How have normal ears evolved to a rabbit's ears?

Hi there :) My question is how have normal ears (like a humans ears) evolved to a rabbit's ears? (assuming they did) And what does heredity have to do with it? Like, how could the parents pass down long ear genes if they don't have any themselves? :S Would it be because they need the long ears? But then how does the environment relate the the genes? Thank you so much if you have ideas! :)!!