Fish have surprisingly remarkably intelligence including complex social learning, communication, memory, personalities, pain, tool use, negotiating, consoling and punishing, play, dealing with distractions and math ability. 1
Fish Cooperation and Communication
Surprisingly, three completely different species signal each other and cooperate to hunt. A grouper fish signals an eel with a head motion and a pointing headstand and the eel cooperates with the grouper to route prey that are in crevices too small for the grouper. The wrasse understands the sign language, also, and sucks out the prey or breaks the corral with powerful jaws from crevices. They all share their bounty. Cooperation among animals was observed before with monkeys. This type of behavior is contrary to simplistic interpretations of natural selection.
Clownfish have a vocal language that establishes and defends their social position for breeding. Some of the sounds are aggressive signals along with fighting with another fish, and other sounds signified the fish that is dominated. The sounds of the dominant larger fish are different being longer and in a lower frequency. The largest in the group is female, and the second is male. All others in the group are neither gender. If something happens to the female, the ranking shifts and a new female and male are chosen by rank.
Cleaner fish advertise with bright yellow and blue colors to become the associate and colleague of particular large predators that are either temporarily travelling through or more permanently near that particular reef. They create “cleaning stations” where the larger fish know they will be cleaned off. In this arrangement, the cleaner fish gets a great meal of parasites and the larger fish has the equivalent of a spa visit.
In experiments, the grouper fish learned rapidly to signal to an eel with special movements of the head. They only signaled those particular eels that were cooperative.
Killer whales use accurate communication to line up together, flap in unison creating waves to knock a seal off of ice and the precisely cut it up.
Humpback whales compose new mating songs and these popular tunes then gradually spread east from Australia to French Polynesia.
Dolphins show advanced intelligence including self-awareness of markings on their bodies, previously assumed to be present only in chimpanzees and humans. Dolphins use tools such as covering their noses with sponges. They communicate and cooperate for fishing with each other and with fishermen.
Octopus finds its way through a maze, solves advanced problems, spreads cultural information, and mimics others. They use their arms to carry shells, and then, in order to conceal themselves, they flip them over and hide underneath.