Emotion is not just human. animals exhibit lots of different emotions. An easy example is fear. Anyone want to argue that all animals clearly exhibit fear in the face of danger? Organisms with a nervous system feel things and thats when it becomes a matter of complexity. Earthworms have a basic nervous system. many fishermen say worms dont feel pain so who cares about putting them on hooks. that basic nervous system tells them that the hook is quite painful. They are not that complex and I do not think their brains have the capacity for emotion. Fish on the otherhand are not basic organisms. They are much more complex and their brains do register more signals, such as emotions. Why do schooling fish need to be in a school? People can argue that it is just how they evolved or that is their instinct. Humans are also social creatures and without other human contact there is some degree of emotional response. Personality also plays a key role in this(antisocial behavior) but in development we need specific stimuli. I have two oscars with very different personalities and they are always together. If seperated, the albino becomes depressed and literally gives up on life. He lays flat on his side and will NOT move at all for days until reunited. The tiger oscar is more independent and continues feeding and swimming, but he becomes sluggish and his demeanor obviously changes. I am not basing my emotional fish theories on my oscars. Ive dealt with a variety of species with my fisheries experience. now some fish are pretty simple and I would not go as far as to say ALL fish are this complex. but there are many species complex enough to exhibit real emotion and IMO if you think emotion is strictly a human concept, you havnt spent enough time in the animal world
