In popular imagination, even the imagination of of many trained in technical fields, evolution is a messy, chaotic, highly contingent and random process. Mark Whorton in Peril in Paradise comments that while he finds the evidence for an old earth convincing, the evidence for evolution is far less convincing. Most importantly, as a Christian he does not think that the origin and diversity of life is some lucky accident.
Is the acceptance of evolution a commitment to contingent randomness?
This image of randomness in evolution was made most emphatically by Stephen Jay Gould. Run the tape over and something entirely different will emerge. From his 1994 article in Scientific American (v. 271, pp. 84-91) The Evolution of Life:
History includes too much chaos, or extremely sensitive dependence on minute and unmeasurable differences in initial conditions, leading to massively divergent outcomes based on tiny and unknowable disparities in starting points. And history includes too much contingency, or shaping of present results by long chains of unpredictable antecedent states, rather than immediate determination by timeless laws of nature.
Homo sapiens did not appear on the earth, just a geologic second ago, because evolutionary theory predicts such an outcome based on themes of progress and increasing neural complexity. Humans arose, rather, as a fortuitous and contingent outcome of thousands of linked events, any one of which could have occurred differently and sent history on an alternative pathway that would not have led to consciousness.
The idea that we are products of random chance and historic contingency seems at odds with any reasonable Christian theology. But evolution is not a random process where just anything can happen. Evolution is constrained by chemistry and physics. Historical contingency may well play a much smaller role in the diversity of life we see around us than suggested by Gould. Simon Conway Morris and Ard Louis, professors at the University of Cambridge and the University of Oxford respectively discuss randomness and convergence in the video below:
The point being made in this clip is that the scientific definition of randomness does not imply that something is is open-ended and purposeless. The evolutionary process is an efficient search algorithm optimizing for specific functions. In fact, the evolutionary process follows well defined roads and paths constrained by the nature of chemistry and physics. Not everything is possible, there are a limited number of possible solutions, stable points in biological space. There is no reason to conclude that evolution demonstrates that we are accidents of nature.
If we look carefully at the chemistry of life we can go much deeper than this. Chemistry (and physics) constrain the realm of biological possibility. I recently received a new book A World From Dust: How the Periodic Table Shaped Life (Oxford University Press) by Ben McFarland that digs into this question of chemistry, biology and evolution. McFarland is a biochemist, and a professor and chair of the department of chemistry and biochemistry at Seattle Pacific University in Seattle Washington. He received his Ph.D. in Biomolecular Structure and Design from the University of Washington in 2001 and has been teaching at SPU since 2003.
McFarland’s take on evolution and contingency comes from his understanding of chemistry and biochemistry. Continue reading