subspeciation & ecotypes

[Ron Gatrelle]

Open discussion

Chris Durden wrote.
Now where subspecies overlap it is often possible to assign syntopic
individuals to one subspecies or the other. These are ecotypes at this
locality. Because of slight differences of ecology we can think of all
subspecies as ecotypes.

Ron.
Chris, your use of the word _syntopic_  makes me think that what you are
actually talking about are _ecotopic_  populations, which are not to be
confused with an ecotype. An ecotopic population is a _taxa_ associated
with a certain ecology - as a swamp or a xeric area. An ecotype is a
_morph_ produced by the ecology. And ecotype is akin to wet/dry seasonal
forms - where the form is simply produced by the environmental conditions.
Usually, humidity, heat, or lack of these. If all one has to do to change
the morph is change the humidity and thermostat, it is not a subspecies -
period. The following have no ICZN taxonomic status: variation, form,
aberration, ecotype, and a few other terms. Why? Because they are not a
genetically stable, long term product, of biogeographic evolution.

It is impossible for two subspecies to exist at the same time and place.
multiple forms, yes. Subspecies, no. What you are calling two subspecies at
the same spot are just two forms.

Subspecies are definable evolutionary units - independent of their current
environment. (Put a heard of camels in a southeastern US wetland, and
outside of developing athletes foot, a hundred years later they will still
be camels. Then put their offspring back into the desert and they will
retain water for the long hall just fine.) There are many populations that
are not assignable to any sub-species. It is like this. Think of ocean salt
water as one subspecies and fresh river water as another water subspecies.
Where they "meet" is actually an overlap. Of course, this is what we call
brackish water. It is not salt water (though it is salty), and it is not
fresh water ( though fresh water is a major percent of its composition).
Now, depending on the time of day and tides, it may be more salty or more
fresh - but it is never salt water and it is never fresh water.

Here is another way to look at it. Subspecies are analogous to purebreds.
One may find a dog that "looks" like a pure whatever, but if it doesn't
have papers be careful. For when it is bread, oops. It looked like a pure
whatever but it was just a mongrel. A specimen from someplace which "looks"
like some subspecies from somewhere else is not that subspecies just
because of the way it looks. As A. B. Klots once said, to view subspecies
this way contravenes everything that is known of systematic taxonomy.

I just made a search of about 20 butterfly books and only one had the word
ecotype in its glossary. I Found that interesting an unfortunate.

Volley, and lob
Ron

PS Perhaps ecotype, as a term,  is being taught differently than the way I
learned it from my mentors, C.F. dosPassos, Clench, Klots, etc.


 
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