evolutionist

noun

1. A proponent or supporter of evolutionism.

   “Ironically, the argument used today by Roadruck and other designists—that their teachings should receive equal time in schools—mirrors the one employed by evolutionists some 75 years ago.”

2. (broadly)Someone who believes in the capacity of people to change.

   “Aeschylus is in fact an evolutionist as regards both gods and man.”