Hi Tweets,

I thought this might be of interest, considering the sporadic discussions re
lumping and splitting. It was written by Wim Vader of the Tromso Museum in
Norway.

M


> TAXONOMY IS A FREE ENTERPRISE
>
> I have been a subscriber to several bird lists for some years now.
>Regularly questions of taxonomy and nomenclature crop up, most recently on
>EBN, after Dutch Birding has announced sweeping changes in the European
>list of bird species, as the result of rigid adherence to the Phylogenetic
>Species definition.Thios is an extreme case, but the same uncertainty is
>behind questions of the type: "What is the right genus name for .....?
>(Different books have different names)", or: "Are the Black Scoter and
>Common Scoter the same species or two different ones?"
>
> As a taxonomist, albeit it of amphipods rather than birds, I have read the
>recurring discussions about what species definition to use, and which
>committee has the right to decide such things, with increasing incredulity.
>In my opinion, problematic though that undoubtedly may be for all listers
>and other users, no committee, even of the finest taxonomists of today,
>will be able (should be able) to decide anything binding on species
>definitions, or on which genus name to use. I`ll try to explain why I am so
>adamant about this.
>
> In taxonomy, as in life generally, there have always been "splitters" and
>"lumpers". The splitters are most impressed by the differences between
>entities, and they therefore advocate small taxonomic entities and tend to
>make more species, more and narrower genera etc. The lumpers are more
>impressed by similarities than by differences, and they will always prefer
>larger species and fewer, broader genera.
>
>On the genus level a good example is the genus Anas for all the dabbling
>ducks: early splitters have coined a lot of other genus names (Mareca,
>Spatula,etc.), but in the last decades all dabbling ducks have been called
>Anas (I expect a reaction soon). At the species level, the Scoters form a
>good example: they are divided in 3, 5 or 6 species.
>
> There is fashion in taxonomy as there is other places in life: in some
>periods the splitters are in fashion, in others the lumpers, and here as
>elsewhere the children usually rebel against their parents, so that some
>sort of pendulum movement results. Just now the pendulum is swinging from
>an ascendancy of lumpers to a dominance of splitters: many genera are
>broken up into smaller entities (See e.g. Larus, Parus), and the trend is
>also to split up species into several smaller taxa. The theoretical
>background this time is the phylogenetic species concept(i.e. one of the
>several PSCs in the running),-- and I must say that I am personally quite
>impressed by many of the arguments of this school.
>But it is the same old pendulum swinging inexorably from splitters to
>lumpers and back again, of course superimposed on an ever-increasing
>detailed knowledge of the field and an ever-growing number of described taxa.
>
>So who is right and who can decide? It would be certainly great to have a
>list of names that everybody has to keep to; now the birdlists are full
>with questions as to whether the Silver Gull of Australia and the
>Red-billed Gull of New Zealand are the same species or not. And what to do
>with the sweeping revisions that the Dutch Birding Committee had proposed,
>and that result in many more countable species in Europe; are they right or
>are they wrong?
> To such questions IMHO there IS no correct answer; every taxonomist is
>free to apply his or her own species definition, with the resulting changes
>in nomenclature, and no official body or committee can regulate this,
>neither AOU nor Dutch Birding.
>
>This "fact of life" (Grandly called the freedom of science) is
>self-evident for the small group of scientists toiling with the taxonomy of
>amphipods, and the differences between individuals and schools of thought
>constantly generate a lot of heat and not rarely also some light. But it
>seems to be a very difficult concept for birders to grasp, primarily I
>think because it would be so practical, nice and reassuring to have a
>stable, all-accepted list of birds, that everybody could follow. IT WILL
>NEVER HAPPEN! (And this is an advantage, from the scientific point of view).
>
>Of course stability is a great good, and in communicating it is very
>important to ensure that one does mean the same when using the same name.
>Therefore the different ornithological and birding societies all have
>guidelines and official lists to which they keep in their publications, and
>to which listers have to keep in order to have their totals compatible. But
>such lists can never constrain science! There is no right and wrong in most
>of these questions; there are only different opinions!! That is often
>infuriating in many ways, but it is not a pity! It is the way science
>progresses!