Species of hybrid origin -"amateur" treatment and taxonomy

Ken Hixson kennethhixson@gmail.com
Wed, 16 Jun 2010 09:32:19 PDT
     I hear a desire for information
>> here from some participants in this forum.  Shall it be addressed?  and How?
>> Outsource these folks to a college level course?  A high school level
>> course?

>>> Dear Friends,
>>> Although I have vaguely followed the discussion, there is an
>>> air of blind leading blind.
>>> I don't even know where to start here, but do read something
>>> relatively factual instead of making guesses and going off on
>>> tangents.

     Is there confusion here?  Yes there is.  Astonishing as it may 
seem, botanists do not
all think the same thing.  There are "lumpers" and there are 
"splitters", and their opinions
are very different, given the same set of facts.  Some botanists believe 
that a "hybrid" is
defined as any cross between two plants of different genetic 
characteristics.  This might
be considered the "splitter" definition of a hybrid.  It brings up the 
interesting situation
of many plants which must cross with a different plant to produce seed.  
Consider the
"English" holly, Ilex aquifolium. Some plants are functionally female, 
and bear berries.
Others are functionally male, produce pollen but no berries.  By the 
"splitter" definition
of a hybrid, all seed grown members of the species Ilex aquifolium, are 
a hybrid, even
though they are pure species Ilex aquifolium.  The list of examples 
could be extended
greatly, because in fact many or most species of plants are more fertile 
if "outcrossed" to
some other plant of the same species.  There are numerous ways the 
"outcrossing" can
be achieved, not only having male and female plants, but having pollen 
produced before
the stigma is receptive, or the stigma being taller than the anthers, etc.

     To me, this "splitter" definition of a hybrid is nonsensical, as 
most plants under this
definiton are both a species and a hybrid.  To me, they should be one or 
the other,
not both.  Well, I'm not a botanist.  Confusion exists, and I've seen 
plants being
exhibited in shows, which were disqualified as the exhibit in question 
had been grown
from seed by the exhibitor, who had hand pollenated the mother plant and 
then protected
the cross to prevent cross pollenation.  However, the judge knew that 
the species being
exhibited was self incompatible, so "it had to be a hybrid".  How the 
judge thought the
species had survived in it's native habitat without being cross 
pollenated for many
centuries, I leave for you to figure out.  The exhibitor, naturally, was 
furious, and to
the best of my knowledge never again bothered to show flowers to that group.
Who do you think lost the most by the actions/opinions of this judge?

     Are there factual differences between botanical "lumpers" and 
Not necessarily, but there are different opinions between them, and even 
differences between the way botanists and the general public understands 
terms, and confusion can only be reduced if we talk about what the 
differences are.


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