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Re: Two new FAQs: Everything You Wanted To Know About Cladistics
Ken Kinman (kinman@hotmail.com) wrote:
<One thing I would like to see on the second one is some mention of homoplasies
(convergences and
especially reversals), and how they can sometimes trick both computers and
people into believing
they are synapomorphies (and thus can negatively affect reliability).>
I'd disagree with the inclusion of "reversals" of character polarity and
expression as a
function or aspect of homoplasy: in a computer analysis, they tend to pull the
taxon backwards, as
it were, and collapse nodes -- they do not make false synapomorphies.
<And on the first one, I would quibble a little with equating "traditional
Reptilia" with
"Reptilia minus Aves". Many traditionalists continue to removed both Aves and
Mammalia from
Reptilia, and leave the traditional paraphyletic synapsids (pelycosaurs and
therapsids) in
Reptilia. This is the way it was traditionally done for much of the 20th
Century, and it is still
often done this way outside of cladistic circles.>
And these fellows are still in academics? *shakes head in wonder* I thought
Romer and Cox got
rid of all that nonsense decades ago? I'm glad to see people are keeping
mammals from Reptilia, it
makes me think something's right with the world ... just a pity I forget
whenever these people
ever included Mammalia in Reptilia since their uses have always opposed each
other in content, but
anyway....
=====
Jaime A. Headden
Aaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhr-gen-ti-na
Where the Wind Comes Sweeping Down the Pampas!!!!