutation should be accompanied by a third principle of “natural cooperation”. With evolution as a process which not only produces altruistic organisms but also functions largely through cooperation, the image of the theory is softened somewhat and is more in line with a Christian vision of the world. Whether or not Nowak is influenced by his Christian beliefs is largely irrelevant in this case, as his mathematical rigour will testify.

Similar ideas to those of Nowak come from another Christian involved in evolutionary biology, ecologist Joan Roughgarden. In her book “Evolution and Christian Faith” she suggests that the term “natural breeding” is more effective than “natural selection”. Her reasons are twofold; the term “selection” has become a more general term in common parlance, whereas “breeding” has a very specific meaning; it also de-emphasises the “survival of the fittest” aspect of natural selection which has often been misunderstood. From a Christian perspective this change would probably be for the better, but realistically it would be unlikely to ever catch on.

Roughgarden heavily emphasises cooperation in evolution and has no qualms about stating it presents a more Christian friendly view of the theory. She has also been vocal in attacking selfish gene theory and holds controversial views on sexual selection. Sexual selection explains the dimorphism between males and females (the peacock being the classic example) in terms of conflict between mates in determining the roles they play. Roughgarden proposes that sexual selection should be replaced with “social selection” in which shared effort towards a common goal is the driving force. Her emphasis on cooperation is her similarity to Nowak; however, they differ vastly on the details of how this occurs.

With regards to cooperation emphasis should certainly be placed on it, in this case both Nowak and Roughgarden are correct. However, there is the risk that cooperation will be emphasised at the expense of competition when nature readily employs both. This is a mistake which Roughgarden often makes, though whether it is due to a Christian bias is not obvious. This is a good example of a favourable principle in evolution which can be justifiably emphasised in a way which Christians may find appealing. The acknowledgement of cooperation in evolution has brought light to the theory, but it must not be overzealously emphasised to the extent that other aspects are ignored. However favourable Roughgarden’s social selection may sound, it is still a tentative and heavily controversial proposal in the world of evolutionary biology, Christians should be cautious about jumping on this bandwagon.

Orthodox evolutionary views have long held that there is no progress in evolution and that evolution is unpredictable (in the long term). The famous thought experiment of Stephen Jay Gould (and independently of Stuart Kauffman) asks us what would happen if evolution was allowed to rerun, to ‘replay the tape’ of evolution. Gould argued that life would be completely different to the diversity we see today and that the chances of anything remotely like humans emerging was slim. To Christians who believe man was both the purpose and pinnacle of creation this view is unsettling; how could God use such a random mechanism? The Christian responses to this were theological until recent years; there is now a strong scientific response which many theistic evolutionists have taken note of.

Evolutionary palaeobiologist Simon Conway Morris claims that if we were to replay the tape of evolution the outcome would be similar to what we see today, humans are near inevitable. In the eyes of Conway Morris the spectre of teleology has returned to biology. He calls on the principles of convergence and constraint in evolution to make his case. His conclusions are that the components of complex systems are inherent in simpler ones; that the number of evolutionary end-points is limited; what is possible has usually been achieved multiple times, suggesting inevitability; and that time increases probability of traits arising, trends do occur. He makes a bold case backed by an incredible amount of examples in his book “Life’s Solution” in which he presents his controversial view.

The prevalence of convergence is still open to debate but is largely accepted. The idea that sentient beings are inevitable is not as widely held, but Conway Morris is not the only one to hold it. Outside of scientific circles many Christians have embraced his views, as the idea of evolution being more convergent than contingent presents the favourable teleology many desire in a Creation showing God’s intent and will. His critics have often claimed that his Christianity causes him to pursue such a view, a claim which should be taken seriously. This is another bandwagon which Christians should not simply jump on, debate remains and at the moment Simon Conway Morris is on one extreme of a spectrum of views. Non-scientist Christians should not simply choose the extreme which favours their cherished views.

Christians involved in science are not the only ones prone to reading their own views into the history of life. Critics of Gould often pointed out his Marxist leanings and his loathing of socio-biology as the driving force behind some of his views. Bizarrely the criticism of Simon Conway Morris reading a Christian view into the history of life can also be thrown at atheist scientists who hold similar views to him, reading their own metaphysical assumptions into the theory. In “The Ancestor’s Tale” Richard Dawkins briefly discusses the question of an evolutionary rerun, citing Conway Morris as an expert witness. Although his views are not quite as extreme as those of Conway Morris, he accepts the view that replaying the tape could result in something very similar to human life. The point could be made that his atheism requires a mechanism which can produce humans with intelligence, this is evolution by natural selection, however, if it could be shown that humans were not only a product of evolution but also inevitability, then his worldview would be strengthened. The point here is that bias is often inescapable when approaching questions like these and we should try our best not to let our biases dictate what we accept.

With regards to convergence and contingency the jury is still out. Convergence is certainly showing not to be the exception to the rule, but we should not leap to the other extreme and declare it to be the rule, however pleasing to our teleological desires it may be. More data is needed, the concepts need to be debated and discussed in the scientific arena in more detail. It is likely, as with the cooperation example, that convergence is one facet. Evolutionary history is likely a complex interplay of contingent happenstance and convergence, just as it is a complex interplay of cooperation and competition.

The Christian friendly picture of evolution would seem to hold that natural breeding, random mutation and natural cooperation are the driving forces in a world full of constraints resulting in the inevitability of mankind, of altruism and of beauty. On the other extreme fierce and deadly competition driven by selfish genes results in an unpredictable array of diversity in which humans are a fortunate accident. In reality the truth is more likely to be somewhere in the middle of these caricatures. Cooperation is certainly not a peripheral occurrence; it is a key factor just as competition is. Convergence may or may not be the main theme of evolutionary history, but contingency is clearly not the only theme found.

Emphasising the Christian friendly aspects of evolution can be beneficial, but restraint must be applied. Some of the views are still being debated and are controversial; presenting these as the main thrust of evolution could be detrimental. Christians (though this applies to anyone really) should strive for the most accurate picture possible, which often sits between two extremes. We want to see the full picture, not only the nice half, our faith should inspire us to understand for truth cannot be our enemy.

For some of Nowak’s work see here: http://www.sciencemag.org/cgi/content/abstract/314/5805/1560 http://www.fas.harvard.edu/~etc/research.html
For a controversial paper on social selection by Roughgarden see here: http://www.ncbi.nlm.nih.gov/pubmed/16484485?dopt=Abstract
Reviews of her views can be found here:
http://www.the-scientist.com/templates/trackable/display/news.jsp?type=news&id=23358&o_url=news/display/23358
http://www.theamericanscholar.org/the-peacock-problem-by-long/
http://www.newscientist.com/article/mg20227066.800-review-the-genial-gene-by-joan-roughgarden.html

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