Cabin fever antidote

J.E. Shields
Fri, 23 Jan 2004 15:51:50 PST
Jim McK.,

Good idea!  The weather here is definitely not conducive to outdoor 
activities -- too cold and too windy.  Sorry, Diane.  Back to the keyboard.

1.  A Geophyte is whatever we define it to be.  I define the concept very 
broadly:  A plant having some sort of subterranean storage organ and an 
herbaceous, perennial habit.  Since I'm not a taxonomist, you can take my 
"definition" with a grain of salt.  (I've noticed that some real 
taxonomists in the past have used conflicting concepts as invitations to war.)

I think the usual definition, limiting "geophytes" to bulbs, corms, tubers, 
or rhizomes, is a bit narrow.  Jim Waddick's Paeonia, some of Mary Sue's 
Delphinium, lots of things with "fat" roots, surely ought to be 
included.  I like to say something like, "geophytes and friends" for 
suitable discussion topics.  The term "geophyte" is, after all, not a 
phylogenetic classification but a pragmatic one.

2.  Species are human conceptual constructs too, by and large.  Those 
obvious species, easily perceived, are not the problems of course.

For a lot of biologists, I suspect the true but unspoken definition is 
something like "I can't actually define species, but I know one when I see 
one."  There are a few, like Pierre Felice Ravenna, who see new species 
wherever they look.  There may be matters of ego gratification involved, or 
more serious motivations like getting tenure or a promotion.  All sorts of 
things can help define "species."

The definition that goes something like "a species is an interbreeding 
population" bothers most people, who seem to read into it the word 
"potentially"; i.e., "a species is a [potentially] interbreeding 
population" which confuses the devil out of things where plants are 
concerned.  The orchids present an obvious case in point, with myriads of 
complex, multiply (adverb of "multiple") intergeneric hybrids made in 
cultivation.  Remember:  where species are concerned, cultivation does not 
count!  I like the approach that starts with a species as an identifiable 
group of individuals, sharing certain traits in common.  You can elaborate 
from there.

This also opens up the notion of reticulated evolution, or interspecific, 
possibly intergeneric, even inter-kingdom transfers of genetic 
material.  For instance, the human genome is full of relict viruses.  How 
do you want to handle that?  This just shows how far Mother Nature will go 
to frustrate human attempts to organize things into neat pigeonholes.

Jim Shields (a.k.a. Jim S; i.e., not Jim W and not Jim McK)
in central Indiana (USA)

At 05:00 PM 1/23/2004 -0500, you wrote:
>I'm bored! Let's get some good fights going here! Let's start some threads
>on 1) the definition of geophyte and 2) species concept.
>To start, I'll stick my neck out and offer these (perhaps outrageous)
>1) with respect to geophytes, not all bulbs are geophytes
>2) with respect to species concept, living things don't exist as species,
>they just exist
>Fire up your blazing keyboards!
>Jim McKenney

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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