It's a dominance thing. We got our dog at 14 weeks. He was a rescue and had been neutered several weeks before. Around age 6 months he started humping just about anything - living or not. It went away a few months later. It's adolescence.

Maybe she's trying to keep up with Amanda McCracken. You know -- doing everything but getting a boy in her cooter.

My almost 10 month old girl dog started humping in the last month or so.

Based on what I read, she does it to show dominance. She only does it to dogs who she is dominant over and only if there are other dogs there. It's funny, she is showing the other dogs that she isn't at the bottom of the back. So far she has never done it to any dog that minded.

Now she doesn't like other dogs humping her and will do what she can to stop them (boys or girls).

I think you need to put a stop to it when she is doing it to humans. Because she is not allowed to be dominant toward you.

But have you seen your arms, Amy? It's your own fault, really...

Katrina is right though... it's a dominance thing. It needs to be nipped like any other bad doggy behavior. Just tell her "No" like you do when she barks. Eventually she'll learn that it's not okay to hump. At least, that worked for my very stubborn jack russel when he was fixed.

I'm sure she was just playing dominatrix, and would have stopped short of finishing the job. ;)