[Taxacom] OMG! DNA only descriptions (with one habitus photo)!
fwelter at gwdg.de
Thu Aug 1 17:13:06 CDT 2019
> "Looking like fig. 1" is certainly an attribute of organisms
Not under the French Code. Such an interpretation of the term
"character" cannot be intended in the English Glossary.
In Code-5 we should align the English Glossary's definition for
"character" to that of the French Glossary's current definition, to read
"Any descriptive element of an organism used for recognizing,
differentiating, or classifying taxa. Vernacular names, localities,
geological horizons or hosts are not characters in the sense of this
"Looking like fig. 1" - even if this is regarded as a character - this
statement as such does not contain anything distinctive, which is
expressly demanded in Art. 13.1.1. "Looking like a figure" does not
differentiate a taxon. Which characters shown in the figure would
differentiate the species from others? Its colour? Its four legs? The
relative length of its ears compared to its head length? If the colour
is not regarded as important, a zebra may look like a horse.
515 T would only constitute a description if it was clear from the
context that other species would not have this character.
I agree with David in this point.
Am 01.08.2019 um 23:49 schrieb Stephen Thorpe via Taxacom:
>> "Looks like fig. 1" does not actually provide any diagnosis of what supposedly distinguishes the species.
> The glossary of the Code defines 'character' as 'Any attribute of organisms used for recognizing, differentiating, or classifying taxa'
> "Looking like fig. 1" is certainly an attribute of organisms, which can be used for recognizing, etc. The fact that it may fail to provide a transparent or even useful diagnosis is irrelevant to Code compliance.
> On Thursday, 1 August 2019, 09:34:21 pm UTC, David Campbell via Taxacom <taxacom at mailman.nhm.ku.edu> wrote:
> "Looks like fig. 1" does not actually provide any diagnosis of what
> supposedly distinguishes the species. Similarly, an 1840's description
> that I ran across that gives a detailed locality, but only describes it as
> "this fine species", does not actually give a valid description. Saying
> "this species has C instead of T at position 542" does give a purportedly
> distinctive feature; similarly, a paper from 1834 with mostly nude names
> that mentions the size of one species is considered the valid source of
> that name (conveniently, only one species credibly assignable to that genus
> reaches that size in that location). The latter two are quite
> unsatisfactory diagnoses from the viewpoint of systematics, but they do
> purport to distinguish the species in a way that "look at the picture"
> doesn't, and thus meet the letter of the law. Of course, the paper in
> question didn't just cite a single base pair difference; that's a
> hypothetical exaggeration.
> DNA can potentially be a good basis for naming species, but it takes
> significant sample sizes to verify what level of difference in what gene
> actually is distinctive in a particular group.
> On Thu, Aug 1, 2019 at 4:49 PM Stephen Thorpe via Taxacom <
> taxacom at mailman.nhm.ku.edu> wrote:
>> The problem with that approach, as I have already indicated, is that
>> something like just "Looks like fig.1" is a description/diagnosis in words.
>> Yet it has no more meaning than fig. 1 itself, so is equivalent to
>> description/diagnosis by illustration only, which is presumably what the
>> "in words" requirement is intended to rule out!
More information about the Taxacom