Re: Reproductive Selection

Treus wrote:

_Arthur wrote:

On Dec 15, 9:56 pm, Treus <treusd...@xxxxxxxxx> wrote:

_Arthur wrote:

Treus, how do you suggest that the Asian Elephant (Elephas maximus )
population maintain reproductive compatibility with the African
Elephant(Loxodonta africana) populations ? They are separated by a
great distance, numerous mountain ranges, deserts and bodies of water.

" The pressure of reproductive selection tends to maintain the status
quo of reproductive compatibility (RC) within either population"

That a population of the same species by and large keeps a
reproductive compatibility within itself is well established.


independently all the way back to their common ancestor.

No, You're dead wrong, Treus. There is no pressure at all to be
compatible with dead generations, with "ancestors".


Of course not. The pressure is to be compatible with your own
generation. For S1 to adopt the RC characteristics S2 (a necessary
condition of S1 evolving into S2) goes against the tendency of
reproductive selection pressure. S1 will, as far as reproductive
selection is concerned, always remain compatible with itself, and
therefore never produce an S2 with which it (S1) is incompatible. Or
at least such a development won't happen according to reproductive
selection.


Note this does not mean they can't become incompatible despite
reproductive selection pressure. What it does mean is that whatever
new RC evolves in either population cannot be the result of
reproductive selection.

So one species can split into two species, provided it splits into two
isolated populations first,
Now we're making progress. Not that this contradicts your previous
thread.


I'm not saying speciation can't happen. I'm saying for S1 to evolve RC
with S2 (a necessary condition of S1 evolving into S2), it must do so
contrary to reproductive selection pressure.

Not true. Do you remember the 2-allele case? A population evolves
reproductive incompatibility without ever experiencing any
incompatibility between generations, and thus never going contrary to
reproductive selection pressure.

Note: The thread significantly differs from my previous thread on a
similar topic.

Progress. But even this is not quite correct.

So, what could account for the RC present in a new species, given that
it's not the selection that acts on the post-mating capacity to
generate offspring?

Beats me.

Let me know when you think of something, because until then you got
evolution without natural selection. Maybe it happens by magic.

Why, even if you were correct about all this, would that make evolution
without natural selection? And isn't evolution without natural selection
just drift, whose existence is well-attested?

.

Relevant Pages

  • Re: Reproductive Selection
    ... population maintain reproductive compatibility with the African ... The pressure of reproductive selection tends to maintain the status ... Do mean what could account for reproductive *incompatibility*? ...
    (talk.origins)
  • Re: Reproductive Selection
    ... population maintain reproductive compatibility with the African ... " The pressure of reproductive selection tends to maintain the status ... quo of reproductive compatibility within either population" ... reproductive selection pressure. ...
    (talk.origins)
  • Re: Reproductive Selection
    ... population maintain reproductive compatibility with the African ... The pressure of reproductive selection tends to maintain the status ... reproductive selection pressure. ...
    (talk.origins)
  • Re: Reproductive Selection
    ... population maintain reproductive compatibility with the African ... The pressure of reproductive selection tends to maintain the status ... My explanation for incompatibility is that it's a byproduct ...
    (talk.origins)
  • Re: Reproductive Selection
    ... population maintain reproductive compatibility with the African ... The pressure of reproductive selection tends to maintain the status ... My explanation for incompatibility is that it's a byproduct ...
    (talk.origins)