I thought that I would also mention that in addition to The Plants List, the eBird project also uses on overlapping concepts in its bird list (it does have concepts for common hybrids)

What is clear to me is that you cannot create graphs like these if every observation can have X number of species (especially those that overlapping ) without any indication which is is the most appropriate one.

eBird Occurrence Maps Northern Cardinal
http://ebird.org/content/ebird/about/occurrence-maps/northern-cardinal

NCBI is also similar.

Perhaps a member of the consensus committee can comment?

-- Pete
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Pete DeVries
Department of Entomology
University of Wisconsin - Madison
445 Russell Laboratories
1630 Linden Drive
Madison, WI 53706
Email: pdevries@wisc.edu
TaxonConcept  &  GeoSpecies Knowledge Bases
A Semantic Web, Linked Open Data  Project
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