Fish have feelings and intelligence on a par with other animals and deserve better consideration of their welfare, according to a behavioural biologist at Australia's Macquarie University.
Dr Culum Brown came to the conclusion after reviewing the scientific evidence on fish capabilities.
He found that fish have good memories, lived in social communities, co-operated, and learned from one another.
They displayed behaviours normally seen in primates and were even able to build complex structures and use tools.
While their brains differed from those of other vertebrates, they contained structures that performed similar functions seen in other animals.