Matthew is showing Dave to a tour group
Matthew: This is Dave-apithicus erectus, one of the very few in captivity. His diet consists of black coffee and sarcasm.
Bill: How come no one thinks I'm funny?
Lisa: How come no one thinks I'm female?
Bill: We're misunderstood, I suppose. That's why guys like you and me gotta hang together.
Lisa: I'm not a guy, Bill. I'm a woman.
Bill: Prove it.
Lisa: (sarcastic) Ha ha ha.
Bill: See? I made you laugh.
Lisa: I'm a woman, right?
Dave: Well, the last time I checked. Though that was three months ago.
Vicki Lewis was listed in the credits for this episode, although she didn't appear.