Re: AAT Theory
H. M. Hubey (hubey@pegasus.montclair.edu)
10 Oct 1995 04:23:11 -0400
Phil Hunt <philip@storcomp.demon.co.uk> writes:
>> Well, the sex selection seems to be a standard dumping ground like
>> money to explain things for which we can't find any other explanation.
>The fact that sex selection is a convenient explanation for a
>characteristic, doesn't mean it is the wrong explanation.
The problem is not that it's the wrong explanation; it's no
explanation because its explanatory value is zero. It's like
saying that rocks know how to fall down. The real question is why
would female humanoids find no fur sexy when it was fine with
them when they their fur.
It's like creating God for an explanation by arguing that the
universe could not have created itself and must have a maker.
Well, then doesn't maker need a maker? Following the same
logic we need another God to create the first God and so on.
In the case of sexual selection, there's no causality. It says
that we cannot find any reasons for the changes but the females/males
must have found it sexy otherwise there would have been no mating.
>If there are no other explanations than sex selection, that is likely
>to be the truth. Why else would peacocks have fancy tails?
I don't know about the fanciness but low intelligence animals
might have small capacity to visualize objects in three dimensions.
The big tail could have made the bird look bigger than it is
at least to some predators and the designs might have made the
tail look like the head/face of a bigger animal. As for the colors
who knows? Either it would have been plain or had a design. No matter
what kind of design it has we could always ask the same question
about the design; Why this particular one?
>> I don't see any way to prove or disprove sex selection changes for
>> anything in general.
>ago. Humans are largely hairless, and many of the places where they
>have hair have a sexual significance. The fact that men have more facial
>hair than women cannot IMO be explained by anything other than sex
>selection. It seems to me reasonable that other aspects of human hair
>(and lack of it) might also be explained by sex selection.
Some peoples (Orientals) have less facial hair. Does this mean that
their female ancestors had different tastes ?
In recent times, we can see for sure that the American Indians had
different tastes (maybe even Asians around the time of Ibn Batuta)
since they used to pull out their facial hair.
>> As for the keeping cool, it would mean that they had to somehow
>> become more active than the apes from which they split.
>Not necessarily. Erectus, being bigger, had a lower S/V ratio than
>habilis.
But this also works in the other direction. If by being bigger
they were going to have problems with heat expulsion why would
they get bigger and then lose their hair. IF there was no
reason for them to lose their hair then it wasn't hot enough
to cause it. And if it was hot, they could have just as easily
become smaller and expel heat more readily. Why get larger and
then lose hair? Was it cold making them larger and then all
of a sudden get hot? Even then, why wouldn't the selection
work to make the smaller ones survive instead of making them
lose their fur?
>Forests have more shade than savannas, so a move out of forests
>would require more ability to keep cool.
Dry air causes problems with the skin burning and not with
heat expulsion. I find it extremely uncomfortable in moist
heat but not dry heat. In contrast in dry weather the sun
beating down is a killer. This would mean that they should
have kept their fur as defense against the rays of the sun.
And their heat expulsion would/could have been made easier
as in dry weather these days for humans.
But then the savannah animals would be losing their hair too
but the ones who lost them seem to be associated with water.
>No. Predators wouldn't be much of a problem to a group of hominids with
>weapons. Humans are slower than lions anyway, so running away wouldn't
>work.
But this happens much later. By this time they intelligent
enough (probably) to be able to use tools effectively and even
speak and make plans to hold off the predators.
>Although humans can't run fast, they can travel long distances and can
>follow prey until the prey is exhausted.
CAn they tire out gazelles, deer, bison, horses....? It's possible
that the domesticated animals like cattle and sheep might be
slow, cumbersome and lacking endurance perhaps because they were
bred that way but how about wild ones? Has anyone measured their
endurance? I don't mean running at top speed either.
I don't even know how one would go about trying to measure
"endurance"? Every animal will break down if pushed near its
capacity/limit for a length of time.
--
Regards, Mark
http://www.smns.montclair.edu/~hubey
|