[Taxacom] More precise sound bite
jcclark-lists at earthlink.net
Sat Mar 28 09:54:37 CDT 2009
On 2009-03-28 00:45, Mike Dallwitz wrote:
> Does this mean that belonging to a paraphyletic group such as reptiles
> usually has less predictive value than belonging to any of the monophyletic
> groups to which reptiles belong?
Knowing that an organism belongs to a paraphyletic group tells you its
plesiomorphies. Knowing that it belongs to a monophyletic group tells
you its apomorphies. Knowing that it belongs to a group in a
classification that includes both paraphyletic and monophyletic groups,
but not knowing which are paraphyletic and which are monophyletic, tells
P.S. Yes, Ken, I remember your markers, but afaict you are the only
person who uses them.
P.P.S. An interesting thought experiment: Could we have a classification
formed of only paraphyletic groups? At first that seems absurd, but
remember that the apomorphies of a clade are also plesiomorphies with
respect to hypothetical derivative clades not yet evolved. In a sense, a
lot of the grade-organized early evolutionary classifications were this,
without the terminological trappings.
Curtis Clark http://www.csupomona.edu/~jcclark/
Director, I&IT Web Development +1 909 979 6371
University Web Coordinator, Cal Poly Pomona
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