It turns out fish can not only remember things; they can plan, use tools, socialize and play.
They are far more intelligent than previously thought and, more importantly, they are sentient. That is, they can experience feelings such as fear, frustration, comfort and enjoyment.
Perhaps most important of all, they can feel pain.
Yet, for centuries we have regarded fish as unintelligent, unfeeling creatures of little status and low value, except as food.
So what has changed?
In a word, science. Over the last two decades, research has led to a scientific consensus confirming that fish can feel pain and experience emotions. Study after study has shown that fish are not who we thought they were.