peter.stevens at MOBOT.ORG
Mon Mar 27 12:44:05 CST 2006
When APG started, lumps roughly equivalent to contemporary orders
seemed stable (also families, of course), hence the emphasis on those
two groupings. There is still considerable uncertainty about many of
the relationships between orders (inc. where Chloranthaceae go) -
indeed, quite a number of the deeper barnches are uncertain. Perhaps
a more detailed classification will be developed (although some find
them very cumbersome), perhaps informal names like asterids will be
kept. Of course, some like a resolved classification, but I do not
think Thorne holds to the principle of monophyly.
Note also that all taxa do not have to be placed in e.g. subclasses.
This is the so-called "Principle of Exhaustive Subdivision", and is
not mandated by the ICBN (but its application, as here, leads to the
production of empty ranks, and it is one of the reasonable criticisms
of proponents of the PhyloCode.
>It is heartening to know that Agiosperm Phylogeny Group is attempting at a
>phylogenetic classification recognising monophyletic groups, but in the
>process abandoning supraordinal ranks. In an effort to arrive at a consenses
>classification, why not think of taxonomic groups which are monophyletic but
>also preserve the Linnaean hierarchy. Thorne to me is one author who is
>keeping track of recent phylogenetic developments and balancing it with
>hierarchical grouping. He did this in 2003 when APG II was published and I
>find many parallels between two diverse approaches. He has since improved
>his classification by establishing Chloranthidae as eleventh (first infact
>of eleven subclasses), whereas APG II has made no substantial revision. Is
>we can recognise Commelinids as monophyletic informal group, what is wrong
>with subclass Commelinidae, and so on.
> Let consenses be to find a compromise between Linnaean and Phylogenetic
>taxonomy. Thorne has shown us the way.
>Dr. Gurcharan Singh
>Department of Botany
>Sri Guru Tegh Bahadur Khalsa College
>University of Delhi, Delhi-110007, INDIA
>Res: 25518297, 9810359089
>e-mail: singhg at satyam.net.in
>ak_932 at sify.com
>----- Original Message -----
>From: "Peter Stevens" <peter.stevens at MOBOT.ORG>
>To: <TAXACOM at LISTSERV.NHM.KU.EDU>
>Sent: Friday, March 24, 2006 8:16 PM
>Subject: Re: Consensus
> >I wanted to send these a couple of days ago, but pressed the wrong
>> button - they still seem to be relevant. And I have added a
>> paragraph from a Yanega/Delaporte excahnge which is relevant.
>>> Perhaps an independent effort by Google would actually be
>>>helpful, not only in speeding up the process, but perhaps provide a
>>>superior product that might force other projects to improve their
>> I would only hope they would take a top-down approach to
>> classification, something for which many other projects (including
>> Species 2000) have done a pretty sloppy job. (from Ken)
>> I don't pretend to know much about things other then seed plants, and
>> not too much even there, but I would remind you that there are a
>> number of us in the botanical community who are trying to develop a
>> consensus classification - phylogeny based, in this case (the
>> Angiosperm Phylogeny Group classification - e.g. see
>>, etc. Textbooks, and now
>> botanic gardens and herbaria, are adopting it - and if we have a
>> consensus classification, it will allow us to spend time on things
>> that really matter, like understanding evolution, producing
>> phylogenies in areas where we have none, working on species limits,
>> There are are almost imnnumerable possible classifications whether
>> phylogeny based or not, and so to spend time arguing which is "best"
>> is simply a waste of time, so long as you agree about the underlying
>> principles (Ken, could you please pass on this opportunity to tell us
> > for the umpteenth time why the Kinman system is best?). Any
>> classification/naming system that is in general use will have to be
>> some sort of consensus system.
>> At 12:05 PM -0600 3/22/06, pierre deleporte wrote:
>>> 11:45 21/03/2006 -0800, Doug Yanega wrote :
>>>>taxonomists themselves will never express a UNANIMOUS agreement on any
>>>>classification. Our job, however, is to either supply the remainder
>>>>of the scientific and civilian communities with a single
>>>>classification or LOSE our jobs. The inability to give a clear
>>>>answer to any classificatory question we are asked is the major
>>>>reason for (1) sociopolitical pressure to relegate taxonomists to
>>>>obsolescence, and (2) splinter groups like the PhyloCode crowd.
>>>Maybe there is a deeper, philosophical reason: no unique, universal
>>>classification fitting all possible purposes is conceivable.
>>>Any classification is a convenient human construct, hopefully of
>>>some use, and of optimal use in the best of cases. The myth of a
>>>unique-optimal (or worse: self-evident) classification (be it called
>>>"natural" by any imaginable criterion) is obsolete .
>> Pierre is of course dead right. But is consensus impossible?
>> On another matter, I was corresponding with a colleague in Holland
>> who takes students on field trips, and he noted that students no
>> longer wanted to learn common names - they got more info about the
>> plant in web searches by using the latin name. Think what you would
>> uncover if you searched for "Ladies tresses" (Spiranthes), etc., etc.
>> Of course, there are still interesting possibilities when using the
>> latin name, as Rod Page mentioned when he introduced his
>> ispecies.org, and I have indeed found some of these...
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