[tdwg-tag] [tdwg-rdf: 105] Re: Any TCS users with experiences to report?

Richard Pyle deepreef at bishopmuseum.org
Wed Nov 28 22:21:46 CET 2012

> So the question in my mind (and I think a question posed explicitly
earlier in this thread) 
> is whether enough of the technical stuff you want to do with TNUs can be
done with 
> the TDWG Taxon Concept ontology which is based on a ratified TDWG standard

Yes, I agree that this is the key question right now (speaking as TDWG
Convener for the TDWG-TNC Group); unfortunately it's not one I have time to
address in detail this week.  But I think it's the conversation we ought to
be having. 

> The 2009 "thing" is something that L. Urbatsh had in his head - 
> the idea of how he thought the name "Juncus diffusissimus Buckl." 
> should be applied to real organisms and the specimens that come 
> from them.  We don't know what that idea is but presumably he had 
> one and we could assign a persistent identifier to it and describe it 
> using the string "Juncus diffusissimus Buckl. sec L. Urbatsch 2009".   

Ah!  In that case, it only becomes a TNU when it is documented (i.e., when
it is "used").  The data model is very liberal in terms of what constitutes
"documentation" (="Reference", in the GNUB data model), but chemical signals
inside a person's brain would be out of scope for "documentation".  However,
once he's written it down on a determination label, then it becomes a TNU.
The trick then becomes how to map what was in his head, to what is defined
in some way.  When people write determination labels on specimens, they
usually don't include lots of details about the scope of the taxon concept
they had in mind when assigning that name to that taxon.  This is why an
assertion is needed (as per Nico's emails on this thread):  Someone (either
Urbatsh himself, or the collection manager, or someone else) needs to make
an assertion that the TNU recorded on the specimen determination label maps
to some other TNU with a well-documented concept definition (e.g., a
published revision), through some set-theory relationship.

> I was thinking that was what you meant by TNU.  Whether or not 
> it is better to proliferate a bunch of additional TNU instances, assign 
> them their own identifiers, and relate them to each other is a technical 
> detail that as an end user I'm happy to let you take care of within your 
> GNUB system.  End users want a persistent identifier of some sort to 
> link identification instances to.  They will hopefully find it through a 
> user-friendly interface that hides the ugly details you are describing

I have to admit that I'm a little squeamish about minting TNUs for
determination labels, and I wouldn't encourage it.  However, for the
collection managers out there, sometimes this is the only way you'll ever
translate scientific names on specimen labels into well-defined taxon
concepts. The only part that gets fuzzy is the notion of dwc:Identification.
The way we model it for our specimen data is that each Identification
instance gets its own GUID, and basically says "this person on this date
determined this specimen to fall within the implied concept of this TNU".
In other words, an Identification bridges a specimen instance to a TNU
instance according to some person (with other metadata, like date, etc.)  In
the ideal world, whenever anyone every made a specimen determination, they
would add a "sensu XXXX" to the name they applied.  The unfortunately
reality is that the vast vast vast majority of actual specimen data do not
meet this ideal. Thus, we're left to guess what concept they had in mind
when making the determination.  In some cases, we can confidently infer that
the person had a particular concept in mind (the example I gave on the
expert visiting a collection, making specimen determinations, and later
publishing a revision).  You can also confidently build these links whenever
a publication includes the "Material Examined" section.  But in most cases,
there really is no other choice than minting a TNU for the determination
label, then hoping that TNU will eventually get cross-linked to other TNUs
with more well-defined concept definitions.

> Let's say that I assign a persistent identifier [URI1] to the TNU we are 
> talking about here, "Juncus diffusissimus Buckl. sec L. Urbatsch 2009" 
> and that I'm right that by TNU we mean the idea that Lowell Urbatch 
> had in his head about how he meant to 

OK, I'll assume there is a determination label in a jar with that species
name on it, and credit to L. Urbatsch, and dated to 2009.  This
determination label serves as the basis for the TNU.

> We can assign a tc:accordingTo property to [URI1] with the object 
> of that property being some kind of resource whose metadata 
> says that Lowell Urbatcsh used the name in some sense known 
> to him in 2009.  

I'm not sure this is right, because it sounds like you're saying that
tc:accordingTo should point to a TNU.   However, tc:accordingTo should point
to a "Reference" (sensu GNUB data model).  As such, there would be a
Reference instance in GNUB with a GUID that refers to the determination
label.  The "author" of that determination label would be Lowell Urbatcsh,
and the date would be 2009.  This serves the same function as a journal
article, or book, or any other more familiar form of documentation
("Reference"); but instead of being ink on paper in thousands of copies
distributed in libraries around the world, it's ink on paper on a label
attached to a specimen.  So, tc:accordingTo would point to the GUID for the
*Reference* instance; not a TNU instance.

> (We could work out the details of how one would write that metadata 
> but there probably is enough stuff in the Dublin Core and FOAF 
> vocabularies to do it.  I think later in your email you said GNUB calls it
a "Reference".)  

Right -- exactly.  A Reference is a piece of documentation -- a journal
article, a book, a field notebook, a piece of correspondence, a
determination label, etc.  A Reference may be associated with zero, one, or
many TNUs.  In the case of determination labels, this is often a case where
one reference is associated with only one TNU.  But that doesn't mean
they're the same thing.  A Reference is a Reference, and a TNU is a TNU, and
tc:accordingTo should point to a Reference, not a TNU.

> Now let's say that in 2012 I call him on the phone and say "hey Lowell,
> taxonomic treatment were you thinking about in 2009 when you annotated 
> that specimen in the NLU herbarium with barcode LSU00000428?" and 
> he says "Gleason and Cronquist, 1991".  I have two choices:
> 1.  add  a tc:describedBy property to the metadata for [URI1] with the
> urn:isbn:0893273651 (a persistent URI representing Gleason and Cronquist
> and "promote" the resource identified by [URI1] from generic TNU to
"deeper" taxonomic concept.
> 2. create a different [URI2] which has a property/value pair of
> urn:isbn:0893273651 , then somehow relate the royal URI2 taxonomic concept

> to the lowly URI1 generic TNU.  

I need to get my head around tc:describedBy before I can respond in detail;
but in GNUB space, there would be a mapping of the TNU for "Juncus
diffusissimus Buckl. sec L. Urbatsch 2009" (the determination label), and
the TNU for "Juncus diffusissimus Buckl. Gleason and Cronquist, 1991" (the
publication -- assuming that G&C 1991 used the same
name/combination/spelling).  In this case, the mapping would be of type

I can't comment on the OWL implications. My role here is to make sure that
our "things" are consistent. (a Reference being on "thing", a TNU being
another "thing", and also how the "Identification" thing and possibly the
taxon concept "thing" relate to these other things).

Form what you describe later in your email, I guess I'm in favor of option

> 3. If the tc:Taxon instance has a tc:accordingTo property, it is elevated
> TNU status because we can know who used the name and when if we 
> investigate of the object of the tc:accordingTo property further.  

Again, tc:accordingTo should not refer to a TNU.  It should refer to a

> If it made Rich feel better, he could mint a class URI for the deep 
> taxonomic concepts which could be used in rdf:type statements in 
> addition to the basic rdf:type of tc:Taxon .  

It actually wouldn't make me happier to do this.  My preference is to use
the TNU GUID as the proxy for the concept, rather than mint new GUIDs for
concepts.  This is how we do it on the nomenclatural act side.  We don't
create a new GUID for the nomencatural act -- the GUID for the TNU carrying
the nomenclatural act is a sufficiently unambiguous proxy.  (However, the
new draft GNUB model does parse out each nomencaltural act into one-to-many
nomenclatural "events" -- but that's a separate conversation).

> I see this as a way to make rapid progress on this front by leveraging 
> work which has already been completed and accepted by TDWG but 
> not really implemented.  The TDWG Taxon Concept ontology and TCS 
> may not do everything that people want as far as allowing one to define 
> all of the set relationships required to do the fancy stuff.  But I don't 
> see why that can't be added in a TCS 2.0 that is backwardly compatible
with TCS 1.2 .  

I wholeheartedly endorse this approach!  In December I'll take a closer look
at the Taxon Concept ontology and I'll discuss with Rob Whitton (CC'd --
sorry, Rob!) how we might actually start implementing services that output
GNUB content in conformance with tc.  Rapid progress is definitely a Good


Richard L. Pyle, PhD
Database Coordinator for Natural Sciences
Associate Zoologist in Ichthyology
Dive Safety Officer
Department of Natural Sciences, Bishop Museum
1525 Bernice St., Honolulu, HI 96817
Ph: (808)848-4115, Fax: (808)847-8252
email: deepreef at bishopmuseum.org

Note: This disclaimer formally apologizes for the disclaimer below, over
which I have no control.

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