"John Edser"  wrote in message
news:...
> Name And Address Supplied wrote:-
> 
> > > > NAS:-
> > > > .. my point is simply that absolute
> > > > offspring number is not the appropriate maximand.
> > > > The appropriate measure is relative.
>  
> > > JE;-
> > > The maximisation of just a relative fitness
> > > measure remains a logical impossibility unless an
> > > an absolute fitness measure is maximised, firstly.
>  
> > NAS:-
> > That is incorrect. The maximum relative fitness does not necessarily
> > coincide with the maximum absolute fitness, i.e. one evolutionary
> > strategy might maximise one and not the other. To decide which
> > strategy is favoured by natural selection, we need to choose between
> > the relative or absolute fitness maximand. And the relative fitness
> > maximand is the one that delivers the correct answer.
> 
> JE:-
> I will argue that you not correct where
> such a basic difference does allow a test.
> Using such a test, either your view or my
> view must will stand refuted. Do you agree
> that this is the case?
> 

If I understand you correctly, then yes, I agree. And that was exactly
my point (above).

> > > JE:-
> > > The sentence and question
> > > remain rational and unambiguous.
> > >
> > > What do you claim not to understand
> > > now? Is it "mutualisation"? Why does
> > > this simple term remain a mystery
> > > to you when it was dealt with
> > > by Hamilton's rule as any case
> > > of -c?
>  
> > NAS:-
> > "mutualisation" is not a standard term in social
evolution theory. I
> > suppose you are trying to say something about
"mutualism", but clearly
> > you are referring to a process ("-ation" suffix),
whereas "mutualism"
> > is simply a way of describing a matrix of costs and benefits.
> 
> JE:-
> It is nonsense for NAS to suggest that
> "mutualisation is not a standard term" because
> it remains employed (but just soundly ignored!)
> by Hamilton et al within Hamilton's rule.
> This rule attempts to measure
> fitness changes via an _association_ between
> a single actor and recipient/recipients. It
> is IMPOSSIBLE to measure when any association
> can evolve by only measuring _unilateral_ gains,
> i.e. gains/losses to just the actor OR the
> recipient. At all times, the fitness being
> measured by Hamilton et al is _not_ unilateral.
> 
> ___________________________________________
> Definition:
> Mutualisation within Hamilton's rule is the
> process whereby both the recipient and the
> actor make a fitness gain.
> ___________________________________________
> 
> For this gain to be REAL it has to be
> a measured ABSOLUTE gain, i.e. the
> gain must constitute a total of
> some kind that allows a net result
> and not just a gross result,
> to be calculated. Do you agree?
> 

You could have spared yourself such a long answer if you had only just
read what I had written. I am well aware of what "mutualism" is. I was
merely confused by the strange term "mutualisation" - again, see
above.

> > > JE:-
> > > Surely you know what this evolved
> > > game theory strategy was? It reduced
> > > risk and hence mutually increases
> > > (but not necessarily equally
> > > increases) fitness.
>  
> > NAS:-
> > John, you'd save alot of your time and mine if you just got to the
> > point, say what you have to say, rather than have me guessing.
> 
> JE:-
> You brought this up and not me.
> Hamilton et al deal in the evolution
> of fitness _associations_.
> Any association is a form of co-operation
> where this may provide negative or positive
> outcomes for those involved.
> 
> _____________________________________________
> Co-operation within and between species
> has generated only _one_ Evolutionary Stable
> Strategy. Please tell sbe reader's  what
> you think it is.
> _____________________________________________
> 

John, we were talking about Hawks and Doves, not mutualisms. 

> 
> > > > > JE;-
> > > > > However, the above is just a simplified_model_. Such
> > > > > a model does _not_ constitute a documented observation
> > > > > of nature and therefore cannot replace such
> > > > > a documented example. The only valid usage of such a
> > > > > model is to help prepare a biological experiment
> > > > > to test the theory the model was derived
> > > > > from via the process of modelling simplification.
>  
> > > > NAS:-
> > > > The model provides a hypothetical counter example to
your claim. There
> > > > is no theoretical reason why the model behaviour could
not be played
> > > > out in nature. So there is no theoretical basis to your claim.
>  
> > > JE:-
> > > A "hypothetical counter example" to my "claim"?
> > > From what I have read you do not demonstrate
> > > any understanding of what my claim actually is.
> > > To remove any confusion please write or quote what
> > > you understand my claim to be.
>  
> > NAS:-
> > Essentially, that absolute offspring number is the appropriate
> > maximand. I disagree.
> 
> JE:-
> So there is no confusion, this absolute assumption is
> defined as the total number of fertile forms reproduced
> into one population by each parent, i.e. it is represented
> by a testable numerical total that once created remains fixed
> for  all time within biological history.
> 
> To avoid confusion, please explain what your
> "hypothetical counter example" was and how
> it differed to my claim.
> 

Stemming from our discussion about the appropriate maximand was your
claim that natural selection could not cause a population to move
towards extinction. I provided the example of the Hawk invading the
healthy Dove population. A population of Hawks is much worse off than
a population of Doves.
It clearly shows that the Hawk strategy can, through natural
selection, jeopardise the health of the population. Only relative
fitness matters - the Hawk is relatively fitter than the Dove in a
population with a mixture of the two, even if the Hawk in a population
of mostly Hawks is absolutely less fit than the Dove in a population
of mostly Doves.
 
> 
> > > > > > > JE:-
> > > > > > > Note that just a relative fitness comparison
> > > > > > > can still produce evolution via natural selection
> > > > > > > even as a population keeps on shrinking.
> > > > > > > Unless this relative fitness
(comparison) selection
> > > > > > > can keep up (at least make up the
consistent absolute
> > > > > > > loss) the population must move to extinction. The
> > > > > > > logic is very simple. It is not possible
for an absolute
> > > > > > > fitness _reduction_ to be selected _for_
but it is entirely
> > > > > > > possible for every member of one
population to fail
> > > > > > > to adapt quickly enough even under
intense selective
> > > > > > > pressure. Nature is not perfect so she
cannot always
> > > > > > > produce adaptations quickly enough under intense
> > > > > > > selective pressure, producing extinction.
>  
> > NAS:-
> > This is nonsense. What if the population size is not wholly influenced
> > by the trait in question? What if the population is only momentarily
> > decreasing in size, and will later start increasing again?
> 
> JE:-
> You do not understand the implications of
> an absolute fitness (as defined above).
> 
> The fitness of traits coded by genomic genes are
> epistatic to just _one_ fitness level within
> this theory. Do you know what this proposed single
> level of fitness is? AFAICS you incorrectly thought I
> was only supplying  an over simplified MODEL. Such a
> model would be utterly misused if it suggested
> that at all times, within nature, the population
> size "is wholly influenced by the trait in question".

It is a simple model, but it does provide a counter to your claims.

> 
> >snip<
>  
> > > > > JE:-
> > > > > I have not "neglected the possibility of
> > > > > frequency dependent selection", I suggest
> > > > > it evolves to a point of fitness mutualisation.
> > > > > Predator and their prey populations _can_ reach
> > > > > a point of fitness mutualisation which can
> > > > > evolve to become more and more efficient.
> > > > > Here Van Valen's Red Queen war is replaced
> > > > > by fitness mutualisation because it is more
> > > > > effective and a lot cheaper for all concerned.
> > > > > Only here can the absolute Darwinian fitness
> > > > > of ALL increase without the massive
> > > > > investment required by spiralling
> > > > > offence/defence costs that Van Valen's
> > > > > logic requires.
>  
> > > > NAS:-
> > > > Your sudden switch to interspecific interactions is somewhat
> > > > confusing.
>  
> > > JE:-
> > > Why is that? Prey/Prey, Prey/Predator and
> > > Predator/Predator fitness relationships
> > > must all evolve together in the real world.
>  
> > NAS:-
> > Indeed, but we were discussing an intraspecific example, an example
> > which I had proposed to illustrate a flaw in your reasoning.
> 
> JE:-
> For Darwinian theory where species are not
> a valid absolute assumption, it makes
> little difference because the logic remains
> the same. So there is no confusion, please
> quote or restate what my reasoning was
> and then present your intraspecific example
> that lllustrates "a flaw" in that reasoning.
> 

I'm struggling to see what logic was behind your claim that natural
selection could not push a population towards extinction, by reducing
its absolute fitness, but that is precisely what you stated, and that
is what the Hawk-Dove game disproves by counter example.

> > > > > JE:-
> > > > > I find it amazing that you freely admit that
> > > > > "an absolute fitness that is testable should be
> > > > > identified within Neo Darwinism", yet you
> > > > > flatly decline to attempt to provide one! You
> > > > > just end up withdrawing into a WW1 trench
> > > > > by suggesting that "for a broad class of
> > > > > situations, relative fitness suffices".
>  
> > > > NAS:-
> > > > Apologies, I made a mistake. I mis-read "absolute
fitness" for
> > > > "general measure of fitness" or something
equivalent. So I do not
> > > > agree with your point 1.
>  
> > > JE:-
> > > So, what now is the _point_ of this discussion?
>  
> > NAS:-
> > The appropriate maximand.
> 
> JE:-
> Please provide an unambiguous
> definition of it.

My position is that yours is incorrect, not that I know exactly what
the correct maximand is.

> 
> > > > > JE:-
> > > > > Logically, it remains untrue that "for a
> > > > > broad class of situations, relative fitness suffices".
> > > > > Unless a defined 3rd fixed point of reference exists,
> > > > > just measuring a relative difference means nothing.
>  
> > > > NAS:-
> > > > The question should provide the appropriate reference point.
> > >
> > > JE:-
> > > Yes it should but it doesn't, does it.
> > > Please provide an example.
>  
> > NAS:-
> > The reference is provided by the question. Contrast "how does an
> > allele's frequency change in a population" with "how
does a species
> > abundance change in a community". The key references are
"population"
> > and "community" respectively. An allele might increase
even though it
> > causes an absolute decline in population size - but if we are
> > answering the first of the two questions, we do not care about the
> > decline of the population size, since the allele's frequency is
> > measured within the population.
> 
> JE:-
> You have failed to distinguish between just a simplified
> model and the theory it was simplified from. This provides
> a real danger that you may allow just an over simplified
> model to invalidly  compete and win against the theory
> from which is was simplified/over simplified which I am
> sure you would agree would be an absurdity.
> 
> How an allele's frequency changes in a population
> and how a species abundance changes in a community
> can only be explained using a testable theory. Please
> provide or just acknowledge, such a theory.
> 

MOre on this later . . . I have to run.
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