Clear and Present Evidence

Felix Sperling Felix.Sperling at
Tue Apr 4 14:45:42 EDT 2000

	I applaud you doing this!

	To plunge into following along with the line of logic that
you outlined, I wonder about your statement that there is zero evidence
of linking populations between the far northwest and the rest of the
continent, at least in the distribution maps of the Butterflies of
Canada. It looks to me like there is a real possibility that this
is a collecting artefact, at least for the part of the Peace River
that has appropriate grassy patches but is poorly collected where
it goes through Wood Buffalo Park in northern Alberta. The gaps
there are similar to the gaps in the Northwest Territories along
the Mackenzie River.

	Also, what about populations of Coenonympha going through
the Great Basin, especially areas like southern Idaho, which seem
to me to serve to connect "californica" populations on the Pacific
slope with "inornata" to the east? I'll bet there are plenty of
those, and treatments like Scott's book (which has plenty of
original observations in it) would qualify as giving you some
"published information" to counter your statement that californica
and inornata connections have not been documented in published form.

	This leads to an interesting philosophical point. When there
is obvious ambiguity in the published evidence, what should be the
default? I would argue that populations like this should be considered
to be part of the same species until there is substantive evidence
to show that they are different species, whether by evidence of
overlap without merging, or overall character differences in disjunct
populations that are similar to the extent of character differences
in most pairs of sister species that do contact each other. You appear
to be arguing that populations with small differences should be
considered to be different species until there is substantive
evidence that they are the same. Accepting your line of reasoning
for the moment, I would argue that you still need to demonstrate
that the populations are consistently diagnosable. In other words,
is there clear evidence that you can tell all individual specimens
apart without knowing where they are from?

	It seems to me that the whole situation with ringlets desperately
needs a careful reanalysis. One way would be to make a serious effort to
collect in geographically intervening areas. Another would be to look
at other characters (like Porter and Shapiro's work) to determine if the
slight and confusing wing pattern differences are just environmentally
selected characters that are only "skin deep", versus being
an indication of deeper genetic differences, where the wing pattern
differences are just the metaphorical tip of the iceberg. An example of
the former case would be our own species, since we have skin color
variation on a geographic scale in spite of a clearly very similar
underlying genome (I'm setting aside evidence of interbreeding or population
movement in recent historical time for now because, at the moment, I'm
not aware of equivalent information for Coenonympha). An example
of the latter case might be the Bonobo chimpanzees, which have only
recently been accepted as distinct species, since they look much like
the regular chimpanzees and it took some time to document that they
are behaviorally and genetically different at a very deep level.

	Felix Sperling

>This bears on the topic of evidence and taxonomic treatment with one or more
>options to select from.  A couple of recent books have used the species
>Coenonympha tullia to reference all western North American ringlets.  If a
>rationale for this was presented in either book, I was not able to find it.
>I am not aware of any published or unpublished information to support this
>interpretation/taxonomic decision.  In the course of picking a name (to
>apply to southern BC ringlets) for a report last year; I reviewed the
>published information that I have at hand and applied my version of logical
>thinking to come to a conclusion.  Here is what I wrote: "This species has
>been variously listed as C. tullia or C. ampelos in the literature.  My
>reasons for assigning the Pend-d'Oreille material to the species C.
>california are similar to deciding whether to use tullia or inornata during
>writing of Alberta Butterflies (Bird et al. 1995).  There appears to be no
>evidence to support the notion that C. tullia is present throughout the
>entire range of ringlets in North America.  A paper by Davenport (1941) is
>sometimes cited as evidence (most recently by Webster 1998) that we should
>call all our North American material tullia but this evidence seems to
>consist of a casual statement that the populations on the opposite sides of
>the Bering Strait "are hardly to be considered distinct".  It is noteworthy
>that Davenport plainly states "... I have purposely neglected to separate
>the Coenonympha of the New World from those of the Old...".  In fact,
>nothing has ever been published to connect these far northwestern
>populations with taxa such as inornata or ampelos.  In the case of southern
>BC, Porter and Geiger (1988) provide compelling evidence that the butterfly
>previously treated as the species ampelos is in fact correctly placed as a
>subspecies of C. california."
>I also looked at the distribution maps in Butterflies of Canada and saw that
>there is zero evidence of linking populations between the far northwest
>populations and the rest of the continent.  I have also not seen any
>published evidence that inornata grades into the group of taxa which appear
>to be best treated as C. california. So on the basis of published evidence I
>conclude that the ringlets in southern BC are best called C. california and
>those in Alberta are best called C. inornata
>Of course I would be interested in the rationale for other treatments and
>because I chose to not limit my decision making by only looking at part of
>the available evidence; I would also welcome any info/observations on this
>topic which have not been published.
>And last but not least; bonus points for those of you who correctly
>recognized the title of this note as a play on words derived from the movie
>"clear and present danger" starring Harrison Ford :-)
>Norbert Kondla  P.Biol., RPBio.
>Forest Ecosystem Specialist, Ministry of Environment
>845 Columbia Avenue, Castlegar, British Columbia V1N 1H3
>Phone 250-365-8610
>Mailto:Norbert.Kondla at

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