re: Actually, Goldfish DO have long-term memory.
Heck, I've trained rats and dogs. Even flatworms (that have a good deal less neural capacity than goldfish) obviously will come to expect an electric shock when turning left or a food reward when turning right.
I'm told they've found that single-cell life can be trained in this fashion too. Learning what works best then remembering that lesson and acting on it is not something that humans own exclusively.