names and numbers

Richard Pyle deepreef at BISHOPMUSEUM.ORG
Sun Oct 21 16:15:14 CDT 2001

> A circumscription that is the sum of all the determinations (by a single
> individual, of course) is bottom-up, and can only be extended by the
> original determiner--If I have a freshly collected California poppy at
> hand, there is no way to know if the late W. L. Jepson would have
> determined it as Eschscholzia californica.

I don't think it's necessarily safe to lump all determinations made by a
given expert into a single Circumscription, especially if these
determinations span many years.  If we think of a Reference as a
time-stamped Expert, then really a single Reference is the best we can do
for combining determinations under a single Circumscription. Thus, the
"Assertion" is the natural point of reference for Circumscriptions, because
it is the intersection of a Reference and a taxon name, and also serves as
the source for Determinations.

> A circumscription based on a description is top-down: the description can
> be applied to specimens that its author never saw. But those applications
> each have their own determiner.

Hmmm....I'll have to think about this some more, but my first reaction is to
treat all Circumscriptions as the same, mapped through references (via
assertions), and grounded in specimens only to the extent that those same
assertions serve as sources for determinations of specimens.

> The former circumscription would be easy to implement (AFAIK all specimen
> databases that record every determination of a specimen could do it), and
> more objective. But its lack of extensibility would be a problem, one that
> might be solved to some extent by a hierarchy of circumscription ("Jepson
> determined it, I believe it, that settles it, and I've made these
> additional determinations as well, so mine are a superset of his").

That's where you get into the question of mapping assertions against other
assertions (or circumscriptions against other circumscriptions).

> I don't see any clear way to implement the latter type of circumscription.
> It's easy enough to record descriptions, but applying them is problematic
> in any circumstance, database or otherwise.

Yes, I see what you mean -- but short of some highly complex system that
tracks populations, it seems to me that the most practical way to define
circumscriptions is via Assertions, and then on to Specimens via the
Determinations sourced to those same Assertions.

O.K., my head has now completely resoved to mush, so I have to go watch TV
or something.....


Richard L. Pyle
Ichthyology, Bishop Museum
1525 Bernice St., Honolulu, HI 96817
Ph: (808)848-4115, Fax: (808)847-8252
email: deepreef at
"The views expressed are the author's, and not necessarily those of Bishop

More information about the Taxacom mailing list