There's lots going on beneath the surface that has major effects on fishes, other animals, and ecosystems. I recently read a fascinating and important research essay by Université Toulouse III Paul Sabatier's Dr.
Lisa Jacquin and her colleagues published in Frontiers in Ecology and Evolution called "Effects of Pollution on Fish Behavior, Personality, and Cognition: Some Research Perspectives." It's well known that fishes are highly diverse sentient and intelligent beings who also display various complex personalities and large individual differences in how they respond to stress, and this paper clearly shows that fishes are far more than mere edible streams of protein who don't mind being cooped up in a small barren aquarium.
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