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Re: Hanson 2006, Mortimer, Baeker response

Tim Williams writes:
>> I highly doubt it.  I don't think we're living in such a
>> monophyly-thought-police world quite yet.
> Speaking for myself, I would prefer that all named groups be
> monophyletic.  Paraphyletic groups only cause confusion (for me,
> anyway).

I'm not sure I can agree with your position.  For example, I've got
pretty bored of repeatedly writing "non-neosauropod sauropod"
recently; wouldn't it be nice just to define Eosauropoda as the
paraphyletic group (Sauropoda - Neosauropoda) and then just refer to

> For example, I don't want to back to the bad old days when Theropoda
> was paraphyletic, and birds (Aves) were excluded because they were
> considered too "different" to be put in with the theropods.

That example is misleading, because the confusion arises from two
differing candidate meanings (one monophyletic, the other not) of the
same existing name.  I agree with you that it's always bad to have
multiple meanings for a name, but that is orthogonal to whether all
names should refer to clades.

>> Ye-es.  But while we would all agree that there is an element of
>> subjectivity to beauty, I also think you'd be hard-pressed to find
>> someone who, for example, wouldn't agree that Keira Knightly and
>> Rachel Weisz are easier on the eye than Maragret Thatcher.  Now
>> think of _Tendaguria_ as Keira Knightly, _Agustinia_ as Rachel
>> Weisz and _Jobaria_ as Maragret Thatcher :-)
> This would make for an interesting character-based cladistic
> analysis.  Can you imagine examining every aspect of Ms Knightly's
> anatomy in detail?  On second thoughts, don't answer that.  ;-)

I hate to disappoint you, but you are allowed to use osteological
features and molecular sequences only :-)

>> I agree that it is polite to avoid this kind of thing where
>> possible, and foresighted to make definitions that avoid it where
>> convenient; but that's as far as I'm prepared to go.  Sometimes
>> when naming clades you just have to break whatever expectations of
>> hierarchy people may have.
> One solution is just to abandon these hierachial names altogether.
> In other words, no more names ending in -idae, -inae, -ini etc.
> Instead, we could replace them with suffixes that do not have these
> hierarchial expectations, like -aria, -odea, -ia, or -ida.

That is not bad.

Unfortunately, the world seems to be going in the precise opposite
direction, with the new version of the PhyloCode
reintroducing special suffixes!

Yes!  See Recommendation 11F on page 50:

        Recommendation 11F. Clade names created by adding
        certain prefixes or suffixes to another clade name
        (the base name) should be defined in a manner
        consistent with the hierarchical relationships implied
        by the prefix or suffix and the phylogenetic
        definition of the base name (if established), unless
        doing so would be inconsistent with the predominant
        current use of a preexisting name.
        Note 11F.1. The following prefixes and suffixes imply
        greater inclusiveness than the base name: Holo-, Pan-,
        -formes, -morpha. The following prefixes imply lesser
        inclusiveness than the base name: Eo-, Eu-, Neo-,
        Proto-. The following prefixes imply mutual
        exclusivity with the base name: Pseudo-, Para-. These
        are not intended to be exhaustive lists.


 _/|_    ___________________________________________________________________
/o ) \/  Mike Taylor  <mike@miketaylor.org.uk>  http://www.miketaylor.org.uk
)_v__/\  When a company calls its PC the `PC', and its DOS `DOS', it comes
         as little surprise when it calls its windows system `Windows'.