Most importantly, I agree that the truth of these matters should be determined by interpretation of scientific evidence - experiments, fossil studies and the like.
I literally left school and went straight into music via art college for a year, and I've been so involved in my job of writing songs that the more actively involved part became channeled into standing on the stage and saying things that way.
I tend to get comfortable with the dialogue and find out who the person is in the script and try to hit that. People are sort of independent of their occupations and their pastimes. You don't play a politician or a fireman or a cowboy - you just play a person.