Re: Metamorphosis - plausible evolutionary scenario?
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Re: Metamorphosis - plausible evolutionary scenario?         

Group: sci.bio.evolution · Group Profile
Author: John W Edser
Date: Nov 19, 2007 22:35

pineapple.link@yahoo.com wrote:-
> Bottom line - currently we have something that goes through these
> three stages (more if you count the egg, but I'm not interested in the
> egg at this point): 1) caterpillar, 2) death/liquefaction, 3)
> butterfly. I have asked to assume that, in the past, there were only
> the first two stages (caterpillar, death/liquefaction), and we want to
> somehow add the third - butterfly. How can we get there with a
> plausible evolution/selection scenario? I pointed out that it would
> seem to be difficult to evolve anything past the death/liquefaction
> phase, as it is hard to see how further changes in this liquefaction
> phase could be selected for/against. Note that I am assuming
> evolution by small steps, as Darwin envisioned it.
>snip<
> There also seems to be the problem that this critter is not even
> fertile until it hits the butterfly stage. So, if indeed in the past
> there were simply the first two stages (caterpillar, death/
> liquefaction), this caterpillar must have had the ability to reproduce
> itself, which was then lost but regained in the butterfly?

JE;-
Firstly, you have to grasp the _amazing significance_ of the single,
Darwinian empirical cycle of reproduction: fertile adult --> fertile adult,
i.e. not fertilised egg --> fertile adult _or anything else_. Given just
the ONE, VALID, EMPIRICAL Darwinian reproductive cycle of nature within
evolutionary theory, anything that happens in-between including
metamorphosis or the death of one entire infertile organism can only
represent a part of one fertile parental form. Therefor any infertile
developmental stage _remains at all times_ under the control of at least,
one fertile body fitness.

A possible scenario: The developmental caterpillar stage, which represents
one part of one Darwinian biological whole is always controlled either
directly or indirectly by at least one fertile form fitness. If we
hypothesise that the original cycle was FERTILE caterpillar --> FERTILE
caterpillar (which is not necessarily the case today) then changes to the
fertile parental grub such as the evolution of gliders (which may have
evolved into wings later on) is obviously passed on via the one Darwinian
cycle. Selection can now alter WHEN these wings etc appear. If the adult
form becomes specialised in distribution and mating and the grub in mostly
just eating to obtain sufficient nutrient to complete one Darwinian cycle
then selection on just the fertile stage can suppress wing development etc
to only emerge within a newly evolved chrysalis stage allowing two
specialised but entirely fitness DEPENDENT forms to evolve under the
direction of just the one, same, fertile body fitness allowing them to
appear as we view them today.

Outline for the evolution of the one Darwinian cycle:-

1) Simple fertile grub --> simple fertile grub

2) More complex fertile grub --> simple infertile grub --> more complex
fertile grub.

3) Very complex fully winged etc fertile grub for mating and
distribution---> more simple infertile grub with a new chrysalis.stage so
the wings etc do not have to be carried by a specialised feeding phase where
they would be a hindrance---> Very complex fully winged etc fertile grub for
mating and distribution.

If you view the Darwinian cycle incorrectly, e.g. simple infertile grub with
a chrysalis.stage ---> very complex fully winged fertile grub --> simple
infertile grub with a chrysalis.stage , you get entirely the wrong
perspective! I may add that this quite incorrect perspective of the one
Darwinian cycle has been consistently provided by mathematicians who allow
themselves the luxury to start and end the one empirical falsifiable
Darwinian cycle anywhere they choose as a modelling OVER SIMPLIFICATION. It
should be apparent that this has allowed a reversal of Darwinian cause and
effect within testable evolutionary theory _ misrepresenting evolutionary
science_.

Regards,

John Edser
Independent Researcher

edser@ozemail.com.au
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