Message 2002-02-0004: Re: interesting style of definition

Thu, 14 Feb 2002 14:47:55 -0500 (EST)

[Previous by date - Re: interesting style of definition]
[Next by date - Crown clade definitions (was: Re: interesting style of definition)]
[Previous by subject - Re: interesting style of definition]
[Next by subject - Re: interesting style of definition]

Date: Thu, 14 Feb 2002 14:47:55 -0500 (EST)
From: "T. Mike Keesey" <>
To: -PhyloCode Mailing List- <>
Subject: Re: interesting style of definition

On Thu, 14 Feb 2002, Mieczyslaw Wolsan wrote:

> There are at least three problems with this definition. First, the clade
> referred to by the definition changes with the extinction of taxa; and this
> is the most serious problem.

Perhaps if "extant" were emended to "extant at this time". We'd still have
a problem, though, if a previously unknown extant outgroup were found.
"Currently known to be extant"? "Currently published and extant species"?

> Second, it is not clear whether "the last common ancestor" is contained
> in the clade or not (as a non-native English speaker I cannot evaluate
> this properly, but I do not think that the word "stemming" specifies
> this unambiguously).

I think it does. PhyloCode uses that word, doesn't it?

> Third, "the last common ancestor"  may refer to either a species or a
> population, or a breeding pair, individual organism, etc.; in each
> instance, we have to do with a different clade. This might seem like
> extreme pedantry, but if explicitness in phylogenetic nomenclature is
> important, this should be reflected in the wording of phylogenetic
> definitions.

Well, PhyloCode says it's a species, right? (The article does say it's
adhering to PhyloCode rules ... although, as I pointed out, this style of
definitions doesn't seem to....)

 The Dinosauricon        <>
  BloodySteak             <>
   personal                <> --> <>
    Dinosauricon-related    <>
     AOL Instant Messenger   <Ric Blayze>
      ICQ                     <77314901>
       Yahoo! Messenger        <Mighty Odinn>


Feedback to <> is welcome!