The term Darwinian refers to the theories of Charles Darwin, a British naturalist who proposed the theory of evolution by natural selection. The crossword solutions for the term Darwinian are APES (4 letters) and APE (3 letters). An APE is a primate of the superfamily Hominoidea, which includes humans, gorillas, chimpanzees, orangutans, and gibbons. APES are distinguished from other primates by their larger size, more complex brains, and lack of a tail.