Re: Genes and Development Conference

Brian D Harper (
Fri, 02 Apr 1999 21:21:26 -0800

At 12:11 AM 4/2/99 -0500, Tim wrote:
>Brian wrote to Kevin...
>> But I don't think your answer is quite to the point I was
>> trying to make. How could we predict ancestry ["how a new species
>> would evolve from an old species"] from a theory which decouples
>> form from ancestry?
>Genetics, molbio, biochemistry... There is no reason to assume that
>the decoupling will occur at all levels. And there are many good
>reasons to think this is not the case.
>Earlier Brian included exerpts from Webster and Goodwin:
>"We suggest that what is required is the development of a specific
>causal-explanatory theory of form, a theory of morphogenesis
>in the most comprehensive sense, and that such a theory will
>be as fundamental to biology, if not more so, at least as
>the theory of evolution. We contest the current view that
>such a theory is merely a supplement to the theory of
>evolution and, consequently, that it should be couched in
>terms of a 'genetic programme'. [...]"
>This is where I think Goodwin et al are guilty of making a bit of a
>strawman, re: evolution & genetic programs. Most biologists/biochemists
>(& etc) have understood for years that simply knowing gene sequences or
>"genetic programs" would only provide one part of the puzzle. One reason
>why molecular biology has had so much airtime is that it has gotten _so
>much easier_ to do. We simply focus on the problems that have accessible
>solutions. Molbio also provided us with tools to crack problems that we
>couldn't before. But through this whole process, most of us stayed grounded
>in the understanding that having sequence data alone will not answer many
>of the questions we're interested in. We knew that "pacman" models of
>transcriptional activators only told a part of the story. We knew that
>genomics is of limited use in studying things like the mechanics of
>metabolism. So when people like Goodwin rail against the dogmas of gene-
>centricity, I think that they should be submitting their comments to
>"Duh!" the scientific journal of the bloody obvious (I've made similar
>comments of Coyne's writings previously). Sure, it's an easy rhetorical device
>to make a boogeyman of genetic programs, but that's not a dogma held by most
>of the biochemists I've encountered.

Hello Tim. I appreciate your comments a great deal but am a little
confused. I believe that everybody knows (including Goodwin) that
everybody knows that there are factors involved in addition to the
genetic programs. I thought it clear enough from the quote that the
point of contention is the relative importance of the genetic program.

I'm sure there are a wide range of views as to how important this is.
At one extreme one has the selfish gene (I recall Dawkins saying that
organisms are just survival machines constructed by genes) and at the
other end people like Goodwin.

I'm happy to hear what you say about "most of the biochemists you've
encountered". It seems to me quite often that what laymen like myself
hear the most about are the extreme views (Dawkins or Goodwin) and
not enough about the middle of the roaders which hopefully make up
most scientists. Nevertheless, I do not believe that the view that
development is most predominantly (but not exclusively) directed by
a genetic program is a strawman. Goodwin gives several quotes in his
book supporting this view, for example:

"[The] collection of chromosomes in the fertilized egg constitutes
the complete set of instructions for development, determining the
timing and details of the formation of the heart, the central nervous
system, the immune system, and every other organ and tissue required
for life." -- C. Delisi

"DNA provides the programme which controls the development of the
embryo and brings about epigenesis." -- Wolpert

"A theory of development would effectively enable one to compute
the adult organism from the genetic information in the egg."
-- Wolpert

Just to check if one had to really dig for such quotes, I took a
look at <The Shape of Life> by Rudolf A. Raff. All I had to do was
look in the index under "gene" and then the subtopic beneath
"assuming primacy in developmental biology" which led me to the

"Genes are important because they are the controllers and executers
of developmental processes." -- Raff

>These people (Goodwin et al.) make grandiose statements about where their
>"new" paradigms will take them in answering the mysteries of life -- but
>inevitably their concepts are absorbed and assimilated (or spit out) without
>the predicted bloodbath of a violent revolution. Hardcore biochemists are
>like the Borg, and as difficult to impress.

Yes, well this is often what happens. But I personally believe that
science is enriched by this process and that people like Goodwin are
needed for this enrichment, even if they turn out to be wrong. It is
the rare individual that will risk everything by doing something
really daring. Reminds me of something Einstein said. Something to
the effect that most scientists are like carpenters who look for the
thinnest section in the board and then drive a great number of nails
through it.

>- "Did you know that your old vacuum doesn't sweep up everything? There are
> carpets that don't work according to models of simple Mendelian
>- "Well, 'Duh!' That's why we're picking up some things slowly, by hand. Have
> you got anything that works better?"
>- "Err, no, not yet, but we're developing specs for a holistic megafield
> It will be powered by a platonic generator so you'll never have to worry
> tapping into messy historical contingencies ever again. It's vaporware at
> moment but I promise we'll have an alpha version out real soon, anytime now.
> But, I'm so sure that it will completely supplant anything else on the
> market that I think you should get your order in, TODAY!...
> how many of these new babies should I put you down for?"
>[a door] *Slam!*

A humorous story Tim, but I believe you're erecting your own strawman :).

Brian Harper
Associate Professor
Applied Mechanics
The Ohio State University

"All kinds of private metaphysics and theology have
grown like weeds in the garden of thermodynamics"
-- E. H. Hiebert