This list's taxonomic treatment (designation and sequence of orders, families and species) and nomenclature (English and scientific names) are those of "The Clements Checklist of Birds of the World", 2019 edition, except that South African spelling is used. Taxonomic changes are on-going. As more research is gathered from studies of distribution, behaviour and DNA, the order and number of families and species may change. Furthermore, different approaches to ornithological nomenclature have led to concurrent systems of classification (see Sibley-Ahlquist taxonomy and ).