On Wed, Feb 07, 2007 at 03:12:00PM +1100, Peter Shute wrote:
> wrote on Wednesday, 7 February 2007
> 12:56 PM:
>
> > The divergence in mating signals
> > found between these two taxa seems to have occurred recently
> > and relatively rapidly.
>
> Forgive my ignorance, but how do they know that?
If it's anything like the grasshoppers mentioned in Richard Dawkins'
book "The Ancestor's Tale", the difference in mating signals is
probably most distinct where the two taxa overlap(?) than at the
extremes of their ranges. Once the speciation event occurs (for
whatever reason), there is positive selective pressure to drive
the two species apart (different calls, colours, behaviours or
whatever) to avoid unproductive interbreeding.
As with his other books, I can thoroughly recommend "The Ancestor's
Tale" as a excellent introduction into taxonomy, genetics etc.
--
-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-=-
Paul Taylor Veni, vidi, tici -
I came, I saw, I ticked.
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