Nerves, brain structure, brain chemistry and behaviour – all evidence indicates that, to varying degrees, fish can feel pain, fear and psychological stress.
It turns out emotional attachment to a partner is not unique to humans or even to mammals. Breakups really suck, even if you're a fish. The scientists started by giving females a chance to express a preference between two males.
Surprisingly, science has found that fish are capable of recognizing their owner's face, even if the owner is standing by the tank with other people. Fish can develop an association between something they like, being fed, with the person who feeds them.
“Fish do feel pain. It's likely different from what humans feel, but it is still a kind of pain.” At the anatomical level, fish have neurons known as nociceptors, which detect potential harm, such as high temperatures, intense pressure, and caustic chemicals.
It's widely debated, but technically, yes. But it depends on how you define “love.” Fish are able to recognize their owners and seek pleasurable experiences. As they remember your face and correlate it with pleasurable experiences like eating or being pet, they may learn to show affection in some ways.
The cerebral cortex and limbic system are absent in fish. Cerebral cortex, which is what permits other animals to cry.
Can your pet fish recognize your face? A new study says, Yes, it probably can. Researchers studying archerfish found the fish can tell a familiar human face from dozens of new faces with surprising accuracy.
“Fish are more intelligent than they appear. In many areas, such as memory, their cognitive powers match or exceed those of 'higher' vertebrates including non-human primates.” Fish's long-term memories help them keep track of complex social relationships.
As well as getting water through osmosis, saltwater fish need to purposefully drink water in order to get enough into their systems. Where their freshwater counterparts direct all of the water that comes into their mouths out through their gills, saltwater fish direct some into their digestive tract.
Despite differences in brain size and form, fish have been scientifically proven to have memories lasting months, perhaps even years, as well as the ability to recognise and consciously avoid pain and danger, seek out reward, navigate mazes, and even use tools.
Yes, fish can hear you talk!
Sounds that are created above water typically do not carry enough force to penetrate the surface tension of the water, so talking on the boat or loud noise may not affect fish as much as your fellow anglers may want you to think. Your voice is unlikely to spook or scare fish away.
According to Balcombe, some fish (though certainly not all) do actually enjoy being touched by humans.
In captivity, it's strongly recommended that they should be kept at least in pairs, to provide companionship. If you watch fish in a tank, you'll see that they regularly engage with other fish. It's thought that solitary fish, much like solitary humans, may begin to suffer from depression and lethargy.
You probably already know that if your aquarium environment does not live up to the standards of your fish they are unlikely to thrive. You may be surprised to learn, however, that an environment that is too cramped or dull can actually cause your fish to become angry.
Male kissers will occasionally challenge each other; however, the "kissing" itself is never fatal, but the constant bullying can stress the other fish to death. They often do in fact kill other fish by sucking the mucus off their skin as food, which opens the victim fish up to infections.
While fish do not sleep in the same way that land mammals sleep, most fish do rest. Research shows that fish may reduce their activity and metabolism while remaining alert to danger. Some fish float in place, some wedge themselves into a secure spot in the mud or coral, and some even locate a suitable nest.
Municipal/Tap Water
Most municipalities treat drinking water with either chlorine or chloramine for disinfection purposes. Chlorine is extremely toxic to fish and needs to be completely removed before the water comes in contact with fish. Chloramine is chlorine bonded to ammonia, both of which are detrimental to fish.
Toxins. Agricultural runoff, sewage, surface runoff, chemical spills and hazardous waste spills can all potentially lead to water toxicity and fish kill. Some algae species also produce toxins.
For fish, that title goes to manta rays. They're giant, charismatic and basically geniuses. Mantas have huge brains — the biggest of any fish — with especially developed areas for learning, problem solving and communicating.
Fish have long been known to communicate by several silent mechanisms, but more recently researchers have found evidence that some species also use sound. It is well known that fish communicate by gesture and motion, as in the highly regimented synchronized swimming of schools of fish.
Each fish gets food especially for them – some eat plankton and fruit flies, others eat seeds and vegetables; some fish hunt for their food, others forage for it. Once they've eaten, fish spend their days guarding their homes, and at this time of year, breeding season, they spend lots of time competing for mates.
Fish living in the deep sea manage to navigate in complete darkness. It's not strictly 'seeing' but fish have rows of pressure-sensitive organs running down each side of their body called the lateral line, which allows them to sense nearby animals from the pressure changes in the water.
Fish-keepers sometimes see their pets 'glass surfing' – swimming repeatedly up and down the glass of the tank. This could be the aquatic equivalent of the pacing of a captive tiger that's bored from a lack of stimulation. But the fish could also be stressed from an overcrowded or unfamiliar tank.
But can fish hear? Fish don't have ears that we can see, but they do have ear parts inside their heads. They pick up sounds in the water through their bodies and in their internal ear, according to the National Wildlife Federation.