[Taxacom] Order Campanulales (worth maintaining?)

[Richard Zander]

I think macroevolution is a major area of theoretic discussion. This includes origin and evolution of genera and higher taxa, as well as origin of species. Check works by Gould and Vrba for lots of theory of evolution of groups of species. 
 
Species are special in being the basic units of taxonomy. On the other hand, genera are real groups. I've suggested right here on Taxacom that the common plaint that there is no genetic exchange between species of a genus and therefore no possible "generication" is based on a simple population biology concept of speciation, only one of many ways to speciate. Thus, the environment (I hypothesize) may provide the "envirosome" as a shared "metagenetic" element that forces (through natural selection among species) all species of a genus (that are exposed to a particular selective regime, and many are) toward some different selective regime. Thus, genera evolve. Ditto families. 
 
Demonstrate to me why I am wrong, you who disagree enough to say so, and not by mapping traits onto a cladogram or ad hoc axioms. That is not science.
 
[I suggest that exchanges like these demonstrate the health of taxonomy, however parlous it may seem financially.]
_______________________
Richard H. Zander
Missouri Botanical Garden
PO Box 299
St. Louis, MO 63166 U.S.A.
richard.zander at mobot.org
 

________________________________

From: taxacom-bounces at mailman.nhm.ku.edu on behalf of Curtis Clark
Sent: Fri 2/18/2011 9:21 AM
To: taxacom at mailman.nhm.ku.edu
Subject: Re: [Taxacom] Order Campanulales (worth maintaining?)



On 2011-02-18 04:07, Rob Smissen wrote:
> Just so we are all on the same wavelength, please remind us, uh, Curtis, why is it that species are special (without recourse to "genus concepts", "family concepts", or species concepts).
It is widely held that species are special; there is even a branch of
evolutionary study, "speciation", devoted to their origin. I happen to
agree with that proposition, but certainly not everyone does.
Nevertheless, I'm not aware of similar fields of "generication",
"varietization", and "familiation", and "ordination" is used in several
very different senses.