[Taxacom] Usefulness vs. convenience (Protista)

Kenneth Kinman kennethkinman at webtv.net
Sun Dec 19 17:07:24 CST 2010

Hi Kleo, 
        Actually, you would be surprised how many people
still classify Rhodophyta outside of Plantae (but not outside of
"plants", since they are clearly "plants"). One such major website is
that of the University of California Museum of Paleontology. If you
click on the link below, you will see that although they don't actually
use the term Protista on this Eukaryota systematics page, they do have a
bunch of  "protist" groups (including Rhodophyta and others) but with
the four Kingdoms (Animalia, Plantae, Fungi, and Chromista) spelled in
capital letters. And I was VERY happy to see that their Kingdom Plantae
is the same as my Kingdom Metaphyta (land plants, i.e. embryophytes). So
they also exclude the green algae (Chlorophyta) from Kingdom Plantae
(Metaphyta) as well as the Rhodophyta.        
        And if you look at the Kingdom Protista
classification that I posted here a few hours ago, you will see that I
include Glaucophyta, Rhodophyta, and Chlorophyta in a broader plant
clade with the exgroup {{Metaphyta}}. So I do consider them all plants.
If you go broader than that, it gets "iffy" whether other "plants" are
closely related or not. Maybe the haptophytes and cryptophytes are (if
the tree of Minge et al, 2009 is accurate in showing them as sister
group to Glaucophyta). But some other algae (part of "plants" sensu
lato), such as  Chrysophyceae, Phaeophyceae, and Xanthophyceae, are in
Phylum Heterokonta and not part of the plant clade at all.  I was rather
shocked that the Encyclopedia of Life  seems to include Chrysophyceae in
Plantae.  YIKES!!!  I didn't think anybody did that any more.         


P.S. I am obviously one of those skeptics who have long regarded
Chromista as an inconclusive (even doubtful) grouping, even though it
seemed based on cladistically reliable data (including molecular).  Now
after almost 30 years, it finally seems to be falling apart, and having
been raised to Kingdom status, I would also call it inconvenient.  All
those textbooks with Kingdom Chromista will probably have to soon be
rewritten.   And I expect the Three Kingdom classification will
eventually also fall out of favor, when it becomes clear that there is
nothing "archaic" about "Archaebacteria" ("Archaea").  And that is
something Cavalier-Smith and I have always agreed upon, and he thinks
that they evolved even later than I do.  So it is seems odd that he
never adopted the name Metabacteria for them.  Oh well.                               
Kleo wrote: 
     Also, anyone know who is classifying Rhodophyta as other than
plants these days? 

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