Studies show that fish have gradually, over the past several decades, shifted their ranges toward the earth's poles.
We are, or should be, fairly accustomed by now to stories like this. It's known that birds, and even plant life zones, are gradually moving north too. Polar bears are threatened. Ice is disappearing from polar zones and from the tops of mountains. And on, and on.
Still, deniers of this clear trend still exist, and by and large, governments are doing little to avert what could be a global disaster.
When I was young, my parents and many others, I believe, used to refer to fish as "brain food," in an effort to get us to eat that mostly tasteless white stuff that most kids didn't much care for. They may have been right. The evidence suggests that fish may have better brains than we do.