noun, noun which may take the genitive case particle 'no'
evolutionist
Refers to a person who accepts or advocates the theory of evolution. Can also be used attributively with の.
彼は熱心な進化論者だ。
He is an ardent evolutionist.
進化論者の立場から議論する。
Argue from an evolutionist standpoint.
進化論 is the theory of evolution itself, while 進化論者 is a person who supports or studies it.
Compound of 進化論 (theory of evolution) + 者 (person).