Christmas Bells

Christmas Bells
Christmas Bells - Blandfordia nobilis

Tuesday, August 12, 2008

What's in a Name?


"What's in a name? That which we call a rose
By any other name would smell as sweet."

Romeo and Juliet (II, ii, 1-2)

Unfortunately, the Bard was not aware of the existence of Greenhood Orchids (which name he would have liked). But I confidently predict he would have hated the generic name Pterostylis.

The reason I have followed this line of argument is because I was challenged last week by an experienced Orchid observer to justify why I had written in the local REPS Magazine "Eucryphia" about Pterostylis hildae - when in the opinion of this gentleman, I was simply writing about the much more common Pterostylis curta.

Pterostylis hildae (left) - Pterostylis curta (right) - front view
Note the twisted labellum of Pt. curta,
and the honey-coloured "galea"(hood) of Pt. hildae.

I started to say its leaves were smaller than Pt. curta, and the tongue of curta is always twisted to one side. These "minute" differences were dismissed as insignificant (somewhat annoyingly, I admit, but I like and respect, my interrogator, and do not wish to offend him.)

Ultimately, my defence rested upon what was simply an "Argument by Authority" (as it was called in my Philosophy classes). I cited my favourite Orchid Expert, David Jones. His book: "A complete guide to the Native Orchids of Australia, including the Island Territories" is the most comprehensive
book about Australian Orchids which I know of.

Quickly the gentleman replied that he could buy another book which would not agree with my expert. True enough. But I ask, would his book be as "authoritative" as mine? Who can "settle" that argument?

Pterostylis hildae (left) - Pterostylis curta (right) - side view
The conversation then headed towards a discussion of the merits of "Lumpers" versus "Splitters". This is a familiar argument, much loved by conservative naturalists who hate "change" and "unfamiliar names". If you dislike the new names, disparage the authority as a "splitter". Of course, I acknowledge there are contrary arguments based upon individual variations in nature, and the readiness of some people to proclaim a "new species" based upon very small sample sizes. This debate is endless.

Lumpers and splitters: "Different taxonomists take different approaches about whether small differences in appearance should form the basis for new species or not. When lists are compared, those produced by lumpers will contain fewer species and will appear similar. This will lead to a conclusion that the communities are relatively cosmopolitan. Lists made by splitters from the same communities will include more species and there will be less overlap. Comparison of these species lists may favour the conclusion that the dissimilarity of the communities is as a result of endemism." Source: Lee and Patterson - see point 3 "Lumpers and splitters" at hotlink above.

Ultimately this debate comes down to the consensus of experts, as to whether your "new species" is accepted by the scientific community. Another way to look at this is to ask how long has the species been accepted?

In the case of Pterostylis hildae, it has been around for a long time, for it was named by famous Orchidologist, William Henry Nicholls (1881 - 1959). It is not one of the "new names" created by David Jones and Mark Clements. (That would not worry me - but clearly it would worry my debating colleague) It is also accepted by the conservative botanists at the Royal Botanic Gardens (Sydney) and their PlantNET on-line reference.

In my opinion, Pterostylis hildae is a "good" species.


Mosura said...

I'm in no position to opine om the matter, however, your excellent photos illustrate this post very well.

Denis Wilson said...

Thanks Mosura.
Well, one can see obvious similarities, but to me, there are obvious differences too. That's the point.

Duncan said...

Denis, I reckon the taxonomists just take a perverse delight in making things complicated. I reckon we should forget the botanical names and go back to using common names! I also think they keep changing names just to make us keep buying books to keep "up to date"!