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Re: Where are the zoologists?
Pat Dooley (patdooley@aol.com)
23 Dec 1994 01:05:06 -0500
Are we having fun yet?
>You treat time as if it is some sort of guiding force. Here is how I see
>your understanding of natural selection and the AAH:
Evolution takes time. It goes faster on small populations and
on islands. It speeds up when there are major environmental changes
going on.
>miocene ape fossils
>
Who knows; lots of ape species, most of which died out, while
monkey species proliferated.
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>[NATURAL SELECTION, WHICH HAS A WILL OF ITS OWN, ACTS SO FAST WE CAN'T
SEE
>IT]
>
Natural selection is a force that acts as fast or slow as the environment
dictates. In the
case of Galapogas finches, the time scale spans mere decades. We could see
the
effect of natural selection if we had a reasonable fossile sequence
covering he crucial period.
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>no fossils at all, but insert aquatic apes that engage in complex,
>specialized activities
Well actually, the behaviour isn't that complicated given the right
environmental
conditions. The rudiments have been observed in other primates.
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>[NATURAL SELECTION KEEPS WORKING HERE, REALLY FAST, ON EVERYTHING BUT THE
>SKELETON, BUT STOPS WORKING JUST IN TIME FOR US TO DISCOVER THE....]
>
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>...Australopithecine fossils! No evidence of aquatic activity at all. Of
>course, they were lousy bipedal apes, so that's why we need to insert...
>
Well, they were not very good runners; they were definitely bipedal
walkers;
and it is very difficult to conjure up a scenario that gets them to a
bipedal
state without violating the principle of non-disadventageous
intermediates.
So far, the AAH does the best job of getting the ape onto his feet
before the savannah or jungle predators kill them off.
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>[NATURAL SELECTION AGAIN! IT SUDDENLY STARTS ACTING ON THE LEGS AND BRAIN
>FOR NO APPARENT REASON, SINCE PAT HAS PROVEN THAT APES ARE NO GOOD ON THE
>SAVANNAH AND BY RIGHTS THIS POOR HOMINID SHOULD BE DEAD! WELL, OKAY MAYBE
>NATURAL SELECTION TOLD THE APE TO STAY IN THE WATER A LITTLE LONGER, BUT
WE
>CAN'T PROVE IT. SO WHAT THE HEY, SOME OF THE PHYSIOLOGICAL CHANGES STICK
>AROUND FOR NO APPARENT REASON. ALL OF WHICH EVENTUALLY LEADS US TO...]
>
The whole ball game is natural selection. Once a species gets stuck with a
new feature
it hangs around until it becomes deleterious.
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>Modern humans.
>
Well no. Lucy followed the aquatic phase; almost literally.She is in the
right
location for a species moving away from a dried up Sea of Afar. There was
another 3.5 million years to go before we get to us.
> Natural selection is not a magic wand you wave when you run across a
>feature you don't understand.
>
>Lucie
I quite agree. But natural selection is a powerful tool, and when it
gives unrelated species similar adaptations, one is entitled to ask
whether
that adaptation arose because of similar selection pressures.
Pat D
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