Re: Evolution, "adaptation", and what's currently adaptive

Len Piotrowski (
Wed, 11 Sep 1996 20:40:31 GMT

In article <514itj$> (Gerold Firl) writes:

>[snip - Firl attempts to understand another point of view]

>In article <>, (Len Piotrowski) writes:

>|> In article <50ncrt$> (Gerold Firl) writes:

>|> >I say "complete" because it ranges from a very simple ability to sense
>|> >light and dark, with no structural "eye" at all, to the sophistication
>|> >of humans and raptors, who can discriminate thousands of colors and
>|> >extremely fine details, with all the intermediates between.

>|> The "completeness" is merely determined by your implicit classification. You
>|> have no independent notion as to how complete "completeness" is for your
>|> perception of "eyeness." I take note of your distinction between the ' no
>|> structural "eye"' and the "sophisticated" eye; a classificatory hedging for
>|> the sake of "completeness?"

>You're lost in the words, lenny. The gamut of vision systems ranges
>from the simple ability of plants to move their leaves to maximise
>solar gain, to the non-imaging eyespots of unicellular organisms which
>also allow them to orient to light, to lens-less pinhole eyes which
>provide rough imaging, to eyes with lenses which can focus images on a
>retina, to the the eyes of raptors and humans, which are as good as we
>get on this little planet. I don't know what you're going-on about,
>with your talk of "eyeness"; "eyeness" is a non-sequiteur as far as I
>can tell.

This bit of backtracking and obfuscation belabors the point about your
argument concerning classification of the "eye" and it's completeness as
such. I suggest you examine your own propensity for non sequiturs, as well the
meaninglessness of your classification system. Significant in all this is the
zoological garden as evidence of an evolutionary pathway for "eyeness"
contradicted by the new suggestions of independent evolutions of "eyes"
presented below.

>|> Your mapping of history to evolution is not very convincing. Do you seriously
>|> propose that the "eye" stalks of terrestrial gastropods are ancestral to the
>|> human eye? Or for that matter, do you really propose that any of the current
>|> life forms listed in your museum of "evolutionary" progress were actually
>|> ancestral life forms related through direct Mendelian inheritance to coeval
>|> living human beings?

>There you go again, lenny. Yes, that is what I am saying. The eyes of
>vertebrates *are* the direct evolutionary outgrowth of ancestral
>phyla. I recommend you take a look at _five kingdoms_, a wonderful
>book by margulis and schwartz which describes all the phyla of life
>and their probable evolutionary relationships. If I recall correctly,
>vertebrates are thought to have evolved from annelids (worms, that

Now worms have eyes Firl? But before you go to far, I believe your zoological
garden said eyes evolved from plant ancestors with direct lineal relation
traced through plankton, molluscs (I won't forget snails), and finally the
mammalian eye, neh? If you disagree with this than you can understand my
disagreement with you.

>|> >Molluscs do have eyes;

>|> Under your broad "completeness" classification, no doubt any light sensitive
>|> receptor is an "eye" by this definition - including those of plants, eh?

>We've gone over this before, lenny.


>Light sensitive organs or receptors are not necessarily eyes.

You've contradicted your own systematics and justification for completeness.
Thus your argument by zoological garden is worthless as proof of anything.

> Eyes
>evolved from simpler light-sensitive structures, but no plants have

Proof please. Perhaps you've not noticed arguments to the contrary, that eyes,
that is, those complex systems we habitually know as eyes, are not simply
deformations of simpler systems?

>Many different animals and protozoa have eyes however, and it is
>estimated that eyes have independantly evolved something like 8 times
>(if I recall correctly); vertebrate eyes did not evolve from mollusc

This is an internal contradiction to your own zoological garden as model for
the evolutionary pathway of "eyes."

>|> >indeed, it is one of those contingent facts of
>|> >history much beloved by semioticians posing as biologists that the
>|> >mollusc eye has some aspects which are intrinsically superior to
>|> >vertebrate eyes.

>|> ... indeed! Historical contingency of mollusc "eyes" proves they were
>|> ancestral to vertebrate "eyes," eh?

>Lenny, the word "superior" is a different word from the word

I'm quite happy to view your zoological garden model as absolutely worthless
as an evolutionary pathway representing "ancestral" *or* "superior"

>|> >[snip]

>|> "Worth" is another one of those concepts that doesn't help in understanding
>|> the problem. It implies to "them" a judgement upon their own fate. I don't
>|> think that is what you want to say. However, it illustrates a similar problem
>|> with the use of "purpose" as the reason for the development or lack of
>|> development for a function.

>That's like saying that dawkins is all wrong because genes can't be
>selfish, they're just units of base-pairs on a dna molecule; we've
>also gone over why your argument from teleology is null and void.

You're right! I have gone over that. But you've missed the whole point about
agency. And possibly so has Dawkins.

>I realise that it's difficult to picture how the incremental
>accumulation of natural selection and mutation at the level of the
>gene could produce such amazingly complex structures as are seen in
>the natural world, but that's just something you need to think about
>more carefully.

No biggee, Firl. It doesn't take a mental giant to comprehend what you're
trying to say. However, without evidence it's simply unscientific.

>Read some books on evolutionary biology, lenny. It
>really works. You just need to understand the huge spans of time

No one's criticizing evolutionary biology, Firl. The criticism is over the
methods of explanation.

>|> >[snip]

>You still haven't explained just what you mean by the recurring phrase
>"meaningful human interaction". It's not practical? Lets take an

Once again, Firl, an emergent, dialogic and symbolic process of social
relationship. Perhaps I could suggest some readings for you, the same as you
and Bryant are so found of suggesting for everyone else.

>A mother teaches her child to talk, to read, to count; real basic
>stuff, happens all the time, all over the world, it's very meaningful
>and - suprize surprize - it's *practical* too!

You trivialize an important aspect of human behavior. I guess I would try the
same thing if forced to account for teaching, talking, reading, and counting
as functional adaptations. However, in as much as these actions involve
meaningful social interaction, they are free to vary: there is more than one
way to teach, to talk, to read, and to count. What makes one way persistent
over another? Why isn't one way more persistent over all others? If it all has
functional adaptationist purposes designed by nature, how come so many forms
of expression without fitness value? What is the relative fitness differences
between 2 and II and two?

>A mother teaches her cub to stalk, to pounce, to kill - ever watched a
>cat and her kittens? - the separation you draw between humans and
>other animals is absurd.

But not as absurd as your claim that this bit of learned behavior must be
subject to a "stalking, pouncing, and killing craving" selected by nature and
somehow linked to the "teaching craving" likewise selected by nature? Despite
this, the implication you draw between the symbolic interaction of the human
mother and her child with that of a mother cat and her kitten is most
assuredly the greatest absurdity.

>|> >You must hate the ideas of marvin harris. I see you as the
>|> >anti-harris.

>|> No, really, I don't hate Marvin Harris!

>I didn't ask whether you hated *him* - I asked how you felt about his
>ideas. Don't be shy. I don't think you'll hurt his feelings.

I'm not shy, Firl. That was precisely what I meant. To be more explicit for
your tender tastes, I don't hate Marvin Harris' ideas, either. However, I
despise your imputation regarding my level of knowledge.

>|> >Have you heard of marvin harris? What do you think of him?

>|> I liked him. Do I have to then be a cultural materialist?

>That depends.

Oh, that depends! If I liked what I read I must be a cultural materialist?

>In _cows, pigs, wars, and witches_ harris presents very
>convincing arguments in favor of the view that "meaningful human
>behavior" is adaptive and practical. He uses the example of the sacred
>cow in hindu ideology, arguing that this is just as much a practical
>idea as a spiritual one. I would expect you would disagree with that.
>Why are you so coy about it?

Hard to be coy if the question hasn't been raised yet, eh Firl? The expression
in Hindu ideology of this motif, you would agree, is never the same nor fixed
and unchanging. It is, at least in the acculturation example you devised
above, subject to definition and re-definition many times in the lifetime of
the culture. In as much as it emerges in different forms, in different
contexts with different people in different social interactions, the meaning
is a matter of negotiation, hardly dominated by it's purported practicalness
fixated by nature.

>|> >And since humans do function, and they do adapt, how can it be that
>|> >their meaningful behavior is unrelated to their functional
>|> >adaptations?

>|> In it's expressive, non-practical aspect.

>Expressive, non-practical ... art for arts sake, eh?


>All human
>interaction (or only interaction for interactions sake?) is


>You're fooling yourself.

Wasted critique about imaginary hobgoblins!

>|> The "eye" says nothing; the "selection pressures" are not obvious, only
>|> conjectured; "eyespots" on unicellular organisms "show" nothing, let alone
>|> the beginnings of a "process." Your attempt at an explanation just muddles
>|> clear understanding. The proof of a Complete Evolutionary Pathway of the Eye
>|> is merely a kludge of selected living organisms into a rickety framework of
>|> suggested ancestral relationships without any ground truth. Your zoological
>|> garden of serial progress is contradicted by your own admission to independent
>|> processes. Your "explanatory" model truly is a mystery, and, in as much as it
>|> suggests facts outside of contexts, exhibits an expressive design that
>|> confuses relationship.

>Only to someone lacking in comprehension of the processes and
>relationships involved.

You've offered no comprehensive process or relationship for the
representatives occupying your zoological garden!

>Some eyes evolved independantly, others are related by direct lineage.
>You need to trace the branches of the evolutionary tree to see which
>is which. Again, I invite you to do a little research. Try it, you
>might like it.

I have. What little I know begs the question about the evidence for
the exact and scientific processes and relationships you so easily assign to
the particular branches of the evolutionary tree. It is my understanding that
even in your field of expertise, there is some controversy about how
independent this evolution really is. At any rate, your nod to this notion of
independent evolution is another contradiction of your model for a unified and
complete evolutionary pathway to the eye as represented by your zoological

>|> Earlier you complained about me asking too many questions, and now you
>|> admonish me to ask more. Do you really expect me to believe this to be an
>|> sincere request for dialog, Firl?

>That seems pretty far-fetched, at this point, doesn't it? I have made
>a sincere attempt to understand your point of view.

Your sincere attempt is truly hard to believe.



"If you can't remember what mnemonic means, you've got a problem."
- perlstyle