So we brought home a horse to "test ride" this week for my husand. Our newest furry friend, Ace, is a 4 year old gelding. He and my mare Masi are in separate pastures and share one fence. Sunday they were at the fence visiting each other and he would smell the ground, then stretch his neck and nose up and curl back his upper lip and show her his teeth. He wasn't trying to bite her. He did this multiple times. We checked and he didn't have anything stuck in his mouth. I've heard a couple different theories. Is this him flirting or being submissive?