[Taxacom] Elimination of paraphyly: sensible or not?

[John Grehan]

It's hard to judge all the efficacy of classification approaches for all
the different groups out there unless one is well versed in them all, which
I am not. So I will limit comment to a case for which I have direct
experience. This concerns the group known as 'great apes' which was once a
formal taxonomic group (separate from humans). These were once considered
to comprise a natural group. With recognition that either chimps or orangs
are more closely related to humans than to other great apes, the group
'great apes' was discontinued as a unit of classification by, as far as I
am aware, everybody active in the systematics game. Seems to me that this
is one clear case of paraphyly being rejected by cladists and non cladists.
Of course the label 'great apes' is still used and is useful in the way it
is used, but it is not used as a formal systematic or taxonomic entity.

John Grehan


On Thu, Feb 8, 2018 at 9:59 PM, Kenneth Kinman <kinman at hotmail.com> wrote:

> Hi all,
>         One example I gave of the unfortunate attempt to eliminate
> paraphyly is Class Sarcopterygii (with respect to the clade containing the
> four Classes of Tetrapoda).   The Wikipedia article (
> https://en.wikipedia.org/wiki/Sarcopterygii ) has a beautiful tree in the
> Phylogeny section, but then in the Classification section comes up with
> this attempt to avoid paraphyly:
>
>
> Subclass Sarcopterygii
>
>   *   †Order Onychodontida<https://en.wikipedia.org/wiki/Onychodontida>
>   *   Order Actinistia<https://en.wikipedia.org/wiki/Actinistia>
>   *   Infraclass Dipnomorpha<https://en.wikipedia.org/wiki/Dipnomorpha>
>      *   †Order Porolepiformes<https://en.wikipedia.org/wiki/
> Porolepiformes>
>      *   Subclass Dipnoi<https://en.wikipedia.org/wiki/Dipnoi>
>         *   Order Ceratodontiformes<https://en.wikipedia.org/wiki/
> Ceratodontiformes>
>         *   Order Lepidosireniformes<https://en.wikipedia.org/wiki/
> Lepidosireniformes>
>   *   Infraclass Tetrapodomorpha<https://en.wikipedia.org/wiki/
> Tetrapodomorpha>
>      *   †Order Rhizodontida<https://en.wikipedia.org/wiki/Rhizodontida>
>      *   Superorder Osteolepidida<https://en.wikipedia.org/wiki/
> Osteolepidida>
>         *   †Order Osteolepiformes<https://en.
> wikipedia.org/wiki/Osteolepis>
>            *   †Family Tristichopteridae<https://en.wikipedia.org/wiki/
> Tristichopteridae>
>         *   †Order Panderichthyida<https://en.wikipedia.org/wiki/
> Panderichthys>
>         *   Superclass Tetrapoda<https://en.wikipedia.org/wiki/Tetrapoda>
>
>      And then there is the even more unfortunate Wikipedia article
> "Cladistic Classification of Class Sarcopterygii" (
> https://en.wikipedia.org/wiki/Cladistic_Classification_of_
> Class_Sarcopterygii ) which is even worse because it doesn't include
> fossil taxa.  Aves is a "Subcohort", and Mammalia is a Parvclass.
>
>       As Ernst Mayr would say, these are cladifications, not
> classifications.  And all it takes is one new fossil discovery to cause
> these cladifications to drastically change, while a classification with a
> paraphyletic Class Sarcopterygii would remain relatively stable.
>
>                    -----------------------Ken
>
>
>
> _______________________________________________
> 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
>
> Send Taxacom mailing list submissions to taxacom at mailman.nhm.ku.edu
> To subscribe or unsubscribe via the Web, visit:
> http://mailman.nhm.ku.edu/cgi-bin/mailman/listinfo/taxacom
> You can reach the person managing the list at:
> taxacom-owner at mailman.nhm.ku.edu
>
> Nurturing Nuance while Assaulting Ambiguity for 31 Some Years, 1987-2018.
>