Normal dog behaviour?

Well recently my younger female dog has started to hump :o my older female dog, I know its a sign of dominace or so I'm told but is there a way I can stop it? I've tried telling her off so she stops but she carrys on after about half an hour

Maybe the younger dog is just bored & acting out by causing a fuss.
Do you keep her busy most of the day with walks, games,etc?

I forgot I posted :o

She's not really a playful dog to be honest, she gets a walk everyday off lead with my lab over a park so shes exercised over there and shes not really allowed to play with toys indoor because they fight over them but saying that she only want to play with the toys to steal them from the other dog once shes got them she loses interest

My female dog Ginger goes through phases where she would do this - only on peoples legs. She is spayed (I assume yours are also), but I thought maybe these were periods where she might have otherwise "been in heat"? I don't know. But she stopped on her own... and hasn't done it in quite a while. actually, i would be interested in knowing if there is some scientific/instinctual reason for this behavior. I do know that it helped to verbally discourage and to physically separate. :confused:

They have both been spayed and its been that way since they were puppies so its been about 3 years at least, I do tell her off and pull her away but I dont shout at her or anything because I dont really know why shes doing it there could be a perfectly good explanation and then il feel guilty :o

I remember reading somewhere that its a dominace thing but I wasnt sure if I was right about the situation because its two girls, I wasnt sure if it was just boys doing that? :confused:

On a lighter note she seems to be calming down alot now with it, I havent caught her doing it much in the last few days :)