Miss_Piggy, good luck on your audition!
That is odd that you need an acting audition for a non-performance field of study.
I’ve done many auditions, and been a director who has held many auditions, so hopefully I can give some good tips.
Be Real. Don’t be overly dramatic any which way in your performance. Be genuine about it. That is an acting tip for anything, really. But don’t make it look like you are trying to be genuine, just do it. This comes from being relaxed.
Be friendly. Smile at your adjudicators, and answer any questions, again, with sincerity. Don’t over-do the friendliness. Don’t be afraid to ask them how they are. But don’t pry.
Don’t go over your time limit (if given one). Directors have often seen what they want to see within the first 30-45 seconds of a monologue.
Be creative in your performance. Don’t just stand there and give the speach from memory. Act it, be it. Work some kind of blocking or body movement into it. But don’t pace. Again, be genuine.
If the director/adjudicator asks for you to go through the speach differently, offering directorial ideas, make sure that you follow those suggestions as best as possible. Directors will often do that to see how directable you are, to see how well you take instruction, and to see a marked difference between your original performance and your new one.
I think since you are going for a lit/crit/history field of study, make sure that you know the character you are performing inside and out and can justify the choices that you made in your portrayal of that character.
If at all possible, find someone you can test your audition on and get constructive feedback from.
Again, best of luck. Smash their faces in! (Not literally.) Let us know how it goes!!!