How does Melinda and Howard's interaction in the first scene of inherit the wind foreshadow the play's main theme?

Howard calls Melinda's father a monkey, and Melinda runs away. That pretty well sets the major theme for the play.

How does it foreshadow the plays main theme Intellectualism vs. fundamentalism?

The fact that Howard was learning about evolution and even considered that humans were descended from a monkey-like form was enough to spark this whole storm over science and religion in the town.