[Taxacom] Paraphyletic groups as natural units of biological classification

Stephen Thorpe stephen_thorpe at yahoo.co.nz
Thu Oct 2 18:00:24 CDT 2014


John,

>My view is that there is no problem of Linnean classification if it is limited to being applied to monophyletic groups<

I think you may have possibly missed the point. If P= MM minus M is paraphyletic, then, in order to have a Linnean classification which recognises M, you also need to recognise P (or else elevate all the species in P to the same rank as M). This is the problem!

> If one wants to apply a name or label to a paraphyletic assemblage then there is nothing to prevent that usage, only with the proviso that it is an artificial grouping – in my opinion<

That was the point of tagging, yet you have some sort of objection to tagging!

Stephen

--------------------------------------------
On Fri, 3/10/14, John Grehan <calabar.john at gmail.com> wrote:

 Subject: Re: [Taxacom] Paraphyletic groups as natural units of biological classification
 To: "Stephen Thorpe" <stephen_thorpe at yahoo.co.nz>
 Cc: "Curtis Clark" <lists at curtisclark.org>, "taxacom at mailman.nhm.ku.edu" <taxacom at mailman.nhm.ku.edu>, "AlanWeakley" <weakley at bio.unc.edu>, "Kenneth Kinman" <kinman at hotmail.com>
 Received: Friday, 3 October, 2014, 10:18 AM
 
 
 
 Hi Stephen,
 
 With respect to your
 comment “I think what you are saying is
 that a paraphyletic group is one which has no known
 synapomorphies (e.g. MM
 minus M), even though it could later be shown to be
 monophyletic (i.e. sister
 taxon to M) if synapomorphies were discovered. My point,
 however, is such paraphyletic
 groups may be commonplace, and it may never be possible to
 discover
 synapomorphies. “
 
 
 
 My counter point is that a
 paraphyletic group is not a group
 at all in the natural sense of monophyly. 
 
 
 
 “Therefore, if we were
 to try to force a Linnean
 classification to be strictly monophyletic, we would have a
 problem. One
 possible solution is to reject Linnean classification in
 favour of a rankless
 phylogenetic classification, but this has the major
 disadvantage of rendering a
 vast amount of published information obsolete. I think it is
 far more sensible
 to retain Linnean classification, with formally names and
 ranks for
 paraphyletic groups.”
 
 
 
 My view is that there is
 no problem of Linnean classification
 if it is limited to being applied to monophyletic groups. If
 one wants to apply
 a name or label to a paraphyletic assemblage then there is
 nothing to prevent
 that usage, only with the proviso that it is an artificial
 grouping – in my
 opinion.
 
 
 
 “All we need to do is tag these names somehow as being
 paraphyletic, such as by
 putting the name in double quotes (e.g.
 "Reptilia"), but they are
 still formal names, governed by the appropriate code of
 nomenclature (actually
 not in the case of Reptilia, which is unregulated by the
 ICZN). This way, the
 results of phylogenetic studies is not necessarily to change
 the
 classification, but just to tag names for paraphyletic
 taxa.”
 
 
 
 Personally I would not add
 paraphyletic labels to a
 phylogenetic assemblage in any formal way. Informal I would
 have no problem with.
 
 
 
 “A reclassification may
 still be appropriate in cases with
 very high phylogenetic support. The problems arise when
 people start rejecting
 formally named taxa just because they are paraphyletic
 according to your
 definition (i.e. based on no known synapomorphies).”
 
 One either rejects the
 formal name, or extends it to include
 all members encompassed by the defining synapomorphy or
 synapomorphies.
 
  
 
 “Not sure how much sense
 this makes, and apologies for any
 "using words any old way I like" .
 
 Stephen”
 
 
 
 I’m never sure how much
 sense I make and periodically some people say as much - ha
 ha. So no worries.
 
 
 
 John Grehan
 
 
 On Thu, Oct 2, 2014 at 4:33
 PM, Stephen Thorpe <stephen_thorpe at yahoo.co.nz>
 wrote:
 John,
 
 I think what you are saying is that a paraphyletic group is
 one which has no known synapomorphies (e.g. MM minus M),
 even though it could later be shown to be monophyletic (i.e.
 sister taxon to M) if synapomorphies were discovered. My
 point, however, is such paraphyletic groups may be
 commonplace, and it may never be possible to discover
 synapomorphies. Therefore, if we were to try to force a
 Linnean classification to be strictly monophyletic, we would
 have a problem. One possible solution is to reject Linnean
 classification in favour of a rankless phylogenetic
 classification, but this has the major disadvantage of
 rendering a vast amount of published information obsolete. I
 think it is far more sensible to retain Linnean
 classification, with formally names and ranks for
 paraphyletic groups. All we need to do is tag these names
 somehow as being paraphyletic, such as by putting the name
 in double quotes (e.g. "Reptilia"), but they are
 still formal names,
 
  governed by the appropriate code of nomenclature (actually
 not in the case of Reptilia, which is unregulated by the
 ICZN). This way, the results of phylogenetic studies is not
 necessarily to change the classification, but just to tag
 names for paraphyletic taxa. A reclassification may still be
 appropriate in cases with very high phylogenetic support.
 The problems arise when people start rejecting formally
 named taxa just because they are paraphyletic according to
 your definition (i.e. based on no known synapomorphies). Not
 sure how much sense this makes, and apologies for any
 "using words any old way I like" ...
 
 Stephen
 
 --------------------------------------------
 
 On Thu, 2/10/14, John Grehan
 <calabar.john at gmail.com>
 wrote:
 
 
 
  Subject: Re: [Taxacom] Paraphyletic groups as natural
 units of biological classification
 
  To: "Stephen Thorpe" <stephen_thorpe at yahoo.co.nz>
 
  Cc: "Curtis Clark" <lists at curtisclark.org>,
 "taxacom at mailman.nhm.ku.edu"
 <taxacom at mailman.nhm.ku.edu>,
 "AlanWeakley" <weakley at bio.unc.edu>,
 "Kenneth Kinman" <kinman at hotmail.com>
 
  Received: Thursday, 2 October, 2014, 10:52 PM
 
 
 
  My
 
  question was aimed at the issue of whether or not
 
  paraphyletic groups can be identified in the absence of
 
  evidence that shows that they are artificial divisions
 
  within a monophyletic group (i.e. that artificially
 exclude
 
  some members, usually because the subdivision is based on
 a
 
  preference for plesiomorphies). If there is no direct
 
  evidence for sustaining a paraphyletic grouping that
 
  represents the actual sequence of phylogenetic
 relationship
 
  (as then known according to the systematics evidence),
 then
 
  paraphyletic groups have no real existence in terms of
 
  phylogenetic sequence. I would say that we would know
 that
 
  MM minus M (and I had no problem with the language here)
 is
 
  paraphyletic if the group MM plus M is already shown to
 be
 
  monophyletic. Of course, it is always possible that
 
  subsequent research may reveal sufficient character
 evidence
 
  (molecular or morphological) to change the phylogeny
 where
 
  MM becomes a monophyletic group and M is its sister
 taxon.
 
  Admittedly my knowledge of systematics theory is pretty
 
  limited so I will not be surprised if the above is found
 to
 
  be nonsense, but I would then be interested to
 understand
 
  why.
 
 
 
  John Grehan
 
 
 
  On Wed, Oct 1, 2014 at 3:28
 
  PM, Stephen Thorpe <stephen_thorpe at yahoo.co.nz>
 
  wrote:
 
  Explain
 
  the question a bit more, please! I was trying to say
 that
 
  the remainder (MM minus M) may or may not be
 paraphyletic,
 
  and we could never know. There would not however be any
 
  evidence for monophyly, either
 
 
 
 
 
 
 
  Stephen
 
 
 
 
 
 
 
  --------------------------------------------
 
 
 
  On Wed, 1/10/14, John Grehan
 
  <calabar.john at gmail.com>
 
  wrote:
 
 
 
 
 
 
 
   Subject: Re: [Taxacom] Paraphyletic groups as natural
 
  units of biological classification
 
 
 
   To: "Stephen Thorpe" <stephen_thorpe at yahoo.co.nz>
 
 
 
   Cc: "Curtis Clark" <lists at curtisclark.org>,
 
  "taxacom at mailman.nhm.ku.edu"
 
  <taxacom at mailman.nhm.ku.edu>,
 
  "AlanWeakley" <weakley at bio.unc.edu>,
 
  "Kenneth Kinman" <kinman at hotmail.com>
 
 
 
   Received: Wednesday, 1 October, 2014, 11:01 PM
 
 
 
 
 
 
 
   Where, then, is the evidence for
 
 
 
   paraphyly?
 
 
 
 
 
 
 
   John
 
 
 
   Grehan
 
 
 
 
 
 
 
   On Tue, Sep 30, 2014 at
 
 
 
   8:14 PM, Stephen Thorpe <stephen_thorpe at yahoo.co.nz>
 
 
 
   wrote:
 
 
 
   I suspect
 
 
 
   that evolution is intrinsically paraphyletic, and
 that
 
  such
 
 
 
   widespread paraphyly can never be cracked, simply
 
  because
 
 
 
   there is no extant evidence to identify sister taxa
 in
 
  many
 
 
 
   cases. I'm thinking of a scenario along these
 lines:
 
  We
 
 
 
   have an obviously monophyletic group M, belonging to
 
  another
 
 
 
   obviously monophyletic group MM. But MM minus M is
 just
 
  a
 
 
 
   bunch of plesiomorphic species, with no one (or more)
 
  of
 
 
 
   them having a synapomorphy with M. There could be just
 a
 
  few
 
 
 
   of these species, or there could be a great many.
 
  Together
 
 
 
   they could be a monophyletic group (without any
 
 
 
   synapomorphies!), or one (or more) of them could be
 
  more
 
 
 
   closely related to M (but again with no
 synapomorphies!)
 
  We
 
 
 
   can never know. All it would take is for M to evolve
 
  rapidly
 
 
 
   along its own evolutionary trajectory (perhaps a
 small
 
 
 
   isolated population), and "leaving no
 history",
 
  so
 
 
 
   to speak!
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   Stephen
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   --------------------------------------------
 
 
 
 
 
 
 
   On Wed, 1/10/14, Kenneth Kinman <kinman at hotmail.com>
 
 
 
   wrote:
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    Subject: RE: [Taxacom] Paraphyletic groups as
 natural
 
 
 
   units of biological classification
 
 
 
 
 
 
 
    To: "Stephen Thorpe" <stephen_thorpe at yahoo.co.nz>,
 
 
 
   "Curtis Clark" <lists at curtisclark.org>,
 
 
 
   "taxacom at mailman.nhm.ku.edu"
 
 
 
   <taxacom at mailman.nhm.ku.edu>,
 
 
 
   "AlanWeakley" <weakley at bio.unc.edu>
 
 
 
 
 
 
 
    Received: Wednesday, 1 October, 2014, 11:44 AM
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    #yiv5322393153 #yiv5322393153 --
 
 
 
 
 
 
 
    .yiv5322393153hmmessage P
 
 
 
 
 
 
 
    {
 
 
 
 
 
 
 
    margin:0px;padding:0px;}
 
 
 
 
 
 
 
    #yiv5322393153 body.yiv5322393153hmmessage
 
 
 
 
 
 
 
    {
 
 
 
 
 
 
 
    font-size:12pt;font-family:Calibri;}
 
 
 
 
 
 
 
    #yiv5322393153
 
 
 
 
 
 
 
    Hi Stephen,
 
 
 
 
 
 
 
            I agree with you that
 
 
 
 
 
 
 
    angiosperm classification is not a typical case
 
  (having
 
 
 
   been
 
 
 
 
 
 
 
    so intensely studied and most of the higher taxa
 
  being
 
 
 
 
 
 
 
    extant).  Most cases involve a basal paraphyletic
 
 
 
   remainder
 
 
 
 
 
 
 
    (I don't like calling them a residue) that is
 
  either
 
 
 
   too
 
 
 
 
 
 
 
    hard to crack or won't be cracked for a long
 
  time. 
 
 
 
   But
 
 
 
 
 
 
 
    even in the case of angiosperms, I believe it is
 more
 
 
 
 
 
 
 
    memorable (and intuitive) and extremely useful to
 
 
 
   divide
 
 
 
 
 
 
 
    angiosperms into just three formal classes
 
  (Liliopsida,
 
 
 
 
 
 
 
    Rosopsida, and Magnolipsida%) for monocots,
 eudicots,
 
 
 
   and
 
 
 
 
 
 
 
    the paraphyletic basal remainder.  As I recall,
 
 
 
   Stuessy
 
 
 
 
 
 
 
    (2010) recognized the same three classes, but with
 
 
 
 
 
 
 
    non-typified names (calling the basal remainder
 
 
 
 
 
 
 
    Archaeangiospermae).  I suppose one could put the
 
 
 
 
 
 
 
    paraphyletic group in quotes, but I still prefer to
 
  mark
 
 
 
   it
 
 
 
 
 
 
 
    with the % symbol (and Cavalier-Smith just uses an
 
 
 
 
 
 
 
    asterisk).              
 
 
 
 
 
 
 
      
 
 
 
 
 
 
 
             I've long thought that it would
 
 
 
   become
 
 
 
 
 
 
 
    obvious that the pendulum swing to purely
 
  holophyletic
 
 
 
 
 
 
 
    classifications ("cladifications", as
 Mayr
 
 
 
   called
 
 
 
 
 
 
 
    them) had too many drawbacks that it would become
 
 
 
   glaringly
 
 
 
 
 
 
 
    apparent that it was causing as much harm as good.
 
 
 
 
 
 
 
     Unfortumately the followers of Hennig have been
 
  swayed
 
 
 
   by
 
 
 
 
 
 
 
    the successes and blissfully ignore the failures.
  
 
   
 
 
 
    
 
 
 
 
 
 
 
                                    
 
 
 
 
 
 
 
        The biggest failure is the supposed holophyly
 
  of
 
 
 
   three
 
 
 
 
 
 
 
    Domains of life, which still has widespread support
 
 
 
   even
 
 
 
 
 
 
 
    though it has been thoroughly discredited by some
 of
 
 
 
   the
 
 
 
 
 
 
 
    greatest minds in biology.  Such a simple
 
  explanation
 
 
 
   of
 
 
 
 
 
 
 
    the tree of life is just... simplistic (and the
 
  result
 
 
 
   of
 
 
 
 
 
 
 
    using Archaebacteria to root the Eubacteria), but
 the
 
 
 
   more
 
 
 
 
 
 
 
    likely alternative trees are unfortunately more
 
  complex
 
 
 
   and
 
 
 
 
 
 
 
    will take much more data and time to sway the
 
  majority.
 
 
 
 
 
 
 
     Only then will that majority finally return to
 
 
 
   dividing
 
 
 
 
 
 
 
    cellular life into its two fundamental
 organizational
 
 
 
   types
 
 
 
 
 
 
 
    (Prokaryota and Eukaryota), and finally declare
 that
 
  a
 
 
 
   Three
 
 
 
 
 
 
 
    Domain Tree based mainly on too few molecular
 
  sequences
 
 
 
   is
 
 
 
 
 
 
 
    (and always has been) a horrible mistake.      
  
 
   
 
 
 
    
 
 
 
 
 
 
 
                  
 
 
 
 
 
 
 
     
 
 
 
 
 
 
 
         Another failure is the much older debate
 over
 
 
 
   the
 
 
 
 
 
 
 
    classification and phylogeny of Metazoan phyla. 
 The
 
 
 
   clade
 
 
 
 
 
 
 
    Ecdysozoa could well be truly holophyletic, but
 
  Platyzoa
 
 
 
   was
 
 
 
 
 
 
 
    recently shown to be paraphyletic, and I have been
 
 
 
   harping
 
 
 
 
 
 
 
    on the paraphyly of the supposed "clade"
 
 
 
 
 
 
 
    Lophotrochosa even since it was proposed almost 20
 
 
 
   years
 
 
 
 
 
 
 
    ago.    Of
 
 
 
 
 
 
 
    course, the damage has been even greater at lower
 
 
 
   taxonomic
 
 
 
 
 
 
 
    ranks, since there are a lot more taxa at such
 ranks.
 
 
 
 
 
 
 
     Vertebrates classes are now a taxonomic mess
 (even
 
 
 
   though
 
 
 
 
 
 
 
    heavily studied).   
 
 
 
 
 
 
 
       
 
 
 
 
 
 
 
        ------------------------Ken     
 
 
 
 
 
 
 
      
 
 
 
 
 
 
 
    ----------------------------------------------------------------------------------------------------------------
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    > Date: Sat, 27 Sep
 
 
 
 
 
 
 
    2014 20:29:39 -0700
 
 
 
 
 
 
 
    > From:
 
 
 
 
 
 
 
    stephen_thorpe at yahoo.co.nz
 
 
 
 
 
 
 
    > To:
 
 
 
 
 
 
 
    lists at curtisclark.org;
 
 
 
   taxacom at mailman.nhm.ku.edu;
 
 
 
 
 
 
 
    weakley at bio.unc.edu
 
 
 
 
 
 
 
    > Subject: Re:
 
 
 
 
 
 
 
    [Taxacom] Paraphyletic groups as natural units of
 
 
 
 
 
 
 
    biological     classification
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    > But this example doesn't illustrate
 
 
 
 
 
 
 
    the terms of the debate, as I see it. As you
 describe
 
 
 
   the
 
 
 
 
 
 
 
    example, we have a rare case of an uncontroversial
 
  and
 
 
 
   fully
 
 
 
 
 
 
 
    determined monophyletic classification of flowering
 
 
 
   plants
 
 
 
 
 
 
 
    which leaves (no pun intended!) no paraphyletic
 
 
 
   residue.
 
 
 
 
 
 
 
    Examples of this kind are rare, I suggest, and the
 
 
 
   typical
 
 
 
 
 
 
 
    case involved only moderately supported phylogenies
 
  and
 
 
 
   a
 
 
 
 
 
 
 
    basal paraphyletic residue that is too hard to
 crack.
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    > Stephen
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    --------------------------------------------
 
 
 
 
 
 
 
    > On Sun, 28/9/14, Weakley, Alan
 
 
 
 
 
 
 
    <weakley at bio.unc.edu>
 
 
 
   wrote:
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  Subject: Re: [Taxacom] Paraphyletic
 
 
 
 
 
 
 
    groups as natural units of biological
 classification
 
 
 
 
 
 
 
    >  To: "Curtis Clark"
 
 
 
 
 
 
 
    <lists at curtisclark.org>,
 
 
 
 
 
 
 
    "taxacom at mailman.nhm.ku.edu"
 
 
 
 
 
 
 
    <taxacom at mailman.nhm.ku.edu>
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    Received: Sunday, 28 September, 2014, 3:09 PM
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  Here seems to
 
 
 
 
 
 
 
    be
 
 
 
 
 
 
 
    >  "the thing". 
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  The "basal
 
 
 
 
 
 
 
    angiosperms" or
 
 
 
 
 
 
 
    >  "primitive
 
 
 
 
 
 
 
    dicots" or "ANITA and the
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    Magnoliids" or...  are clearly a basal grade
 to
 
 
 
 
 
 
 
    other
 
 
 
 
 
 
 
    >  angiosperms, based on all recent
 
 
 
 
 
 
 
    analyses.  Amborellales
 
 
 
 
 
 
 
    >  sister to all
 
 
 
 
 
 
 
    other angiosperms.  Then Nymphaeales sister
 
 
 
 
 
 
 
    >  to all the rest, then...  ETC.  Whether
 
 
 
 
 
 
 
    you have access to
 
 
 
 
 
 
 
    >  all the papers, a
 
 
 
 
 
 
 
    good summary of the current consensus can
 
 
 
 
 
 
 
    >  be had online at the Angiosperm Phylogeny
 
 
 
 
 
 
 
    Website, at MoBot,
 
 
 
 
 
 
 
    >  compiled by Peter
 
 
 
 
 
 
 
    Stevens.  This clearly shows a grade of
 
 
 
 
 
 
 
    >  various orders (all small, currently) and
 
 
 
 
 
 
 
    then also the
 
 
 
 
 
 
 
    >  magnoliids (mostly
 
 
 
 
 
 
 
    small, currently, except especially, the
 
 
 
 
 
 
 
    >  Lauraceae and somewhat less so the
 
 
 
 
 
 
 
    Piperaceae).
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    So, the "basal
 
 
 
 
 
 
 
    >  angiosperms"
 
 
 
 
 
 
 
    are not monophyletic.  And yet, it is
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    "useful" and "convenient" to
 
  refer
 
 
 
   to
 
 
 
 
 
 
 
    >  them as a group -- to classify them as a
 
 
 
 
 
 
 
    unit.  In
 
 
 
 
 
 
 
    >  teaching, and in floras
 
 
 
 
 
 
 
    (Flora of Virginia 2012, Flora of
 
 
 
 
 
 
 
    >  the
 
 
 
 
 
 
 
    Southern and Mid-Atlantic States 2014)), it is
 
 
 
 
 
 
 
    >  "handy" ("useful") to
 
 
 
 
 
 
 
    divide the
 
 
 
 
 
 
 
    >  vascular flora into: 
 
 
 
 
 
 
 
    Lycophytes, Ferns, Basal Angiosperms,
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    Monocots, and Eudicots.  It seems
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    "disproportionate" to treat 4 or more
 units
 
 
 
 
 
 
 
    >  (small, currently, a genus or two, a
 
 
 
 
 
 
 
    hundred species or
 
 
 
 
 
 
 
    >  less, each) at
 
 
 
 
 
 
 
    equivalent rank to Monocots or Eudicots,
 
 
 
 
 
 
 
    >  which have many more orders, families,
 
 
 
 
 
 
 
    genera, and
 
 
 
 
 
 
 
    >  species.  Especially, as
 
 
 
 
 
 
 
    their morphological  differences
 
 
 
 
 
 
 
    >  seem
 
 
 
 
 
 
 
    relatively obscure, abstruse, and non-obvious.  If
 
  the
 
 
 
 
 
 
 
    >  morphological distinctions were
 
 
 
 
 
 
 
    completely obvious, maybe we
 
 
 
 
 
 
 
    >  would be
 
 
 
 
 
 
 
    more accepting -- no-one seems to have a hard time
 
 
 
 
 
 
 
    >  with Ginkgo or Welwitschia as (modern)
 
 
 
 
 
 
 
    monotypes: 
 
 
 
 
 
 
 
    >  uncontroversial monotypic
 
 
 
 
 
 
 
    orders. 
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  So,
 
 
 
 
 
 
 
    Judd et al., for instance, in their
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    textbook, Plant Taxonomy: a Phylogenetic Approach,
 
  use
 
 
 
 
 
 
 
    >  quotes to indicate units that are not
 
 
 
 
 
 
 
    monophyletic but yet
 
 
 
 
 
 
 
    >  are
 
 
 
 
 
 
 
    "useful".  There is an interesting
 tension
 
 
 
 
 
 
 
    >  here between "strict monophyly"
 
 
 
 
 
 
 
    and
 
 
 
 
 
 
 
    >  "intuitive (useful)
 
 
 
 
 
 
 
    classification
 
 
 
 
 
 
 
    >  units".   Units
 
 
 
 
 
 
 
    with quotes seem to flag
 
 
 
 
 
 
 
    >  something
 
 
 
 
 
 
 
    like "this is not monophyletic but sure is
 
 
 
 
 
 
 
    >  handy so we will keep using it
 
 
 
 
 
 
 
    informally".
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  I'm not taking sides here
 
 
 
 
 
 
 
    >  (I am conflicted).  But...  it may be
 
 
 
 
 
 
 
    instructive to
 
 
 
 
 
 
 
    >  contemplate that other
 
 
 
 
 
 
 
    "intuitive (useful)
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    classification units" ("plants",
 
 
 
 
 
 
 
    >  "animals", "algae",
 
 
 
 
 
 
 
    "fungi",
 
 
 
 
 
 
 
    >  "birds",
 
 
 
 
 
 
 
    "bacteria",
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    "slime-molds", ) have fared increasingly
 
 
 
   poorly
 
 
 
 
 
 
 
    >  over time as real classification units. 
 
 
 
 
 
 
 
    I was taught as a
 
 
 
 
 
 
 
    >  college botany
 
 
 
 
 
 
 
    student in the 1970s that there were 2 main
 
 
 
 
 
 
 
    >  types of algae (a kind of plant): 
 
 
 
 
 
 
 
    prokaryotic
 
 
 
 
 
 
 
    >  ("blue-green
 
 
 
 
 
 
 
    algae") and eukaryotic (green, red,
 
 
 
 
 
 
 
    >  brown, etc., algae) --  several decades
 
 
 
 
 
 
 
    on, this looks
 
 
 
 
 
 
 
    >  laughable (and in no
 
 
 
 
 
 
 
    way "useful" or
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    "convenient" in any respect).  On the
 
  other
 
 
 
 
 
 
 
    hand,
 
 
 
 
 
 
 
    >  the "Basal
 
 
 
 
 
 
 
    Angiosperms" seem a "useful"
 
 
 
 
 
 
 
    >  unit for teaching and organization and
 
 
 
 
 
 
 
    classification, even
 
 
 
 
 
 
 
    >  if monophyly is
 
 
 
 
 
 
 
    uncertain or even disproved... 
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  -----Original Message-----
 
 
 
 
 
 
 
    >  From: Taxacom
 
 
 
 
 
 
 
    [mailto:taxacom-bounces at mailman.nhm.ku.edu]
 
 
 
 
 
 
 
    >  On Behalf Of Curtis Clark
 
 
 
 
 
 
 
    >  Sent: Saturday,
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    September 27, 2014 9:29 PM
 
 
 
 
 
 
 
    >  To:
 
 
 
 
 
 
 
    taxacom at mailman.nhm.ku.edu
 
 
 
 
 
 
 
    >  Subject:
 
 
 
 
 
 
 
    Re: [Taxacom] Paraphyletic groups as
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    natural units of biological classification
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  On 2014-09-27 6:59
 
 
 
 
 
 
 
    AM, John
 
 
 
 
 
 
 
    >  Grehan wrote:
 
 
 
 
 
 
 
    >  > Since you have some
 
 
 
 
 
 
 
    >  expertise and strong opinions on
 
 
 
 
 
 
 
    paraphyly I
 
 
 
 
 
 
 
    >  > presume you have
 
 
 
 
 
 
 
    read the citation of
 
 
 
 
 
 
 
    >  Stuessy (2010) on
 
 
 
 
 
 
 
    basal
 
 
 
 
 
 
 
    >  > angiosperms
 
 
 
 
 
 
 
    >  being a paraphyletic group. As I do not
 
 
 
 
 
 
 
    have immediate
 
 
 
 
 
 
 
    >  > access to that
 
 
 
 
 
 
 
    paper perhaps you could
 
 
 
 
 
 
 
    >  describe in
 
 
 
 
 
 
 
    what way that group was paraphyletic.
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    >  Some of its members
 
 
 
 
 
 
 
    >  (Austrobaileyaceae?) are more closely
 
 
 
 
 
 
 
    related to the rest of
 
 
 
 
 
 
 
    >  the angiosperms
 
 
 
 
 
 
 
    than others are. (Same definition as
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    usual.)
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  --
 
 
 
 
 
 
 
    >  Curtis Clark       
 
 
 
 
 
 
 
    http://www.csupomona.edu/~jcclark
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    Biological Sciences               
 
 
 
 
 
 
 
    >     +1 909 869
 
 
 
   4140
 
 
 
 
 
 
 
    >  Cal Poly
 
 
 
 
 
 
 
    >  Pomona,
 
 
 
 
 
 
 
    Pomona CA 91768
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    _______________________________________________
 
 
 
 
 
 
 
    >  Taxacom Mailing List
 
 
 
 
 
 
 
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     Taxacom at mailman.nhm.ku.edu
 
 
 
 
 
 
 
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    >  The Taxacom Archive back to 1992 may
 
 
 
 
 
 
 
    be
 
 
 
 
 
 
 
    >  searched at:
 
 
 
 
 
 
 
    http://taxacom.markmail.org
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  Celebrating 27 years of
 
 
 
 
 
 
 
    >  Taxacom in 2014.
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    _______________________________________________
 
 
 
 
 
 
 
    >  Taxacom Mailing List
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
     Taxacom at mailman.nhm.ku.edu
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
 
 
 
 
 
 
 
    >  The Taxacom Archive back to 1992 may
 
 
 
 
 
 
 
    be
 
 
 
 
 
 
 
    >  searched at:
 
 
 
 
 
 
 
    http://taxacom.markmail.org
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    >  Celebrating 27 years of
 
 
 
 
 
 
 
    >  Taxacom in 2014.
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    _______________________________________________
 
 
 
 
 
 
 
    > Taxacom Mailing List
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    Taxacom at mailman.nhm.ku.edu
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
 
 
 
 
 
 
 
    > The Taxacom Archive back to 1992 may be
 
 
 
 
 
 
 
    searched at: http://taxacom.markmail.org
 
 
 
 
 
 
 
    >
 
 
 
 
 
 
 
    > Celebrating 27 years
 
 
 
 
 
 
 
    of Taxacom in 2014.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   _______________________________________________
 
 
 
 
 
 
 
   Taxacom Mailing List
 
 
 
 
 
 
 
   Taxacom at mailman.nhm.ku.edu
 
 
 
 
 
 
 
   http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
 
 
 
 
 
 
 
   The Taxacom Archive back to 1992 may be searched at: http://taxacom.markmail.org
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
   Celebrating 27 years of Taxacom in 2014.
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 
 



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