Table 4. Term adoption example in the Fish Ontology.

Term example	Helfman et al. (2009)	VTO (Midford et al., 2013)	NCBITaxon (Federhen, 2011)	Fish Ontology (FO)
Furcacaudiformes (order)	Classified as Subclass of Thelodonti (superclass).	Classified as subclass of Agnatha (class).	Not classified.	Follows and reuses the VTO terms.
JawlessFish	Contains species and information for jawless fish species.	No classes and annotations found, but related species are classified.	No classes and annotations found, but related species are classified.	Follows Helfman et al. (2009) for labeling.
LobeFinnedFish	Classify as Sarcopterygii (page 4).	No classes and annotations found, but related species are classified.	Classified as Coelacanthiformes.	Follows Helfman et al. (2009) for classification and labeling.
Gobiidae (family)	Listed and classified as family.	Listed and classified as family.	Listed and classified as family.	Follows and reuses the VTO terms.
Oxudercinae (subfamily).	Not listed.	Not listed.	Classified as a subclass of Gobiidae (family).	Follows and reuses the VTO classification up to the lowest existing taxonomic terms covered (Family Gobiidae). Adopts NCBITaxon terms for Subfamily Oxudercinae onwards.