Complex sentence: This sixth diet type is usually in association with one of the above, as very few birds are solely folivorous, a few species of Galliformes come to mind, however they are not considered to be Softbills.
Split into simpler sentences: This sixth diet type is usually in association with one of the above, as very few birds are solely folivorous. Several species of Galliformes are frolivores, however they are not considered to be Softbills.