def self.disjoint_object_classes
    self.parent.disjoint_object_classes +
        self.collect_descendants_and_itself_to_s(TaxonNameClassification::Iczn::Available::Valid) +
        self.collect_to_s(TaxonNameClassification::Iczn::Available::OfficialListOfFamilyGroupNamesInZoology,
                          TaxonNameClassification::Iczn::Available::OfficialListOfGenericNamesInZoology,