Re: Refs, please... was... Re: AAT Theory

H. M. Hubey (hubey@pegasus.montclair.edu)
20 Oct 1995 17:33:56 -0400

David Froehlich <eohippus@moe.cc.utexas.edu> writes:

>MSS/SSS (let us call them scenarios to be completely honest and
>evenhanded) argue that since the last common ancestor lived in a
>terrestrial forest/savannah/mosaic environment and the fossils we do have
>are in a terrestrial/savannah/mosaic environment that the transition most
>likely occured in a terrestrial/savannah/mosaic environment.

Ok. let's call them scenarios.

Both MSS/SSS posit an environment change. it seems that what
you are doing now is merging the forest, the grasslands and
the "mosaic" (whatever it means by now) and creating a mess.
If nothing changed, then there'd be no niche to fill. There'd
be no split. At least the original SSS posits that the change
was from forest-dwelling to savannah/steppe/grasslands-dwelling.

Now you've put the grasslands/savannah/steppe and the forest
together (and presumably are willing to add water like lakes,
riverine environments and maybe even a sea shore) to creat
a "mosaic".

but in order to create a change of environment/niche you still
have to have the critters move from their previous niches to the
new niche whatever it was.

AAS is the
>scenario that envisions a completely new environment. Which scenario
>requires the most number of environmental transitions (MSS/SSS has 1)(AAS
>has at least 2)?

AAS requires a water environment to the degree that some time
must have been spent in it or around it. My version does't
require that it be a sandy beach with no forests nearby or that
they lived exclusively off fish and shellfish. It could have been
a swamp with trees around the shore and a sea nearby.

MSS/SSS requires less naturally. AT one simplified extreme it
requires 1 transition --- forest to grasslands. At the more
allegedly sophisticated level (i.e. the MSS) then it seems to
require even less i.e. it may require too few to create a niche
and for evolutionary laws to operate.

It's at this point that we can ask the question of why the
others didn't all become bipedal if there was really no
change in the environment.

We can never know the truth, however, we can apply a
>simple rule, parsimony (the simplest explanation that fits the
>observations is the one to be preffered). We may argue about whether or
>not AAS/MSS/SSS fit the observations (I argue that AAS doesn't fit the
>observations), but all things being equal, AAS is unparsimonious.

simple parsimony would work if both produced equally valid
explanations and this is the view propounded by SSS/MSS. But
I don't see them equal. There's a pattern among the animals
that seem to have prediliction/affinity for/with water. I posted
it separately. This is not a binary/bivalent valued problem and
if the level of rigor that is expected from AAS is applied to
the SSS/MSS it too fails. Even more there are other everyday
pronouncements found in books that start to look flaky i.e.

1) surface/area: i.e. Africans (say Kenyans) are allegedly tall and thin
because of this effect. Ditto for the short and squat Eskimos.
Well the pygmies are short, and the northern Chinese are tall.
What happened to the wonderful scientific predictions of the
allometric equations?

2) hair and cold: Africans may have sweat glands in the stomach and
back. Great, they are adapted to hot lands. The Europoids also
have them. OK,so they didn't go too far north. How about Mongoloids?
No sweat glands! So they must be the original cold-landers! Then
how come Europids are hairy (and even North Africans) but not
the Mongoloids/Orientals?

3) Elephants and hippos are allegedly naked because they are large.
This could be putting things backwards. Marine animals are the
largest mammals because the water helps them support their weight
(i.e. whales). So then it must be going into the water that has
enabled elephants and hippos to get large instead of the reasoning
that they lost their hair because they became large. How could they
become large instead of dying off from overheating? They must
have been using the water to cool off (and as a side effect became
large and lost their hair). It's strange that hippos, elephants
and rhinos are hairless AND LARGE. Well, we are large too and
hairless.

-- 

Regards, Mark
http://www.smns.montclair.edu/~hubey