Latin names versus scientific names [was: So much for nomenclatural stability]

[Curtis Clark]

on 2005-03-10 19:26 Thomas Lammers wrote:
> It's monothetic in the sense that only one sort of information,
> branching pattern inferred from synapomorphies, is the entire basis
> of the classification.

I have to say that this sounds like historical revisionism. Groups such
as the mammals and angiosperms have always been classified by
synapomorphies, whether we understood them or not. The "boundaries"
between Verbenaceae and Lamiaceae, Araliaceae and Apiaceae, Fumariaceae
and Papaveraceae, and Capparaceae and Brassicaceae were always
problematic and tantalizing, even before we realized that in each case
the former was paraphyletic by removal of the latter.

To castigate the preference for synapomorphy simply because there is a
rationale behind it strikes *me* as antithetical to good science.

And keep well in mind that every paraphyletic group can be specified by
Boolean operations on clades, and therefore paraphyletic groups *are
also diagnosed by synapomorphy*. (A symplesiomorphy is simply a
synapomorphy turned upside down, and every other character is a
homoplasy. I'm sure you don't advocate classification by homoplasy.)

> I have the unenviable task now of explaining to my into botany
> students why their textbook says Psilotum and Equisetum are ferns,
> but lycophytes aren't.

I learned this back in the 1970s well before I "became a cladist".
Although the fossil evidence didn't suggest that Psilotum was as close
to ferns as the DNA does, the lycophyte split has been known for decades.

> I have to explain that there's "no such
> thing" as a seedless vascular plant any more, despite six generations
> of botanists finding that a useful content.

It seems to me you're going overboard to be contrarian. "Seedless
vascular plant" is obviously all those vascular plants that are not seed
plants. Just because we don't name it in formal taxonomy doesn't make it
useless. I still use the term "dicots" to refer to non-monocot
angiosperms. The only people that object to that sort of thing are
members of the Committee for the Classification of Straw Men.

> I have to explain to
> them that an orchid or a grass is "more closely related" to a fern or
> horsetail (they are all megaphyllous Euphyllophytes, despite
> Equisetum having what everyone has called microphylls for years) than
> ferns and horsetails are to the lycophytes that share the same life
> cycle.

But what about the lycophytes that share the heterosporous life cycle?
And what about mosses and liverworts that share the homosporous life
cycle with ferns?

> They look at me like I'm stupid when I explain that to them.
> They actually ask, "What sense does THAT make, Dr. Lammers?"   Out of
> the mouth of babes ...

My students have no trouble understanding the sense of it. I can't
imagine that the student population at my institution is all that much
brighter than at yours.

> Yes, I know this is heresy.  I know the systematics community has
> sold its soul to cladistics.

This is propaganda. I'm sure similar things were said about binomials
and evolution. Not all new innovations are necessarily good, but "sold
its soul" presupposes that most systematists are dupes.

> I'll probably never amount to a hill of
> beans professionally because of my refusal to kowtow before the altar
> of cladistics.

I haven't amounted to a hill of beans professionally, and I'm a flaming
cladist (although I don't remember the kowtowing part). Draw your own
conclusions.

> Any time that Playing By The Rules And Getting Nice
> Patterns is more important than finding out what's really going on,
> we aren't doing science any more, we're playing silly games.

And so you're back to throwing insults again. I deserve it, since I've
insulted you in the past, but there are a lot of systematists who are
using cladistics *and* finding out what is going on, and if they are
amounting to anything professionally, it's because they deserve it, and
all your grousing demeans you more than it does them.

> And did it ever occur that to anyone that "common misconception" just
> might mean "fact that people are too stubborn to accept"?

Tom, we're talking about the definition of a word here, not a fact. I
learned "monothetic" from the likes of Davis and Heywood, and although
we each seem to have come away with a different meaning, I think I have
adequately demonstrated above that the same characters are used to
support both paraphyletic and monophyletic groups, they are just used in
different ways.

--
Curtis Clark                  http://www.csupomona.edu/~jcclark/
Web Coordinator, Cal Poly Pomona                 +1 909 979 6371
Professor, Biological Sciences                   +1 909 869 4062