[tdwg-content] tdwg-content Digest, Vol 20, Issue 17

[Richard Pyle]

My turn to respond after traffic-jam reflections.... 

> What we need to realize is that in doing this, we are 
> establishing establishing dwc:Individual as the de facto 
> "aggregation" unit of the sort we have talked about 
> previously.  I suppose that is OK as long as we provide 
> sufficient means for humans or semantic reasoners to be able 
> to know what they are getting information about when they 
> retrieve metadata about an Individual.  That can be done for 
> humans by making appropriate comments in the proposed 
> dwc:individualRemarks .  For machines, I have been 
> re-thinking the idea of having dwc:individualCount being a 
> property of an Individual.  In an earlier post, I suggested 
> that it should remain a property of Occurrences, since the 
> number of Individuals can change over time (think wolf pack 
> or plant deme over time).  

In my mind, if the "Individual" is something like a wolf pack, and the wolf
pack changes composition over time, then you're really dealing with
different instances of a "wolf pack" (not just different occurrences of the
same individual).  There may be a desire to relate the two Wolf Packs
together in some semantic way, of course.

> However, in the current context, 
> something like dwc:individualCount (if not individualCount 
> itself) that is a property of Individual could have 
> controlled values of "1" and ">1".  

Hmmm....I'd rather keep individualCount as a numeric value (rather than a
controleld vocabulary), to allow specific values to be provided for numbers
of specimens in a lot, numbers of individuals seen in an observation, etc.

If you want a controlled vocabulary for semantic purposes, I'd favor
something like a new term "individualScope" being used for such purposes.
Values in a controlled vocabulary might include things like "Single",
"Group", "Aggregate" "Absent", etc., each with carefully worded definitions.

> The other issue would be how to indicate that one of these "aggregate"
> (individualCount>1) Individuals was segregated into several 
> Individuals at a lower taxonomic level (e.g. partially sorted 
> lots of marine organisms get more sorted, fossil aggregations 
> get separated into individual fossils, an image of a forest 
> has individual trees delineated).  Rich has stated that this 
> would be necessary any time subsets of the original 
> Individual were given divergent Identifications and I agree 
> totally.  Assigning new GUIDs to these new Individuals would 
> be no problem and I suppose Pete's suggestion of using 
> "hasPart" and "isPartOf" could be used to establish the 
> relationships between the original Individual and its "children".

Yup, I think we're on the same page on this one.

> If the 
> proposed addition goes through, we need to have a really good 
> Google Code entry that summarizes the understanding that we 
> have come to in this discussion (if we have come to one! :-).

Agreed.  We also need to be clear on what terms that currently fall within
the Occurrence class should properly move to a new Individual Class.  My
vote would be for:

individualID (unless moved to Record-level terms)
individualCount
preparations
disposition
previousIdentifications
associatedSequences

This also assumes that dwc:catalogNumber and dwc:otherCatalogNumbers be
re-assigned to Record-level terms. Was there some reason this isn't
appropriate?

Some of these are certainly debatable.  For example, the
PreservedSpecimen-centric "preparations" and "disposition" really do seem to
me to be properties of the Individual, not of the Occurrence at which the
Individual was extracted from nature. But I can see a problem when the same
Individual is first seen in nature, then is extracted later as a specimen;
in which case it seems weired to include these properties at the level of
Individual.

I think if we were going to be really pure about this, we should generate
two instances of Individual for each PreservedSpecimen: one representing
effectively an observation at the moment of capture (which would technically
have as basisOfRecord "LivingSpecimen" or "HumanObservation", and is linked
to the Occurrence), and the other representing the preserved specimen after
it is curated and processed (linked appropriately to the first Individual
instance).

But I think that's going too far.

OK, enough for a while....

Aloha,
Rich