The GBIF terms biorelation vocabulary is a vocabulary to express relations between biological objects, parts and structures, habitats, molecules, etc. In its first iteration, it is closely modeled after a subset of the OBO Relation ontology (RO, https://github.com/oborel/obo-relations previously at http://code.google.com/p/obo-relations/) which replace the earlier OBO_REL ontology (http://www.obofoundry.org/ontology/ro.html). The reasons for providing a separate ontology are to provide the ability to extent with additional terms and make the dependency on the owl productions of RO optional.
Notes: The RO URIs do not resolve to proper definitions. For comparing biorel definition with original definitions, http://www.ontobee.org/browser/index.php?o=RO is useful, using the label rather than then URI. At the time of this writing, several terms could not be compared, the definitions were not shown and the status indicated as “pending final vetting”.Namespace URI: http://rs.tdwg.org/biorel/ with preferred namespace prefix “biorel”.