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Re: New finds



A few old answers...

----- Original Message -----
From: "philidor11" <philidor11@snet.net>
Sent: Sunday, July 14, 2002 5:00 PM

> [...]
> Further, it is possible to leave out technical elements, references to
> logics other than everyday verbal logic.  Give you an example:
> Dinogeorge commented:
> <To convert any cladogram into a "linear model," or Hennigian comb as it's
> sometimes called, simply single out
> one lineage to be the spine of the comb and arrange all the other lineages
> as "side branches" of the selected lineage.>
>
> This could be expressed:
> Any single species has one and only one ancestral species at any point in
> its evolutionary history.  A diagram of the evolution of any contemporary
> species will show a straight line with offshoots from the main stem.

Under many (not all) definitions of species a species can have 2 (more or
less closely related) ancestral species at the same point in its
evolutionary history. Speciation by hybridism is common among plants (for
those who agree to call that speciation). In any case, the straight line is
a consequence of presentation that means nothing in reality, and so is the
main stem. :-)