Taxonomic Changes

Mary Sue Ittner
Tue, 01 Jul 2003 09:40:14 PDT
Dear All,

Yesterday I got my IBSA (Indigenous Bulb Association of South Africa) Bulb 
Chat #36 which I always find fascinating. This issue is a collaborative one 
so I don't know if the article below was written by Alan Horstmann, the 
current editor, or Andries de Villiers, the previous one. I'd suspect 
Andries, but it doesn't have his name on it so I could be wrong. Perhaps 
Rachel could help me to give credit where it is due. I don't see a 
copyright anywhere so I hope it is o.k. to   include this with the source 

Background: A couple of years ago the Manning-Goldblatt team reduced 
Homeria, Gynandriris, Hexaglottis, and Galaxia into Moraea, an already 
large genus. The IBSA members were especially unhappy about Galaxia as it 
more than any other of the disappearing genera resembled Moraea the least. 
There were protests and editorial comments. It is perhaps because of this 
that in the new Color Encyclopedia although all these are now listed under 
Moraea the key in the back of the book divides them into subgroups by the 
former genera. Although the article below may still be a bit too scientific 
for some of us gardener types I thought there are members of this group who 
are also unhappy with some of the changes who would appreciate it, so am 
copying it below as written in BULB CHAT.

Mary Sue


We are living through a revolution. For 250 years we have been loyal to the 
Linnaean concept of cognate species grouped together into genera. A genus 
comprising those species which shared a common or several common 
characteristics based primarily on a set of morphological characteristics 
could be described and defined to distinguish it from any other genus. In 
comparatively recent years a genus could be drawn as a cladogram to 
demonstrate the mutations that must have occurred in the course of 
evolution to produce the separate species. It was a tidy, logical and 
understandable progression not interrupted by specimens of other genera. 
Now we are being subjected to a taxonomy based on DNA analysis, a science 
still in its infancy, which discards morphology as the determinant of 
relationship and substitutes genetic proximity. We in IBSA were first 
subjected to it by the revision of the genus Moraea which sunk the genus 
Galaxia into the middle of Moraea. None of us liked it but few of us 
realized the implications. Now if we were to draw a diagram of relationship 
we would have to extend a straight line or several straight lines along 
which species of different genera are interspersed.  We would be creating a 
complex but, unlike a genus, the component species would have no common 
identifiable characteristics. Such a complex could not be defined. Genus 
was an inclusive concept, the component species all and only those which 
shared the determining characteristics. A DNA complex would include many 
components which had diverse characteristics and, moreover, would separate 
similar species by utterly different ones. When DNA taxonomy is applied to 
Lachenalia, Polyxena and who knows what else we will find various 
Lachenalia and Polyxena mixed helter skelter along the lines of relationship.

We need to remember one of the abiding features of a revolution. The 
generation which begins it is not the generation which refines and 
developes it. A younger generation takes over and introduces new and 
exciting applications. At present the Botanists who are leading the 
revolution are still imbued with the Linnaean concept and will try to apply 
generic names to non generic complexes. They will try to make definitions 
of disparate specimens. No doubt a new generation will devise a taxonomy to 
take care of it all but it is doubtful whether any of us will live to see 
it. Meanwhile we must stick to names that we can understand. To us a 
Galaxia is still a Galaxia."

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