Due to the way classes are being indexed/searched, there are many classes that show up in the Bioportal search, that do not show up in AberOWL. I think that:
Intermediate words are not searched, e.g. try typing 'creatine,' which should ideally come up with the 'urine creatine [...] set of terms
Synonyms are not searched, e.g. try searching 'thigh girth,' which should come up as a synonym of 'proximal hind limb circumference'
The first issue particularly can make it seem like lots of classes are missing from the ontology
Steps to repeat:
Compare http://aber-owl.net/ontology/CMO/#/ with https://bioportal.bioontology.org/ontologies/CMO/?p=summary
Due to the way classes are being indexed/searched, there are many classes that show up in the Bioportal search, that do not show up in AberOWL. I think that:
The first issue particularly can make it seem like lots of classes are missing from the ontology