[Taxacom] Why stability? - Revisited

Mon May 4 20:00:35 CDT 2015

Alternatively, when taxonomists name new species, one of the following circumstances may pertain: 

(1) They base the new species on a single specimen, or several essentially identical specimens;

(2) There is a wide range of variability, in which case they need to circumscribe a concept.

Option (1) is very common.

Stephen

--------------------------------------------
On Tue, 5/5/15, Richard Pyle <deepreef at bishopmuseum.org> wrote:

 Subject: Re: [Taxacom] Why stability? - Revisited
 To: "'Jim Croft'" <jim.croft at gmail.com>, "'Weakley, Alan'" <weakley at bio.unc.edu>
 Cc: "'TAXACOM'" <taxacom at mailman.nhm.ku.edu>
 Received: Tuesday, 5 May, 2015, 9:45 AM

 The type specimens have one real
 functional role: to help decide which Linnean taxon name to
 apply to a concept.

 When taxonomists define species-level taxon concepts, one of
 three possible circumstances may exist:

 1) The concept circumscription does not include any
 individual organisms that have been designated as a
 name-bearing type for an available/validly-published Linnean
 name;

 2) The concept circumscription includes exactly one organism
 that has been designated as a name-bearing type for an
 available/validly-published Linnean name;

 3) The concept circumscription includes more than one
 organism that has been designated as a name-bearing type for
 an available/validly-published Linnean name.

 In the first circumstance, a taxonomist is prompted to
 select one individual from within the taxon concept
 circumscription to serve as the name-bearing type for a new
 Linnean name.

 In the second circumstance, the epithet associated with the
 single name-bearing type is the one that should be used to
 label the concept (which, among several possibly homotypic
 name combinations to apply is a question of classification,
 no nomenclature).

 In the third circumstance, a taxonomist must consult the
 Codes of nomenclature (and associated materials, such as
 official lists and indexes of works and names) to determine
 which, among the multiple heterotypic names has the highest
 nomenclatural priority, and this the name that should be
 applied to label the concept. These same Codes are used to
 determine which names are available/validly-published, and
 which are not.

 The principle extends to higher-rank names as well, but I
 hope that extension is reasonably evident based on a working
 knowledge of the Codes.

 Aloha,
 Rich

 Richard L. Pyle, PhD
 Database Coordinator for Natural Sciences | Associate
 Zoologist in Ichthyology | Dive Safety Officer
 Department of Natural Sciences, Bishop Museum, 1525 Bernice
 St., Honolulu, HI 96817
 Ph: (808)848-4115, Fax: (808)847-8252 email: deepreef at bishopmuseum.org
 http://hbs.bishopmuseum.org/staff/pylerichard.html

 > -----Original Message-----
 > From: Taxacom [mailto:taxacom-bounces at mailman.nhm.ku.edu]
 On Behalf Of
 > Jim Croft
 > Sent: Monday, May 04, 2015 10:36 AM
 > To: Weakley, Alan
 > Cc: TAXACOM
 > Subject: Re: [Taxacom] Why stability? - Revisited
 > 
 > This is not strictly true. The purpose of the type is
 to anchor the name, as Paul
 > describes. It is not to centre, circumscribe or in any
 way define the taxon. That
 > is a separate process that may end up including one or
 more types, and hence
 > one or more names. At least with plants. People may
 think they are defining a
 > taxon by selecting the 'best' possible type to
 represent their concept, and it is
 > probably a wise thing to do, but this is not what is
 happening according to the
 > Code. They are simply anchoring the name.
 > 
 > Jim
 >  On 05/05/2015 5:20 AM, "Weakley, Alan" <weakley at bio.unc.edu>
 wrote:
 > 
 > > The type is a flag in space around which the
 circumscription of a
 > > taxon (its concept) is defined -- usually in
 relation to other, "competing" taxa.
 > >
 > > -----Original Message-----
 > > From: Taxacom [mailto:taxacom-bounces at mailman.nhm.ku.edu]
 On Behalf
 > Of
 > > Paul van Rijckevorsel
 > > Sent: Monday, May 04, 2015 7:57 AM
 > > To: TAXACOM
 > > Subject: Re: [Taxacom] Why stability? - Revisited
 > >
 > > I was a little uneasy why Stephen Thorpe's
 attitude that taxa are
 > > defined by types is so alien to me.
 > >
 > > But it is very straightforward: from the very
 first the 'botanical'
 > > Code has laid down that nomenclatural types are
 not necessarily the
 > > most typical or representative element of a taxon
 (that is, holding
 > > only the type, it is not possible to predict with
 any degree of
 > > confidence what the taxon exactly looks
 > > like: the type is only the type) .
 > >
 > > For plants there does exist a situation where the
 whole unit is
 > > determined by a reference specimen, namely in the
 ICNCP
 > > (Cultivated-plant-Code), resulting in names of the
 type Hydrangea
 > macrophylla 'La France'.
 > >
 > > The ICNCP deals with a field of considerable
 complexity (and which
 > > does benefit from regulation), but taxonomy is not
 involved.
 > >
 > > Paul
 > > _______________________________________________
 > > Taxacom Mailing List
 > > 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 28 years of Taxacom in 2015.
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 at:
 > > http://taxacom.markmail.org
 > >
 > > Celebrating 28 years of Taxacom in 2015.
 > >
 > _______________________________________________
 > Taxacom Mailing List
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 > 
 > Celebrating 28 years of Taxacom in 2015.

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 Celebrating 28 years of Taxacom in 2015.