Aff - able?

totototo@telus.net totototo@telus.net
Thu, 20 Mar 2008 10:02:54 PDT
On 18 Mar 08, at 20:23, Jim McKenney wrote:

> I object to the use of this term affinis in the way being discussed
> because it is illogical: it does not deliver what it promises. It
> purports to state the very things which are in fact unknown:
> relationship and identity. 
> 
> The word akin expresses natural relationship, not mere similarity.
> What sense does it make to use the word akin before such natural
> relationship is established? 
> 
> This distinction between natural relationship and mere similarity is
> the salient difference between modern taxonomy and taxonomy as
> practiced up until the beginning of the twentieth century. 

But Linnaeus was still cooking with gas when he pinpointed floral 
anatomy as the key to understanding relationships. If you look up 
from your computer and take a good gander out the window at the 
taxonomic landscape, you will see that most genera established using 
floral anatomy are still held to be valid.

Yes, there are problematic areas, the South American tangle of 
Ipheions, Nothoscordums, Beauverdias, and who knows what else being 
the one that comes to mind, but Mother Nature does have a fondness 
for playing jokes on scientists, so what else can we expect?

The place where DNA and other microscopic evidence is proving 
valuable is sorting out higher taxons, families in particular. We all 
know (or should) that there's a tangle involving peonies, 
podophyllums, jeffersonias, and such, and hopefully DNA is helping 
figure it out. But the generic boundaries remain largely untouched.

Thus, using aff, meaning roughly "looks a lot like", doesn't just 
mean that there's some kind of vague overall similarity, but that on 
close inspection, the critical features of floral anatomy (and other 
relevant details) are closely similar to previously named species.

I wrote earlier, and then again just above "looks a lot like" but to 
be precise the phrase should include "with reference to anatomical 
details indicative of taxonomic relationships." That's a little 
vague, but of course the details used in one class of plants may be 
different from those in another class.


-- 
Rodger Whitlock
Victoria, British Columbia, Canada
Maritime Zone 8, a cool Mediterranean climate

on beautiful Vancouver Island


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