How do I be myself in a group of men who compete with and talk over and correct me whenever I show my intellect?

A friend of mine wanted to know why his dog doesn't rush him at the door; instead, she submits. It went:

Me: "If your dog rolls onto her back when she sees you, she's acknowledging your dominance. She's not scared."

Dude: "Not sure if that's true."

Me: "Yeah, I'm sure it's true, brah."

beta males scan group for deference

If I try to hold my own, I'm a know-it-all bitch.