Question about Naked Ladies

J.E. Shields
Fri, 21 Dec 2007 11:41:40 PST
Steve, Jim McK., Jane, and all,

I also encountered the term Rassenkreis first in regard to Lepidoptera, but 
specifically to the butterfly Junonia coenia, which also ranges from 
Florida across the central USA to Mexico and Central America.  It its case, 
I think there is at best very limited fertility between the Florida and the 
Central American forms, but with the same continuous fertility between 
neighboring populations.  Steve described the situation very well 
indeed.  I'm pretty fluent in German, but I also had to check the spelling 
before proceeding with my original posting.

I thank Jim McK. for reassuring me that cline is also applicable.  "Cline" 
might be more botanical, or it might be just a matter of years.  I 
encountered "Rassenkreis" at least 40 years ago.  It could easily have 
fallen by the wayside in that length of time, especially considering the 
degree of Anglicization of science in the intervening years.

Jane, I have not encountered "continuum" used in a biological sense 
before.   This probably shows how narrow my biology reading has been over 
the years.

Whether Jim's Lilium greyii/canadense situation is a cline or a localized 
intergradation between two young, mostly allopatric and closely related 
species is perhaps debatable.  I certainly don't know the situation with 

Where you have two mutually interfertile species existing in sympatric 
populations, if there is a barrier, they can be pretty stable.  Introducing 
the human element may be all that is needed to overcome such a barrier to 
interbreeding.  I can see where, over time, and intermediate population 
could take over or it could be extinguished.  If the parent species include 
individuals that are not fertile with members of the other species, they 
might prosper as the hybrids decrease.

Getting back to vernacular names, I'd say there are many things you simply 
cannot discuss using vernacular names.  On the other hand, the day is not 
far off when species, local populations, and individuals will be identified 
and defined by their DNA.  It's just the direction things are going and 
will continue to go, barring some Armageddon or other broad catastrophe.

Best wishes,
Jim Shields
in central Indiana (USA)

Jim Shields             USDA Zone 5             Shields Gardens, Ltd.
P.O. Box 92              WWW:
Westfield, Indiana 46074, USA
Tel. ++1-317-867-3344     or      toll-free 1-866-449-3344 in USA

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