Procedure:
To perform this experiment, one would need to analyze the genes of the Northern fence lizards from sites affected with fire ants and sites that haven't been. You would also need to investigate whether the adult lizards from the non-affected sites could learn how to twitch if placed near sites with fire ants for a period of time. This would help determine if it was an evolved trait or if a genetic trait for twitching already existed before the fire ant invasion.