Before the 20th century, and into its early decades, the pace of discovery (and "discovery") of new species was fast; during this period, with numerous collecting expeditions into species-rich areas not previously visited by western ornithologists, up to several hundred new species per decade were being described.
The purpose of each of these was to collect together in a single paper, for ease of reference, all new species' descriptions published in the period of study, and to present an analysis of these, indicating which represent valid species, and which, for various reasons, do not.
Meise presented his review to the Eighth International Ornithological Congress (IOC) in Oxford.
Meise's papers were: After the Second World War, ornithologists based at museums in the American Museum of Natural History produced further reviews; again, each of these listed newly described species and presented an analysis, indicating which were and were not good species.
To date, six such papers have been compiled; they are, in chronological order: No further detailed analyses have been published since the 1992 paper, although the British magazine Birding World has published two articles by Oscar van Rootselaar listing newly described species since 1990: See Bird species new to science described in the 2000s.