What is the most emotional species , what are the most emotional species, (insert more questions here..)?

I don't know how you would "measure" it. And please , forgive the term measure. I understand that not everything is based on a measurement as some times things are processed differently when a property of a unique "entity" possesses that property. Such as a dog, versus a cat. Or , if you're really abstract a plant versus a human. Or more sensible to most people, a human versus a dog.