With fish farming on the rise, a scientific issue takes on urgency
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Do fish feel pain?

It sounds like a simple question, one that ought to have a simple, yes-or-no answer — the kind we humans tend to crave. But if there's a query that manages to combine uncertain science, definitional problems and occasionally blind emotion, it's this one.

For a start, even language can get us into trouble. At least in popular Western culture, we have a long history of attributing human motives and emotions to all manner of animals and insects.
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"Animals often do things that resemble things that we do," he says. "But it's a very different matter to interpret that (as meaning) they're thinking and planning what they're doing."

That's especially problematic with animals, like fish, that followed a different evolutionary path than humans, endowing them with brains and neurological systems far different from our own. For Rose, fish just don't have the necessary mental equipment to think about and feel pain in the way we do.

"If you look at fish in general, their brain stems are highly developed, but the cerebral hemispheres are not highly developed," he says. "They have the rudiments of what we have, but it just isn't very expanded, and everything I know about things like awareness indicate you've got to have more brainpower upstairs than they have."

In recent years, however, there has been a lot of debate on the pain issue, including a symposium last week at the University of Guelph that featured Victoria Braithwaite, one of the co-authors of a recent (and controversial) British study.
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So why, then, this renewed interest in whether fish experience pain? It all has to do with fish farming, which has lately come under attack by some animal-rights groups, especially in Europe.

And if you want fish farming to be governed by the same sort of rules that have long applied to the treatment of traditional farm animals, then it's more than a little helpful to have fish considered as being not much different than cattle or sheep.

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