Tim Tyler  wrote:-

> > > In my essay I suggest three factors that have been rather neglected
> > > by group selection's critics that may assist group
> > > selection's operation:
> > >
> > > * Habitat-specific selection;
> > > * Xenophobia;
> > > * Divergent selection;
> > >
> > > http://alife.co.uk/essays/reviving_group_selection/

> > JM:-
> > And I continue to doubt that any of these things has anything to do with
> > group selection, pro-or-con.  Group selection and spatial
> > variation resulting
> > from viscosity and individual selection are completely different things.
> > Variation between groups caused by individual selection does not provide
> > any kind of raw material for the operation of group selection -
> > at least if
> > you accept G. C. Williams' "parsimony" principle.

> TT:-
> In case I have not made this abundantly clear in the past (in my
> discussions with John Wilkins) I most certainly do not accept
> G.C. Williams "parsimony" principle.
> I assume this is a reference to the bit in "Adaptation and Natural
> Selection" where Williams gives the examples of a deer outrunning a bear.
> Williams says a slow herd of deer will become extinct, while faster ones
> will survive.
> He distinguishes between an adaptive herd of deer and a herd of
> adaptive deer - and that this is thus an example of individual
> selection - and not group selection - on the grounds that in
> science one generally prefers explanations on the lowest possible
> level.
> I disagree completely.  Group selection is (or at least should be!)
> differential reproductive success of groups on the basis of group
> traits.  Consititing of fleet deer /is/ a trait of a herd of deer.

JE:
No, the trait "fleet deer" is a mutualised
trait. This means that the Darwinian fitness as
I have defined it (please refer to "A DECLARATION
OF MEANING") increases for _every_ member of
a _group_ that has the trait "fleet deer" but
not necessarily equally.

The gain on the ground (as against the Darwinian
fitness gain) is just a reduction of risk. The logic
is exactly the same as an insurance company. You
pay a premium (the cost of being fleet) where the
gains for the premium holder are larger than
the premium cost so you end up
making a profit. The fleet deer trait as a
cost provides a higher Darwinian fitness return
to each adult (fertile form) when grouped than when
not grouped. This is not selection _for_ the group
it is selection _by_ the group, i.e. the group is
not a selectee it is a selector: its exact causative
opposite. The mutualised effect (mutualised: an
absolute fitness gain for all group members and not
just a gain in relative fitness) of this gain will
evolve an optimised group size for however, individual
gain, i.e. a group where the Darwinian
fitness for each becomes maximised but not
necessarily equally.  If the group
expands in size beyond this point then this
reduced maximand is selected against at the individual
level. In the field you will observe individuals
being expelled from oversized groups via aggression.
Also, the evolved optimised group size may become
learnt.

V.C. Wynne-Edwards last book changed his focus of
group selection from selection for the group to
selection by the group, i.e. he entirely dumped
his original thesis as to what group selection
was because cause and effect was now
reversed. Selection by the group via selection on
Darwinian individuals only produces an additive grouped
fitness, i.e. a fitness whereby the each Darwinian
individual remains entirely fitness INDEPENDENT.
Because Neo Darwinians do not understand what
Darwinian fitness is (and they refuse to
be persuaded that this is indeed the case) they
confuse group selection with mutualised individual
selection all the time. Also, the misuse of Hamilton's
rule to measure when a supposed altruistic trait can
spread has confused identifying mutualised fitness
almost completely. Unless _real_ objective (countable)
fitness  maximands are proposed (not just statistical
reworks), compared and testable to refutation the Neo
Darwinian focus on just relative fitness results leads
nowhere.


I would be grateful to anybody who can provide
me with the title of Wynne-Edwards last book
since I have mislaid my copy of it.




Regards,

John Edser
Independent Researcher

PO Box 266
Church Pt
NSW 2105
Australia

edser{at}tpg.com.au









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