Jean-Marc Vanel wrote under the Subject:
RDF Schema design pb: inheritance of properties
(Subject renamed, because this post refers to
issues secondary to the original post)
> There is a containment hierarchy (e. g. a flower contains petals)
which
> raises no problems in XML.
I would like to challenge this assumption, which seems to be
generally accepted in the discussion here.
It is true: Morphological structures may have containment
hierarchies, but I believe that these depent strongly on the
viewpoint of the author or user.
EXAMPLE 1: The peduncle (stalk of a flower) is usually assumed to be
part of the flower, but anatomically it is clearly a part of the stem
(in contrast to the petiole, stalk of a leaf!).
EXAMPLE 2: Stuff can be in-between: The inflorescence contains part
of stem, part of leaves, and all flowers. Which leaves are part of
inflorescens and thus called bracts, and which aren't is often a
matter of taste, school, country...
Thus: there are multiple concurrent or competing hierarchies, which
may overlap.
EXAMPLE 3: Further, other, non-morphological
hierarchies/classifications exist. These may be much more relevant
for many purposes, and may be the primary outline used in a natural
language description. For example, structures can be classified by
function (sexual/asexual propagation), observation method (naked
eye/light microsc./electron microscopy, physiological/molecular etc.
EXAMPLE 3 (leaving morphology altogether): Gene sequences can be
classified as transscribed/non-transscribed, Protein-coding/rRNA
coding/non-coding, intron/exon, regulatory/structural,
conserved/variable/hypervariable etc. Most of these classifications
overlap.
*** Call for more examples: Can anybody come up with more good
examples (perhaps from animals) as to why a fixed hierarchy in the
form of a feature path may be unpractical?
> Info. for computer men: biology has a hierarchic classification of
> species whose 4 lowest levels are:
> order
> family
> genus
> species
Sorry this is a gross misrepresentation. Info from a biologist:
(incomplete list, reflecting botanical code, and devised with fungi
in mind). Number of ranks is a matter of taste, some people like to
supra and sub [and hyper+hypo? :-) ] everything:
CODE Description
fsp. forma specialis nov. -- nomenclatorially facultative
subfm. subforma nov. -- subform nomenclatorially obligatory
fm. forma nov. -- form nomenclatorially obligatory
subvar. subvarietas nov. -- sub-variety nomenclat. obligatory
var. varietas nov. variety nomenclatorially obligatory
ssp. subspecies nov. subspecies priority mandatory
sp. species nov. -- species priority mandatory
subser. subseries nov. -- subseries priority mandatory
ser. series nov. -- section priority mandatory
subsect. subsectio nov. -- subsection priority mandatory
sect. sectio nov. -- section priority mandatory
subgen. subgenus nov. -- subgenus priority mandatory
gen. genus nov. -- genus priority mandatory
subtrib. subtribus nov. -- subtribus priority mandatory
trib. tribus nov. -- tribus priority mandatory
subfam. subfamilia nov. -- subfamily priority mandatory
fam. familia nov. -- family priority mandatory
superfam. superfamilia nov. -- super-family priority mandatory
subord. subordo nov. -- suborder priority facultative
ord. ordo nov. -- order priority facultative
superord. superordo nov. -- superorder priority facultative
subclass. subclassis nov. -- subclass priority facultative
class. classis nov. -- class priority facultative
subdiv. subdivisio nov. -- subdivision priority facultative
div. divisio nov. -- division priority facultative
subreg. subregnum novum. -- sub-regnum priority facultative
reg. regnum novum. -- regnum priority facultative
Gregor
----------------------------------------------------------
Gregor Hagedorn G.Hagedorn(a)bba.de
Institute for Plant Virology, Microbiology, and Biosafety
Federal Research Center for Agriculture and Forestry (BBA)
Koenigin-Luise-Str. 19 Tel: +49-30-8304-2220
14195 Berlin, Germany Fax: +49-30-8304-2203
Often wrong but never in doubt!
