[Taxacom] Cyanoprokaryota help

[Dan Lahr]

My apologies Richard, but I do not see how your commentary relates to this
thread.  I mean this comment literally, as in, you will have to explain it
a bit further.

We never discussed molecular vs morphological, I do not understand how that
is relevant here. We are also not discussing species relationships, but
deep lineages.  Additionally, I do not see a connection between your
interpretations of ancestor-descendant relationship scenarios and
phylogenetic resolution. In my view, both cases you have pointed out only
indicate error in the initial naming, ie, if a genus nests within another,
this means renaming is necessary.  This does not indicate a general flaw
with the reconstruction method.

Dan

On Mon, Mar 18, 2013 at 7:39 PM, Richard Zander <Richard.Zander at mobot.org>wrote:

>
>
> Not objective? The fundamental phylogenetic presupposition that of any
> three species two are more closely related fails totally in two cases:
>
> 1) paraphyly, including nesting of genera among species of other genera.
>
> 2) when any one generalist, wide-ranging extant species can be easily
> hypothesized as ancestral to one or more derived, highly specialized,
> and possibly evolutionarily dead-end descendant species.
>
> Both cases are common. Ergo phylogenetic resolution of branch order is
> commonly random in both morphological and molecular analyses. This is
> not even subjective much less objective.
>
>
> ____________________________
> Richard H. Zander
> Missouri Botanical Garden, PO Box 299, St. Louis, MO 63166-0299 USA
> Web sites: http://www.mobot.org/plantscience/resbot/ and
> http://www.mobot.org/plantscience/bfna/bfnamenu.htm
> Modern Evolutionary Systematics Web site:
> http://www.mobot.org/plantscience/resbot/21EvSy.htm
> UPS and FedExpr -  MBG, 4344 Shaw Blvd, St. Louis 63110 USA
>
> -----Original Message-----
> From: taxacom-bounces at mailman.nhm.ku.edu
> [mailto:taxacom-bounces at mailman.nhm.ku.edu] On Behalf Of Dan Lahr
> Sent: Monday, March 18, 2013 4:22 PM
> To: Ken Kinman
> Cc: taxacom at mailman.nhm.ku.edu
> Subject: Re: [Taxacom] Cyanoprokaryota help
>
> Hi Ken,
>
> I am familiar with your views on strictly monophyletic classifications.
> I personally find the discussion constructive for science.  However, I
> have not been convinced that allowing paraphyletic classifications is a
> good solution, but this is not the place to go into the gritty details.
> Therefore, I stick to the general convention of naming exclusively
> monophyletic entities.
>
> Dividing life into Prokaryota and Eukaryota is unsatisfactory, because
> these are grades and do not lead to any objectivity, and do not reflect
> things we know about the true nature of the critters.
>
> There may surely be a possibility that the root of life is within
> bacteria, which would make eukaryotes and archaea simply branches on the
> bacterial tree.  If so, then a lot of bacterial groups would need to be
> renamed, because our understanding of the true diversity will remain
> restrictive and flawed if we do not change the names.
>
> The system allows relabeling when relabeling is needed.  The Woesian
> revolution has shown that relabeling was needed, and relabeling ensued.
>
> Dan
>
>
> _______________________________________________
> Taxacom Mailing List
> Taxacom at mailman.nhm.ku.edu
> http://mailman.nhm.ku.edu/mailman/listinfo/taxacom
>
> The Taxacom Archive back to 1992 may be searched with either of these
> methods:
>
> (1) by visiting http://taxacom.markmail.org
>
> (2) a Google search specified as:  site:
> mailman.nhm.ku.edu/pipermail/taxacom  your search terms here
>
> Celebrating 26 years of Taxacom in 2013.
>



-- 
___________________
Daniel J. G. Lahr, PhD
Assist. Prof., Dept of Zoology,
Univ. of Sao Paulo, Brazil
+ 55 (11) 3091 0948