[ExI] IQ and beauty

[Dan TheBookMan]

On Thu, Oct 8, 2015 at 8:56 PM, John Clark <johnkclark at gmail.com> wrote:
> On Thu, Oct 8, 2015 at 10:29 PM, rex <rex at nosyntax.net> wrote:
>>
>> There are many examples of semi-cyclic population levels, but
extinctions?
>
> There are vastly more examples of extinctions than there are of
> semi-cyclic population levels

You left out some context. Rex wrote:

'But it doesn't follow that this would lead to extinction. After a
positive feedback loop operates for a while it may alter the
environment in such a way that the formerly positive feedback is now
negative. Voila, you have semi-cyclic behavior instead of extinction.
There are many examples of semi-cyclic population levels, but extinctions?'

I believe this and the earlier parts of his post were asking you about
linking actual extinctions to the mechanism -- not merely saying there are
plenty of extinctions. Heck, with many long ago extinctions -- ones guessed
at from the fossil record -- we can't always be sure a species went extinct
in the sense of leaving no descendants or simply formed new species
(whether by anagenesis or cladogenesis).

Now, sure, one can't be sure that there's evidence for 'semi-cyclic
behavior' either, especially going beyond population genetics models and
fields studies today to the fossil record.

Regards,

Dan
  Sample my Kindle books via:
http://www.amazon.com/Dan-Ust/e/B00J6HPX8M/
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