I saw this in:
Minutes of the Subgroup "Structure of descriptive data" workshop at TDWG 1999 in Harvard
Diederich's "Basic properties" General agreement was reached that a direct application of the
"structure-property-value" model would be too restrictive, applicable mainly to morphological descriptions. A more general model, including cultural/physiological and molecular descriptions should be developed. The term "feature" was proposed as a more general replacement for structure.
This feature-property-value triology is what I had in mind the first time I read about Delta. A few remarks:
1. the feature can be a hierarchy, like:
leaf/lamina/abaxial_surface/vein_islands/indumentum/density
* the property can default to an "unnamed property", that is a textual content for the feature as a whole; this allows to import directly floristic descriptions, see http://jmvanel.free.fr/Samples/parsing.htm; * we can turn the Flora of Australia GLOSSARY in a XML vocabulary in XML Schema or RDF Schema syntax; each glossary entry should be classified either as a feature, or a property, or a property-value; * the current characters of Delta are in fact feature-property couples; * the current type of characters of Delta (multistate=enumerate, integer, real numeric, text) will become type information for properties in our new Taxonomic XML Schema; there is a standard for data types in the 2nd part of W3C's XML Schema recommandation; we must avoid to re-invent the wheel; * the proposed XDELTA format (http://www.bath.ac.uk/~ccslrd/delta/) is too much a direct translation of a Delta file; * I propose to have 3 XML Namespaces for our different XML vocabularies: o biological descriptions (generalities) o botany o zoology * XML Namespaces are important to avoid name clashes, they will allow us to mix in descriptions or reports with other vocabularies from other origins, like biochemical, paleontological, ecological, phytosociological, pedological, climatic, agronomic, plant uses, ethnobotany, etc... (again avoid re-invent the wheel)
All together this is a sound and state-of-the-art XML foundation; of course a lot of details are left.
Cheers
JMV