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Re: ...and how ranks don't work in mnemonics



Anthony Docimo wrote various and sundry:

> Again, they don't.
>
> They pretend to, but they don't.

 No? Which are humans closer relatives to: *Gorilla gorilla* or
 *Catta catta* ?

The one that belongs, like we do, to Homininae, Hominidae, Hominoidea, Catarrhini, Anthropoidea, and Haplorhini.

What ranks any of these names have* is completely irrelevant.

I'm not arguing against having _names_ for clades. I'm arguing against having ranks for names.

* If any. Conventionally, there are only one or at most two ranks available -- suborder, infraorder -- for the three nested clades Haplorhini, Anthropoidea and Catarrhini. This gets even worse if you're a paleontologist who calls the primate crown-group Euprimates and uses the name Primates, ranked as an order all the way back to L. 1758, for a larger clade. ... Do you notice? Ranked nomenclature restricts the number of clades we're allowed to name. It forces us to make choices that have nothing whatsoever to do with science. It hinders communication.

 If you're trying to determine the number of (taxa/?) that are in a
 given plot of rainforest/reefs/other habitat, to convince that
 nation's government to set aside that area for conservation*, which
 do you think helps your effort more?

 -Ranks

 -Phylogenic tree (of taxa new to science?)

Phylogenetic trees with dated divergences. (Timetrees as they're now called.) If you tell someone as uneducated in biology as the average politician with a doctorate in law or economics "you've got two unique _orders_ in there!!!", you'll have to explain what an order is! And you can't, because there's no way to quantify it!

 aaaand the joke dies alone in the rain.

I know. It was a misleading joke, so I explained what I meant instead.

 wait...did you mean that each Cambrian "species" gets its own
 phylum?

Not only that. I said that every "+" _and_ every name in this tree

--+--Palaeoscolecida
  `--+--Onychophora
     `--+--"armored lobopods" if not paraphyletic!
        `--+--Tardigrada
           `--+--*Kerygmachela*
              `--+--Dinocarida if not paraphyletic!
                 `--+--Trilobita
                    |--Chelicerata
                    |--Myriapoda
                    `--Tetraconata/Pancrustacea

receives phylum rank. And keep in mind that the arthropod-sensu-stricto part of this tree is _grossly_ oversimplified, hiding a lot more divergences that all happened in the Cambrian, both between and within the four clades I show.

>> until trees get something as catchy as "King Philip can order
>> five great snakes" (or the astronomical equivilent, "oh be a fine
>> girl, kiss me"), the public may not catch on as fast as you
>> like.
>
> Are you saying that the general public does understand ranked
> nomenclature now, or at least know the ordering of kingdom,
> phylum, class, order, family, genus, species?

 they should - at least, every time I use the mnemonic for the
 ordering, everyone knows what I mean.

Because you explained it to them a few years ago?

I have never been taught any such mnemonic for the ranks, and I really don't think that's just because your particular one happens not to work in German.

Indeed, I've never been taught the ranks themselves! They were sort of mentioned in one middle-/highschool biology textbook, IIRC, but the teacher never got around to that part.

> I'm asking because that would be wildly at odds with my experience
> - near as I can tell, the avg nature documentary viewer neither
> knows nor cares whether a phylum is bigger or smaller than an
> order.

 we can simplify it, we can explain it...but at the end of the day,
 it's to to them whether or not they bother to pay attention.

In that case, we can as well teach trees and names on them instead of ranks.