Re: Gould, Science, Mistakes and ....
Bryant (mycol1@unm.edu)
19 Aug 1996 00:49:36 -0600
In article <3217E019.211A@best.com>,
Joel and Lynn Gazis-Sax <gazissax@best.com> wrote:
>Bryant wrote:
>> If that's all [Gould] had done, he wouldn't have so annoyed his peers with
>> that essay.
>
>The reason why he annoyed his peers is that he doesn't buy the adaptationist
>gospel that these things appeared for a purely functional reason and continue
>to exist for a purely functional reason.
That in of itself would only be annoying in that it ignores so much of
what evolutionary biologists have found about the nature of nature.
Helena Cronin nicely outlines a few of the mistakes that have been made
by those wrongly assuming that a given trait has *no* functional
significance. (Cronin, _The Ant & the Peacock_, 1994?)
Also, depending on the trait, there's good reason to expect mutation
accumulation to "degrade" traits not maintained by natural selection. So
the "continued to exist for a ...functional... reason" comment above
actually brings up an interesting area of evol. biology.
>> He tested the /reasoning/ behind the responses. I think that is what you
>are missing. Gould's beef is with the concept of "design in nature".
I agree that Gould's beef is with what he sees as an over-application of
the notion of adaptation by natural selection by evolutionary biologists,
but I don't think he really has a beef with the notion of adaptation
("design") per se.
>> Evolutionarily, I think it's doubtful you could reproduce without a male
>> orgasm occuring.
>
>Where did I say that males could reproduce without orgasm? (Hmmmm, actually
>with sperm banks, they can. Just takes a needle if the going is rough. And
>men do turn to this if either the peer pressure or the desire to enjoy children
>is strong.)
You said that orgasm may be a side effect of copulation, not functional. I
extrapolated. Mia culpa.
>> But the fact that female orgasm is patterned in such a
>> way as to retain sperm from healthier males, rendering it a fitness
>> enhancer.
>
>I can think of many means for reproduction to occur without the pleasureable
>side effect sensations of orgasm.
Indeed. But if a woman is mating with more than one mate, she is more
likely to retain the sperm of the one inducing orgasm. As it turns out,
this is the male with the highest developmental stability, if college
students are any indication of our species' tendencies (see Thornhill et
al. 1995, December issue of _Animal Behaviour_).
There's also some evidence in the composition of human male ejaculates to
suggest that ancestral females *did* mate with more than one male... we
appear to have non-fertile sperm with elongate tails that function as
"kamikaze" or blocking sperm, which don't permit other guys' sperm to
pass. This would afford first-ejaculators a "sperm precedence" advantage
over a female's subsequent lovers. (I can dig up Baker & Bellis' ref on
this if anybody desires.)
>Fitness enhancer: my willingness to buy this is whether you are willing
>to agree that the evolution of a pleasureable orgasm is not part of a natural
>design or not.
I think that you mean by the above that my argument hinges upon an
acceptance that orgasm is an evolutionary "fitness enhancer" (aka, Adaptation).
That's incorrect, however. Study has shown that female orgasm is
patterned--copulatory orgasm occurs most often with fellows of high
developmental integrity (we can discuss just what developmental integrity
is, and why it's evolutionarily relevant, if anybody wishes).
That's evidence supporting the notion that female orgasm is (or was,
evolutionarily) functional. It was a prediction derived from an
adaptationist hypothesis of female orgasm, not a presumption of that notion.
>The key word is design, implying intent.
Function of the heart, or any other biological adaptation, does not imply
an intelligent creator. Is that what you mean? If that were the case,
Darwin's ideas wouldn't have threatened creationists. They did, because they
offered an alternative to "creation by design"--the idea that for every
"watch", there must be an intelligent watch-maker. Darwin
showed how this need not be true with organisms. (Another nice topic for a
more thorough exchange, if you wish.)
>Whether the G word
>you use is the Creationist's God or the sociobiologist's anthropomorphized
>Gene, you are falling into the trap of design (which is not pure evolutionary
>thinking) when you talk about function. I will happilly agree that there is
>a /pattern/ that is formed by the effects of pleasureable orgasm, but to attribute
>this to a will on the part of the gene is far-fetched.
Well, of course, I agree. I think you must have read some of Dawkins'
writing, and taken him too literally. He doesn't (and no sociobiologist
does) really think there's some agency of intent in DNA. He does get
almost careless with his use of metaphor in this regard, though.
>> Quality is as important as quantity. Producing healthy children that are
>> likely to survive is as (or more) vital as maximizing the number of
>> embryos produced.
>
>So what is the relevance of this statement? Aside from the fact that people
>who are blessed with genes giving them pleasureable orgasms are likely to
>produce children who also have pleasureable orgasms?
That, because female copulatory orgasms often result in the retention of
sperm from males of high developmental stability*, it makes females more
likely to retain sperm which will impart genes giving their offspring a better
shot at survival. That's a mouthful, and I'd be happy to expand in plainer
English, if anybody wants.
Bryant
*Note: you know, "developmental stability" is pretty easy to explain, but
isn't a familiar concept, even to most biologists. I only know about it
because I happened to fall into a job studying it a few years ago. I'd
be happy to clarify the concept, if it's a stumbling block in the
thread--I've just not wanted to unnecessarily invest bandwidth on an
explanation if everybody understood the concept, you know?
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