Teleology and evolution

by Neil Rickert

A review of James Shapiro: “Evolution: A View from the 21st Century”

I recently “purchased” a copy of the Kindle version of Shapiro’s book, at a time when the price was zero.  My interest in this book has been piqued by claims from creationists and ID proponents, that Shapiro’s work supports their views.  In my opinion, the creationists and ID proponents are mistaken about this, though Shapiro does say things that make him sound open to ID.  When mentioning this Amazon offer, Jerry Coyne said “Jim Shapiro is heterodox in his views and opposed to much of modern evolutionary theory, so this may be a strange book.  Weigh in if you’ve read it.”  This review is my weighing in.

Shapiro is very clear that he supports evolution:

The one issue that has effectively been settled in a convincing way is the evidence for a process of evolutionary change over the past three billion years. (lines 2358-2359)

Note that references are to Kindle locations, which appear to be line numbers.

As far as I, as a non-biologist, am able to tell, Shapiro is not intending to overthrow biology.  He makes frequent references to the research literature.  What is clear, however, is that he is not happy with the way that evolution is often described.  He would prefer to replace the traditional neo-Darwinist account with a more teleological account.

The intelligent cell

Shapiro begins by making a case for cells as intelligent.  He sees this as being in opposition to a mechanistic account.

The contemporary concept of life forms as self-modifying beings coincides with the shift in biology from a mechanistic to informatic view of living organisms. (lines 336-337)

I’m a bit puzzled by this, for I am not convinced that there was ever an entirely mechanistic view.  For myself, I have always thought of biological cells as sophisticated systems, and of the DNA or genes as telling only a part of the story.  There’s a lot of use of teleological language within biology, and there is even a special term “teleonomy” introduced to talk about apparently purposeful behavior, while avoiding any appeal to vitalism.

Shapiro goes on to say:

Living cells do not operate blindly. They continually acquire information about the external environment and monitor their internal operations. Then they use this information to guide the processes essential to survival, growth, and reproduction. Cells constantly adjust their metabolism to available nutrients, control their progress through the cell cycle to make sure that all progeny are complete at the time of division, repair damage as it occurs, and interact appropriately with other cells. (lines 381-384)

The book illustrates this point with a number of examples.  Once again, that statement agrees with the view that I already had of biological cells.  And that leaves me puzzled as to what Shapiro is actually arguing.

A section of the book discusses “The Genome as a read-write storage system.”  That description seems misleading to me.  It reminded me of earlier ideas that memory might be encoded in RNA.  However, further research discredited those ideas.  Shapiro is actually talking about more basic ideas, but I don’t see those as making the case for the genome as a storage system.

Clearly, Shapiro is making the case for something like intelligence within biological cells and groups of cells.  He is also arguing that genetic change is not the mutation as copying error that is often described.  He points to evidence of horizontal gene transfer (between organism), of symbiotic unions (as argued by Lynn Margulis), and of transposals (movement of genes from one part of the genome to another).

When Shapiro says

Prokaryotes frequently use horizontal transfer to tailor their genomes for particular ecological opportunities. (lines 1723-1724)

I am inclined to think that he is overstating his case.  That description seems to imply a conscious intent of the prokaryotes (such as bacteria) to modify themselves to better exploit an observed opportunity.  Count me as skeptical that anything of the kind is going on.  And that brings us to Shapiro’s use of teleology.

Shapiro on Teleology

In comparing cells with intelligent humans, Shapiro says:

Although they may go through many trial-and-error steps, human engineers do not work blindly. They are trying to accomplish defined functional goals. Can such function-oriented capacities be attributed to cells? Is this not the kind of teleological thinking that scientists have been taught to avoid at all costs? The answer to both questions is yes. (lines 2503-2505)

Well, sure, one can attribute that to cells.  But if this is mere empty attribution, then it serves no scientific purpose.  If one wants to say that cells “are trying to accomplish defined functional goals,” then one has an obligation to demonstrate that there are such defined functional goals.  I am not persuaded that Shapiro has met that obligation.  I don’t have a problem with the idea of trial and error steps, nor with the idea that the cell has a way of evaluating a trial.  But count me skeptical on the idea that there are defined functional goals.

From the foregoing, then, it should be evident that the concept of cell-guided natural genetic engineering fits well inside the boundaries of 21st Century biological science. Despite widespread philosophical prejudices, cells are now reasonably seen to operate teleologically: their goals are survival, growth, and reproduction. (lines 2514-2516)

Cells do indeed tend to behave in ways that promote survival, growth and reproduction.  But does that observed behavior suffice to credit them with having those as defined functional goals?  If those were defined functional goals, then that would suggest that biological organisms should be able to adapt by themselves to environmental changes, and to thereby evade the effects of natural selection.  If Shapiro is right, why do we see natural selection in action?

Living cells and organisms are cognitive (sentient) entities that act and interact purposefully to ensure survival, growth, and proliferation. They possess corresponding sensory, communication, information-processing, and decision-making capabilities. (lines 2616-2618)

When I watch a bee or an ant or even a fish, I wonder whether we should consider it sentient (or cognitive).  I don’t know how we could tell.  I’m inclined to guess that there might perhaps be some glimmer of sentience, but that is no more than a guess.  If there is no way to tell even for a fish, how much harder to tell for a cell?  It seems to me that Shapiro is making statements that go far beyond what he is able to determine.

Summary

This is a somewhat strange but interesting book.  I did learn some things about what is going on at the cell level.  However, in my opinion, Shapiro fails to make a persuasive case for his view of evolution.

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One Comment to “Teleology and evolution”

  1. Challenge everything. A study of evolution has proved that flight is impossible: it is a scientific fact that despite the widespread availability of extension ladders, no part of the fossil record has been found in the air. After all, despite what they show on TV, have you ever met anyone who claims to have flown. No they all know someone who knows someone ho claims to have done so.

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