In defense of lumping :-)

[Kenelm Philip]

'Lumpers' have drawn a bit of flak recently on this list. It's been said
that taxonomic splitters are people with an eye for differences, while
lumpers are those with an eye for similarities. There is room for both
in the system...

	Here's a case in point. When I arrived in Alaska (1965) there was
a taxon _Colias nastes thula_ Hovanitz, described from Meade River on the
North Slope. I began finding this beast all over northern and western
Alaska, flying with _nastes_, which indicated that, whatever it was, it
wasn't a geographic race of _nastes_. Meanwhile, there was a Canadian
_Colias_, _C. boothii_, which flies in arctic Canada (and was considered
by some to be a hybrid between _nastes_ and _hecla_. Oddly, _boothii_
and _thula_ flew in similar habitats and at the same time (early summer).
_C. boothii_, a highly variable species, was basically orange in color,
while _thula_ is green (but also rather variable across its range).

	It was clear that _thula_ was not conspecific with _nastes_. It
was also _possible_ that _thula_ and _boothii_ were the eastern and western
populations of one species. That idea looked more plausible after I ran
into an odd green _Colias_ on Victoria Island that bore the same relation
to Alaskan _thula_ that _boothii_ from the Boothia Peninsula did to
_boothii_ from more southern sites like Baker Lake.

	Meanwhile, in Europe there was _Colias nastes werdandi_, from the
Fennoscandian arctic--which runs very close to _thula_. I and some of my
colleagues with arctic interests had been wondering whether _werdandi_
was really something in the _thula/boothii_ complex and not _nastes_ at
all.

	So, it was interesting to find that all these taxa have now been
lumped into _Colias tyche_ (a Eurasian species) by Europeans with Holarctic
interests. A number of other Eurasian 'species' have also been included.
That makes a very satisfying picture (to the mind of a lumper, at any rate),
and provides an underlying organization for what had been a rather messy
situation, taxonomically.

	The original names are all still available (as subspecies) should
anyone wish to use them. But I find the contemplation of a single pan-arctic
species more satisfying than an allopatric array of taxa originally listed
(variously) as subspecies of _nastes_ or as hybrids between _nastes_ and
_hecla_. Future work may change this picture--but I see nothing inherently
wrong with the underlying concept as long as it stands up. Lumping ipso
facto need not be feared...

							 Ken Philip
fnkwp at uaf.edu

P.S. Hovanitz came to Fairbanks, and I showed him series of _thula_ and
_nastes_ from the same locality. He insisted that _thula_ was nonetheless
a ssp. of _nastes_. A different concept of subspecies from what I was
taught, apparently.




 
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