Any time a creature reacts to a particular stemuli, it does so because it is experiencing some sort of emotion. It might not be something we would experience, or it might be something we do experience. I know that they experience fear. And they seem to experience other emotions as well.
Emotions are experienced even without our knowing it sometimes, and we even know sometimes but have no idea why we are experiencing it. We can name our emotions for the most part, but I think we would be assuming too much to think humans were the only creatures capable of emotions.
Try to explain the emotion we call love. In reality, love for our children is simply a maturnal instinct we have. And there are humans that are simply not capable of that emotion. Love for our spouses or significant other can easily be explained as physical attraction. Emotion? Or simply a physical attraction? I can show you some females that you would have difficulty loving, since there would be zero physical attraction. Same goes for men. We are attracted to what pleases the eye, so is that actually love? No matter what emotion you might be experiencing, a sudden change in your hormones can change that emotion just as suddenly. Every brain reacts to homonal change. And the way that brain interacts with the body can be considered an emotion if you think about it.
