Name Usage as Pricipal Data Vehicle for Name/Taxon Data Exchange
Nozomi Ytow1, Akira Sato2, David R. Morse3, David McL Roberts4
1 Gene Reserch Center, University of Tsukuba, Tsukuba, Ibaraki, 305-8572 Japan. 2 Academic Computing and Communication Center, University of Tsukuba,
Tsukuba, Ibaraki, 305-8571 Japan. 3 Faculty of Mathematics and Computing, The Open University, Walton Hall, Milton Keynes MK7 6AA, United Kingdom. 4 Department of Zoology, The Natural History Museum, Cromwell Road, London SW7 5BD, United KingdomTaxon concepts are always context dependant and must change to accommodate new knowledge. They are consequently inherently unstable. Taxomic data models either use taxon concept or name-usage as their principal vehicle. Although both are developments of the potential taxon (Berensohn, 1995), they differ in their definition of the terms 'taxon concept' and 'name'.
'Name' is sometimes mistakenly considered to be no more than a literal, i.e. a string of letters, rather like a luggage label. But consider: if the label were detached from its concept, what would it represent? We should properly regard the name as the relationship between the intension (membership list) and extension (character states) sets.
In using a name (a name-usage), an author must always employ a taxon concept and it could not be otherwise. The benefit of using name-usage as the principal data vehicles that it records simply the fact that a name was used and does not necessitate taxonomic scrutiny, although the data structure can be designed to maintain a flag indicating such scrutiny if it is required. Name-usage based schema consequently have wider coverage of data sources than schema based on taxon concept, make fewer demands on the data-creator and require less maintenance.