Evolution’s Place? 5

Several weeks ago we began a series looking at Simon Conway Morris’s book Life’s Solution: Inevitable Humans in a Lonely Universe. After a brief hiatus I  will come back to this book with two final posts; today a discussion of the force of his argument from convergence (Ch. 6-10, pp. 106-310), and in the next post a discussion of his chapter: Towards a Theology of Evolution.

Conway Morris is the Professor of Paleobiology at Cambridge University.  His research is focused on “the study of the constraints on evolution, and the historical processes that lead to the emergence of complexity, especially with respect to the construction of the major animal bodyplans in the Cambrian explosion.” His work is published in all of the major journals of the discipline including Science and Nature.

The central chapters of Conway Morris’s book outline (in a rather rambling fashion) the evidence for his hypothesis that evolutionary convergence is ubiquitous and that the progress of evolution, far from being random and highly contingent on chance events, is in broad brush strokes predictable.  This is not farfetched wishful thinking and others are thinking along similar lines. As an example Conway Morris quotes an article in the journal Evolution discussing the evolution of body size and its tendency to increase. The authors of this article state: “We suggest, however, that Gould’s … emphasis on randomness be replaced with an emphasis on deterministic outcomes that result largely from the role of ecological processes in speciation and extinction.” (p. 306).

Here are the questions I would like to consider today:

Is there room for randomness in your understanding of God and creation?

How much of what happens is predetermined and controlled by God? Is a process that is random in detail but globally deterministic consistent with the sovereignty of God?

In Ch. 6-10 Conway Morris looks at range of different topic and surveys convergence in biology. Convergence means that the same feature or function has developed independently multiple times. He is looking for similarities and themes. In a rather breathtaking trek (or what sometimes seems like a weakly directed random walk) he spans the range from molecular cofactors to proteins to structures to behaviors to intelligence to culture.

Simple laboratory experiments on E. coli bacteria and on Drosophila flies suggest that evolutionary change is dependent on adaptation to new circumstance not chance or history. That is, it is neither highly contingent nor chaotic.

Molecular cofactors are convergent, chlorophyll for light harvesting, retinal/rhodopsins for vision (among other things).

Protein structures and enzyme active sites are convergent.

Skeletal structures are convergent and it appears that all possible arrangements have been used.

Eyes are convergent.  They have evolved several times in only a few related forms, primarily camera eyes and compound eyes.

The sensory nervous structure for processing complex sensory signals is convergent.

Vocalization and intelligence are convergent.

Social behavior in animals is convergent – cultural behavior in hominoids is likely convergent.

So what is the big picture?

1. The evolutionary mechanism of adaptation and natural selection is an incredibly powerful method for searching the realm of biological possibility. It has an “uncanny ability to find the short cuts across the multidimensional ‘hyperspace’ of biological reality.” (p. 309)

2. Evolution is progressive, it has a global directionality.

What we do see through geological time is the emergence of more complex worlds.  Nor is this a limiting view. It might be premature to suppose that even the bacteria of today are some sort of ‘honorary fossils’, unchanged relics from the Archaean pond-scum. Nor need we imagine that the appearance of humans is the culmination of all evolutionary history. Yet, when within the animals we see the emergence of larger and more complex brains, sophisticated vocalizations, echolocation, electrical perception, advanced social systems including eusociality, viviparity,  warm-bloodedness, and agriculture – all of which are convergent – then that sounds to me like progress. (p. 307)

3. The envelope of possibilities in biology expands as building blocks become available and as the biosphere develops. Evolution is not simply mutation, it is co-option , gene duplication, and recruitment and more. Existing structures are often used for new and distinct purposes. We cannot predict the future, but we are on a directed path to the future.  Some of the ideas of emergence may come into play here.

What evolution can not do is see into the future diversification so far as the envelope of possibilities is concerned, … What we can say is that whenever the known edge of the evolutionary envelope is reached, be it in terms of intelligence or agriculture, then it will be explored independently several times. (p. 307)

4. Ultra-Darwinist fundamentalism, belief in the selfish gene alone is at best incomplete, at worst wrong; it represents an oversimplification of a complex reality.  In the writings of some it almost seems as though the genes are gods – described as ‘molecular agencies that are immortal, omnipotent, omniscient, and even immaterial.’ (p. 323)  But think about it – does this really make sense?

Outside its cellular milieu the DNA is biologically inert, if not useless. Genes may provide a switchboard for life, but the complexity of life will depend on something else: how the same genes may be recruited to make different products, how the developmental networks change and evolve, and how apparently trivial events such as gene duplication and protein isoforms open immense new territories for biological exploration. Life may be impossible without genes, but to ascribe to them powers of intentionality misses the mark. (p. 324)

5. Once life on earth began the appearance of something very like us was essentially inevitable.  Conway Morris suggests that a program of research that explores not only the results of evolution, but also the phenomenon of evolution itself, will discover just this (and he is not in the majority, but also not alone in this belief).

It is my suspicion that such a research programme might reveal a deeper fabric to biology in which Darwinian evolution remains central as the agency, but the nodes of occupation are effectively predetermined from the Big Bang.

One such node is, of course, that of the humanoid, and from the present evolutionary perspective we are undeniably unique. Yet, as I have already argued, if we had not arrived at sentience and called ourselves human,  then probably sooner rather than later some other group would have done so, perhaps from further afield, even from much further afield. (p. 309-310)

In the next post I will conclude with Conway Morris’s reflections on theology, but for now I will rephrase the questions above.

What does it mean to be human? Did God design details (five fingers, one liver, and wisdom teeth) or is it enough to have designed sentience, consciousness and intelligence, capacity for love and relationship?

Is ‘deterministic’ evolution consistent with a robust theology?

If you wish to contact me directly you may do so at rjs4mail [at] att.net

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