Most people think of fish as somehow lesser than pigs, cows, chickens and other land animals.
We have a vague notion that fish aren't as intelligent (think of the common belief that fish only have a three-second memory) and genuinely wonder whether they can feel pain. Lots of people consider themselves vegetarians, but eat fish while abstaining from all other meats.
Australian biologist Culum Brown has a provocative argument in response, based on his years of research into fish behavior and learning. "They're just not any less intelligent or sophisticated than terrestrial animals," he says. "That idea is a total myth."