Re: Wynne-Edwards ( was Homosexuality)
- From: Guy Hoelzer <hoelzer@xxxxxxx>
- Date: Tue, 31 Jan 2006 16:24:06 -0500 (EST)
in article drj0kq$1a6m$1@xxxxxxxxxxxxxxxxxxx, John Edser at edser@xxxxxxxxxx
wrote on 1/29/06 10:13 AM:
> Guy Hoelzer hoelzer@xxxxxxx wrote:-
>
>>> PART TWO:-
>>>> I agree that every level of selection, such as the individual
>> organisms, must
>>>> have a phenotype (including the trait of fitness) that is a non-
>> additive
>>>> result of single gene influences.
>
>>> JE:-
>>> Do you agree that "the trait of fitness" as measured at the gene level
>> is
>>> always dependent on another level and is therefore not an independent
>>> fitness?
>
>> No. I have tried to convey to you that I do not see
>> dependence/independence
>> as a black and white issue.
>
> JE:-
> You did _convey_ this. The problem was is it made no sense to me. The reason
> why is this: If you allow "dependence/independence" to be complimentary and
> not contradictory (it cannot be both) it becomes impossible to distinguish
> mono-centricity from poly-centricity.
I disagree. In addition, I don't see the discrete or continuous nature of
dependence/independence as something we get to choose. I see it as an
empirical issue, and IMHO the evidence strongly supports the continuous
view.
> What is even worse than a false
> distinction is no distinction at all allowing ambiguity.
Contrasts need not be black and white to be informative.
[snip]
>
>
>> IMHO, no two things or processes in the
>> universe are 100% absolutely independent.
>
> JE:-
> That may well be. Popper's point was: it matters _not_ if you are right or
> wrong just: can what you and others propose be tested? If so, what
> constitutes a valid test and what should you test firstly has to be answered
> clearly and unambiguously otherwise science is reduced to an opinion which
> is inefficiently tested. Every opinion is as valid as any other. In this
> situation, those with more political clout get to enforce their opinion and
> dictate what nature is.
I disagree. Some hypotheses/models (opinions) are more consistent with the
evidence than are others. If you take an information theoretic approach to
such an analysis (e.g., AIC), you can distinguish between plausible and
implausible models with exquisite sensitivity.
>> The entire universe is connected. IMHO the issue is whether something is
>> sufficiently independent that it takes control through self-organization.
>> When I say that two different levels of biological organization serve as
>> levels of selection, I mean that I think fitnesses at those levels are
>> sufficiently independent.
>
> JE:-
> Unless you define "dependent" to be contradictory to "independent" you can
> explain away anything you prefer without fear of refutation simply because
> no contradiction now exists to challenge it.
I disagree. Virtual refutation is still possible as I described above. I
also see dependence/independence as contradictory even as they can coexist,
as in a push/pull relationship. They coexist in a dynamic tension because
they are contrary to one another. If I am right about nature, then I think
it is incumbent on us to develop a philosophy of science that embraces
natural contradiction, even if this leaves Popper's philosophy in the dust.
IMHO we are well along the way to developing and implementing such a
philosophy, although there is clearly resistance from people like you who
refuse to think outside Popper's box. This is another point on which I
think we should agree to disagree.
>>>> I'm not sure what you mean by the "fitness of a trait" when you so
>>>> emphatically insist that fitness can only be a quality attributable to
>>>> whole organisms.
>
>>> JE:-
>>> Empirically, fitness is indeed just "a quality attributable to whole
>>> organisms". This does not mean that a useful simplified model of fitness
>>> cannot heuristically refer to the fitness of just a single trait. I was
>>> referring to the common gene centric heuristic model of the fitness of a
>>> single trait where I absolutely insist that this model never be misused,
>>> i.e. replace the theory from which it was simplified. The theory the model
>>> was simplified from only attributes a heritable fitness to be a quality
>>> attributable to one fertile organism.
>
>> Thanks for clarifying. I am familiar and comfortable with that abstraction.
>
> JE:-
> But you have not made it perfectly clear what in your opinion distinguishes
> a theory from a model. Unless you can do so you are allowing yourself to
> switch between either at will reducing the argument you were "comfortable
> with" to just ambiguity and subsequent misuse.
>
>> Unfortunately, I have a different problem with the concept of a trait that I
>> find harder to put aside. IMHO, what we call traits are almost always
>> figments of our imagination. In other words, I don't think the traits we
>> usually talk about exist as entities or agents.
>
> JE:-
> I would put that more concisely: a trait is a dependent entity which is just
> a heuristic simplification of nature. Any dependent fitness level is not an
> empirical level of fitness, just a useful heuristic level of fitness that
> has to be assumed in order to tackle the complexity of the problem. The big
> danger is such heuristic assumptions tend to become so familiar to those
> that work with them they fail to distinguish them as such and misuse them.
I agree with your sentiment, but not about the nature of traits. I don't
think that they are simplifications of nature. I see them as false
attributes. I think that most often when we identify a trait it is
analogous to claiming that a rainbow is a real thing. It is easy to imagine
that rainbows and organismal traits are real agents and we are prone to
writing myths about them, like there is a treasure at the end of the
rainbow, as if there is a rainbow to have an end. To further clarify the
contrast between our arguments, I would say that claiming something exists
when it doesn't complexifies nature, rather than simplifying it.
[snip]
>>>>>> While I am glad to see you using the slime mold paper I sent you in your
>>>>>> argument, I am not convinced by the interpretation of results you have
>>>>>> advocated.
>
>>>>> JE:-
>>>>> Ok. How do you explain their results?
>
>>> JE:-
>>> Please provide an answer.
>
>> This thread has gone on so long, and interspersed comments so complicated,
>> that I have lost track of your original claim based on this paper. I'm
>> afraid you will have to repeat it for me to answer.
>
> JE:-
> I claim their results can be explained in the simplest possible way: each
> cell obtained a mutualised but not necessarily equal fitness advantage
> (which is just the mono-centric explanation) which however ALWAYS comes at a
> price (no free lunches). In this case the price was a 1/3 risk that each
> cell forms the stalk wherein it does not reproduce at all. However, taking
> this considerable risk was cheaper per cell than not taking it because spore
> formation with an elevated stalk to distribute the spores from drastically
> reduced the fitness per cell. Cheating was selected against using epistasis
> (as they discovered) only because the cost of cheating exceeded the gains in
> cheating at just a mono-centric cell level (in this case each cell is one
> Darwinian selectee). If the stalk is reduced in height to become just a
> little below the optimum via cheating then all the cells that reproduced,
> which of course included any cheaters, suffered a fitness loss. At some
> point this loss becomes greater than the gains to the cheaters so cheating
> became selected against using the documented epistatic events which enforced
> non cheating.
Thanks for reminding me of your interpretation. It doesn't make sense to me
because the cheaters would have improved their individual fitnesses from
zero to something lower than a 1/3 chance of spore representation. If
selection acted only at the individual level, then the system should
collapse due to the success of such cheaters.
My interpretation is that selection at the level of the slug (the social
group of individual cells) favored the evolution of pleiotropic entanglement
between participation in prestalk and spore development of the slug. As
with the origin of Mendelian segregation rules, this limited the opportunity
for selection at the individual cell level, which can compromise the
function of the slug.
>>>> My point was not about onus at all. It was about logic.
>
>>> JE:-
>>> But it was logic which placed the onus on you because (I repeat) it remains
>>> "pointless and wasteful to explain anything in a way that is more
>>> complicated that it needs to be".
>
>> Then I think the onus is on you, because I am arguing that selection works
>> the same way whenever there is heritability of fitness.
>
> JE:-
> You left out: " ..whenever there is heritability of fitness " at
> multilevels.
I would choose not to include that language because I don't know what a
"multilevel" is. Whatever it might be, my claim does not depend on it, or
on any particular level.
>> You are the one
>> saying there is something different when heritability of fitness exists at
>> levels other than the individual, so your claim is less simple than mine.
>
> JE:-
> I claim that just the one independent level empirically exists so that my
> proposition is: " ..whenever there is heritability of fitness " at just a
> mono-centric level.
So you extend and make less simple my claim, which does not specify anything
about level or levels.
> Since my proposition is much easier to test than yours it is requited to be
> tested firstly as a result of Occam's Razor. Therefore the onus is on you to
> establish why a multi level proposition should be assumed and tested BEFORE
> the Darwinian mono-centric level.
You are free to hold that opinion, but as I said before I don't see any
application of Occam's razor in this way, nor do I find Occam's razor to be
compelling in any context. I explained my position on this before, and
neither you nor the website you cited have swayed me.
Guy
.
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