GETTY John Balcombe says that fish are smart, sensitive creatures that can learn and enjoy pleasure

John Balcombe’s new book shows how this fascinating branch of the Animal Kingdom is filled with smart, sensitive creatures that enjoy pleasure and have the power to learn. Among the incredible examples of their “sentience” – the ability to feel, perceive and experience things in life – is an ability to enjoy pleasure and also recognise human faces. Experiments show how fish will respond to sensations of being stroked and how it reduces stress hormones in their bodies as well showing how they can recognise human faces among a large group of people.

British-born Dr Balcombe, who is currently Director of Animal Sentience with the Humane Society Institute for Science and Policy in Washington DC, shows how much fish are like humans in his new work: Fish Have Feelings, Too: The Inner Lives of Our Underwater Cousins. Speaking today, Dr Balcombe explained how scientists have been able to identify how sentient fish are through observations in their aquatic domain and through experiments. “Science shows they have cognitive, emotional lives, they have social and sex lives, it’s just that so much of that science is tucked away in scholarly journals and the general public rarely gets to see any of it and that’s why I wrote the book,” says Dr Balcombe.

GETTY Experiments show how fish will respond to sensations of being stroked

Among the illustrations he uses to illustrate the incredible abilities of fish is they that groupers and moray eels can go hunting together using “referential signalling” and how they also like to give and feel pleasure. Cleaner fish get to eat parasites on larger fish by providing a massage service. “These are conscious animals and, to speak of emotions, I like to give the example of pleasure,” he explained on BBC Radio Four’s Today programme. “Fishes use touch to reward others of their own kind or other species, sometimes to curry favour.

GETTY Dr Balcombe has not eaten fish for 30 years

“Little cleaner fishes ply their trade in reefs, plucking parasites off client fishes. The cleaners will take breaks from that and they actually caress these client fish with their pectoral fins probably as a way of currying favour to essentially inform them ‘hey, you wanna come back to me, I give nice service and I even give you an extra massage for good measure…” Studies have shown how fish can be encouraged to be stroked so they produce the hormone, cortisol, to help them become de-stressed, he says. “We are talking about an animal who is emotional and can enjoy feelings of pleasure which helps them to recover from stressful experiences. Quite a lot like us. I think what’s particularly compelling it’s rather like the human condition. “They are very different from us but their brains are very capable of doing what they need to do.” Dr Balcombe also dispels myths that fish have poor memories, only being able to retain things in their tiny brains for a few seconds.

GETTY Experiments have shown that fish can recognise human faces

“It’s an old myth, it’s completely not true,” he says. “They have good memories. They monitor what others are doing when they are watching them – it’s called the audience effect.” Fish can also recognise humans, too. “In a particular study that has been done, I believe they presented them with 40 faces only one which they had seen before and fishes would pick out the one that was familiar,” explained Dr Balcombe. “They also removed clues like hair, which we find quite useful to identify faces, but they could still recognise faces even without hair.”

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