In evolutionary biology, one who believes in gradualism.(noun)
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Use "gradualist" in a sentence
"#4: Darwin was certainly a gradualist, that is to say a proponent of natural selection"
"In fact, the view of world markets on the prospect of major, disruptive reform in Japan has shifted 180 degrees since Prime Minister Junichiro Koizumi sacked his "gradualist" FSA chief on Sept. 30 in favor of Takenaka."
"Quizzed by fellow judges on the Judicial Services Commission and the Minister and Deputy Minister of Justice, Langa dismissed reports that he was a transformation "gradualist"."