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| "Aeginura grimaldii by Ernst Haeckel |
On March 16th, I attended a talk hosted by the Tulane
Philosophy Club. Our speaker, Ilya Dubovoy, a medical student at Tulane,
attempted to explain some potential problems with the current understanding of
Evolutionary Theory, especially in terms of the randomness or tailored-ness of
genetic mutation in response to environmental stress or change.
I was left completely nonplussed by the talk. Its essence
was a set of claims about evolution, which is to say about biological science,
so why was it presented in a forum on philosophy? It is not at all clear why
anyone would expect a vague and preliminary idea about evolutionary
biochemistry to inform the field of philosophy. And beyond the basics of
epistemology – which were not discussed – it is not clear what philosophy could
bring to an observational and experimental issue in science. The speaker had to
take some criticism, but that would have been far harsher from an audience
of biologists, and I could not help but suspect that he was seeking friendlier
shores for a concept he knew would be met with intense skepticism by its proper
audience.
***
***
The kernel of an idea that I was able to extract from the
talk is that there is, perhaps, evidence that a tendency for genetic change
(mutation) is sometimes directed toward narrow parts of the genome (an
organism’s set of genes) in specified response to particular environmental
changes or stress. Dubovoy used the unfortunately loaded term “teleology” to
describe this tendency, but I think those of us who are involved in
creationism-evolution debates have to be careful not to overreact to that. He
seemed to mean by “teleology” that environmental changes somehow direct a
tendency to mutate toward sections of the genome that are relevant to that
environmental change, and not to imply the usual creationist miscomprehension
of evolution, in which “teleology” means that evolution accumulates changes
over centuries or millennia toward some future form or other biological goal.
To make this idea of directed mutation more than just the
earliest stages of a preliminary notion, Dubovoy would have to propose a host
of additional details. By what mechanisms do changes in the environment
generate molecular (chemical) signals identifying those changes to a cell,
organism, or population? How and where are those molecular signals interpreted
as referring to or implicating a particular, narrow section of the genome? What
physical-chemical processes then bring about mutations in the implicated
section of the genome? Most importantly, is he proposing that this mechanism
generically increases mutation in the implicated portion of the genome, or that
it somehow narrows or pre-selects those mutations to fit the signaled
environmental changes (a critical detail about which he was frustratingly vague)?
It was difficult to understand how many of Dubovoy’s points
were supposed to relate to his kernel of an idea. He seemed to think there was
something dramatically new and threatening to evolutionary theory in the fact
that individual organisms sometimes form cooperative groups, that chemical
signaling may activate or deactivate the expression of existing genes, that
lateral transfer of genes sometimes happens between species, or that mutation
is random only in the sense of “unpredictable,” and not in the sense of “evenly
distributed.” None of these facts are news to evolutionary biologists, and none
of them imply a problem with the existing theory of evolution, at least not
insofar as Dubovoy was able to clarify.
Dubovoy explicitly denied being a creationist, and made no
directly creationist claims. However, it seems to me that his proposed
“teleology” comes far closer to creationism than he himself realizes. Like
creationists, he is claiming that micro-evolution, the slow accumulation of
small, undirected changes over long periods of time, is insufficient to explain
the diversity of life we see around the world today and in the fossil record.
And like creationists, he is hopelessly vague about the supposed limits of
micro-evolution, refusing to quantify what micro-evolution can and cannot do, or
how his proposal of more directed mutation supplies the missing quantity.
Perhaps, in some years, he’ll have thought this out more
carefully.
~Jim Dugan
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