1922 1929 1936 1943 1950 1957 1964 1971 1978 1985 1992 1999 2006 2013 Number of splits and lumps in the AOU's Checklist of North and Middle American birds between 1889 and 2014 0 10 20 30 40 Splits Lumps
2000 Species redescription effort beyond species description effort Year Accumulated species definitions Species descriptions as of 2014 Species definitions modified (1889 to 2014)
2000 2100 2200 2300 Species redescription effort beyond species description effort Year Accumulated species definitions Species descriptions as of 2014 Species definitions modified (1889 to 2014)
2000 2100 2200 2300 Species redescription effort beyond species description effort Year Accumulated species definitions Species descriptions as of 2014 Species definitions modified (1889 to 2014) Species definitions (ignoring Central American species)
2000 2100 2200 2300 Species redescription effort beyond species description effort Year Accumulated species definitions Species descriptions as of 2014 Species definitions modified (1889 to 2014) Best fit line (spdef = −53210 + 55.54(year) − 0.01363(year^2)