Fish can cheat, and apologise afterwards

Think of intelligence in the animal world and you rarely think of fish. But there’s growing evidence to show that the various species living in the planet’s waters have greater intellects than we’ve given them credit for

Many people don’t think of fish as being intelligent. Fish brains are too small and they’re too distantly related to humans to be clever; they lack feelings; they can’t feel pain – at least that’s how they’ve been typecast. Their simpleminded reputation means that people still tend to treat fish differently from other animals, with far less concern for their welfare (just imagine if we slaughtered cows by drowning them in the sea).

In the past, many scientists overlooked fish intelligence and didn’t bother testing for it. Those that did often used experiments that weren’t relevant for these animals, with senses so different from our own. But the science of fish cognition is catching up, and new studies are showing that fish are much smarter than previously thought. Signs of higher intelligence among fish are not only forcing a rethink of their lives and the way we treat them, but also how brains and animal intelligence evolved.

These remora use modified dorsal fins to attach harmlessly to larger animals, enjoying the protection offered by the host

The pores all over the snout of this lemon shark are called ampullae of Lorenzini. They are present on all sharks and rays, and are a ‘sixth sense’, allowing the sharks to detect electrical signals coming from the movements of other animals – even if they’re underneath sand