Re: Is the AAH a legitimate hypothesis? Of course it is.

From: Paul Crowley (slkwuoiutiuytciuyik_at_slkjlskjoioue.com)
Date: 01/15/05 

Date: Sat, 15 Jan 2005 16:17:02 -0000

"Algis Kuliukas" <algis@RiverApes.com> wrote in message
news:1105757550.786329.209770@c13g2000cwb.googlegroups.com...

> > (d) had to spend most of the day in the open . . ?

> Fair point. (except d - they'd clearly find shelter as much as
> possible, as do almost all equatorial animals)

Most equatorial animals are (a) mammals, and
(b) nocturnal, so the problem does not arise
for them. Primates are (almost necessarily)
diurnal, but they usually get good shelter
from the dense forests in which they live.
As a primate that does not stick to trees all
the time, humans need a dark skin when in
the tropics.

> > > then why
> > > is it so difficult to consider that moving through water more, for
> at
> > > least 2My (since Homo), could have had similar effects
> >
> > You have an amazing absence of any feeling
> > for the processes of selection IF the skin-
> > colour thing (for example) does not operate
> > within around 10 Kyr (400 generations) then
> > it is NEVER going to operate. A period of
> > 100 Kyr is quite unnecessary and to think that
> > an extra 2 Myr would make any difference is
> > beyond the absurd.
>
> You might be right but I don't see how this contradicts my point
> against Jason. If anything it amplifies it.

Your entire notion of 'selective adaptation'
is based on some weird notion that it works
slowly -- over millions of years.

> > There is no such thing as a SLIGHT selective
> > pressure.
>
> It's another relative term. Surely you would accept that some selection
> is stronger than others, right? Some things are neutral with regard to
> selection too? There must be a continuum from neutral to 'very strong',
> therefore some selection might be described as 'slight'.

No. You work under a total misconception.
It's like saying that there can be 'slight
black holes'.

> > > - hair loss and
> > > increased sc fat? It sounds to me like special pleading.
> >
> > It's simple plain commonsense. An analogy
> > I gave to you before was to think of any
> > significant characteristic of a species as being
> > governed by a powerful tide pulling it one way
> > with very strong winds pushing it in the
> > opposite direction -- so it stays in much the
> > same place. Only this happens in about 100
> > dimensions at the same time. If one population
> > spends a small amount of time doing something
> > else, then that activity will have no effect on
> > any characteristic. It CAN'T have any effect.
>
> But hold on, I though you said selection couldn't be slight. Now you
> seem to be saying something more, something quite unbelievable. Not
> only is selection not slight but there are 100 dimensions of 'not
> slight' selection happening at the same time... and... they're all
> exactly equal and oppposite so that the result is... nil, so that "it
> CAN'T have any effect'.

Yep, you're getting the idea. Take a look at
any species you see around. That spider up
on the ceiling, or the tiny mite in your finger-
nails, or the bird you can hear outside. None
have changed in the last 10 million or so
generations. What 'selection' has been in
operation? That is the STANDARD situation
-- not some world of constant fluidity that you
vaguely conceive.

> > > If species A is a terrestrial/arboreal generalist and
> > > species B is a terrestrial/arboreal/aquatic generalist,
> > > I think it's reasonable that species B would have
> > > some traits which help its greater aquaticism.
> >
> > It would be possible to find tens of thousands
> > of species which would prove this false. Many
> > bears (and other carnivores . . such as the
> > jaguar and some small cats) swim and fish a lot.
> > Many don't. There are no obvious differences
> > in morphology between the species that do and
> > those that don't.
>
> What do you mean 'obvious' - another subjective term.
> The fact that some species of bears do and some don't must be reflected
> in their morphology somehow.

NO. Completely false. And you will be able
to present no evidence at all to support
your theory.

> > In any case, it misses the point. If the AAT
> > does not explain bipedalism, then it is a waste
> > of time. I have no idea which features you
> > think your wading theory does explain, but
> > some 'slight' influence will not explain the
> > adoption of a entirely new form of locomotion,
> > and all the morphological adaptations it
> > required.
>
> I think it does explain bipedalism. What did you think I've been
> arguing for for the last seven years? But there is no 'slight'
> selection, remmeber?

How can bipedalism be the result of 'slight
selection'? (Your incomprehension of
matters biological is so far off the scale
as to be beyond my grasp.)

> > > > Let's not confuse the process of speciation and
> > > > adaptive divergence that occurs *after* speciation.
> > > > You need to be clear that one is not the other, not
> > > > by a long shot.
> >
> > Jason's bull*** doesn't help.
>
> > To what other speciation can this be applied?
> > We need analogies where the parent species
> > stayed much the same, but the daughter species
> > developed sets of extraordinary morphological
> > adaptations.
>
> > There aren't any, of course -- not within the
> > whole bird, mammalian, and reptilian orders
> > within the past 60+ million years.
>
> You sure? How could we tell if there were?

Err . . there are all the living species.
There are the fossils. The fact that you
have to ask shows that you have not
even noticed the fact. It's as though
you had an elephant in your house, but
somehow had not noticed its presence.

> > > > Speciation is more likely a product of
> > > > drift and isolation
> >
> > No. It's not. Not THIS truly extraordinary
> > speciation, in any event.
>
> So what's your explanation, Paul?

I have stated it here, often enough.

> > > As I've said before, I'm very happy to be on the
> > > adaptationist's side of the argument here, Jason.
> > > The AAH, in my understanding of it, is
> > > unashamedly neoDarwinist.
> >
> > If only. You first have to grasp what 'selection'
> > means. The fact that you think it can operate
> > _in_one_direction_ over 2 Myr shows that
> > you haven't the beginnings of a clue.
>
> I'm not suggetsing that it was *contantly* and *only* in one direction
> for such a long period but that, as tides come and go but sea levels
> gradually rise and fall, so the level of adaptaion to
> wading/swimming/diving went through many cycles too -

Your grasp of your own arguments is so weak
that you forget them from one paragraph to the
next. The whole basis of you wading theory is
that a _slight_ selection_ pressure over a VERY
long time and operating_in_one_direction_
over all that period produced bipedalism.

> but *overall*,
> since the LCA our ancestors have had greater selection there than chimp
> ancestors. It obviously was the case, because humans swim better than
> chimps. What other explanation could there be?

You've been given it around 6,297 times
in this very forum. (When hominids
stopped being chimps they had to
become as 'aquatic' as every other
terrestrial species.)

Why do you find it so hard to remember
this? Is it difficult to understand?

Paul.