Darwin core

[Stan Blum]

Dear Fred,

The home page at http://darwincore.calacademy.org provides links to three
versions of the DarwinCore that now being used as data transfer structures.
 That web site is being used to discuss the next version.  In all cases, an
XML schema specifies the concept definitions and data types.

The XML schemas COULD be interpreted as database structures, but I would
really like to emphasize that the DarwinCore is NOT intended to be a data
structure for a collection database.  The purpose and rationale behind the
DarwinCore are given here,
http://darwincore.calacademy.org/Documentation/PurposeGoals
but again, the purpose is much narrower than managing collection data.

You can look at the concepts contained in the DarwinCore (and the Curatorial
Extension -- http://darwincore.calacademy.org/PendingIssues/Extensions/) and
from these documents determine what things you might want to add, just
remember that the data types used in DarwinCore are designed to be a
meaningful intersection of many disciplines and a full representation of
none.  Further, they're optimized for query-ability and/or the ability to
combine data "smoothly".  For example, many people record latitude longitude
as degrees, minutes, seconds in their collection database because: a) it
came that way traditionally, b) they're used to it, c) they feel errors are
less likely, and/or d) they feel that precision is stored more faithfully in
that format.  DarwinCore, however, uses decimal degress because that format
is easier to query and is used in GIS.  Also, you will almolst certainly
find that additional information is important to you and and it is NOT
contained in the DarwinCore.

You should take a look at the page on collection database models that Walter
Berendsohn compiled to see a much broader set of examples.
http://www.bgbm.org/TDWG/acc/Referenc.htm

You might also want to take a look at the resources listed on the GBIF -
DIGIT site  http://www.gbif.org/prog/digit/links

Stan Blum
Research Information Manager
California Academy of Sciences