Re: The Baldwin Effect: What is it trying to say?


"Guy Hoelzer" <hoelzer@xxxxxxx> wrote in message
news:dnphgn$2jke$1@xxxxxxxxxxxxxxxxxxxxxx
> in article dnoioo$246p$1@xxxxxxxxxxxxxxxxxxx, Jim McGinn at
> jimmcginn@xxxxxxxxx wrote on 12/13/05 11:48 PM:
>
>> Guy Hoelzer wrote:
>>
>> <snip>
>>
>>> plastic behavior responds to environmental contingencies first, then the
>>> new
>>> phenotype becomes codified through assimilation into the genome. This
>>> is
>>> often, but not necessarily, accompanied by the evolution of morphology
>>> to
>>> permit greater effectiveness of the new behavior.
>>>
>>> This view might seem so broad as to make the BE trivial,
>>
>> It is.
>>
>> Somebody (possibly Baldwin himself) described it as having a selective
>> positive feedback aspect to it that was distinctive from that of normal
>> evolution. It doesn't. It's nonsense. Like a lot of concepts in
>> evolutionary biology, the willingness of many to believe in the
>> scientific validity of the Baldwin effect has more to do with bad
>> english than it does good science.
>>
>> Beyond that it is very hard to debate BE in that it exists only as a
>> theoretical construct.
>
> The part of my post that you copied above was followed by my argument for
> why this broad view of the BE is not trivial. I think that you should
> have
> included that argument and responded to it if you were going to stake out
> a
> contradictory view. In my argument, I described a plausible alternative
> to
> my own argument, which I see as a compelling justification for the
> non-triviality of the view that you just said was trivial.

Okay.

> This view might seem so broad as to make the BE trivial, but I don't think
> so. For example, we might consider the plausibility of a reverse BE.
> Imagine that a morphological novelty evolves without any function by a
> process like drift. What would the organism do? Consider, for example, a
> morphological macromutation of the sort that has been observed in
> Drosophila
> where legs grow in the place of antennae. I suggest that plastic
> behavioral
> potentials would lead the organism to make use of such morphological
> novelties with which their behavior has not coevolved (if possible). To
> make my example less real, but more visceral, imagine that you were born
> with a hammer at the end of your arm instead of a hand. I suspect that
> this
> would change your behavior, and that you would use your hammer in many
> novel
> and useful ways. Contrary to the BE, this would be an example of
> morphological evolution followed by behavioral compensatory evolution.
> IMHO, the real question about the BE, is which of these scenarios is more
> likely (happens more often), and why?

I agree that the scenario you suggest is plausible (temporarily putting
aside my objections to genetic drift) but it seems to me to be just plain
old natural selection. Nevertheless the plasticity of behavior associated
with culture that is found in some species, most notably the human species,
could enable what you indicate. We might refer to it at the Edward
Scissorhands version of BE. All in all, I don't see BE as representing
anything all that remarkable--it does not represent any kind of positive
feedback process distinctive from plain old NS. And this was the major
claim of BE.

Jim


.

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