What senses does a goldfish have?

Two young goldfish

Most fish possess highly developed sense organs: sight, hearing, smell, taste and feeling. Plus the lateral line, which allows fish to detect the most subtle changes in vibration and pressure.

  1. Sight. First observation: fish do not have eyelids (we have them to keep our eyes moist but they’re not necessary when you live in water!) But they do have a retina (which allows light to be accommodated): this absorbs a very large amount of light – which allows certain species to continue to see in darkness when even a cat would no longer see anything – but only adapts slowly to sudden variations (which explains why if we suddenly turn on the light in the tank, without transition, the fish may seem disoriented… especially since they have no eyelids to protect themselves).
  2. Hearing. Can goldfish hear you? Yes, goldfish can hear well: their ears are very different from ours because they are only internal. A series of vertebrae connects them to the swim bladder, which amplifies the vibrations. However, water does not transmit vibrations in the same way as air: sounds circulate faster than in air but are very distorted.
  3. Smell. Their sense of smell is extremely strong and plays an essential role in the detection of food and in sexuality: the nostrils aren’t connected to the mouth and therefore cannot be used for breathing (this is the role of the gills).
  4. Taste. this sense works in symbiosis with smell: fish have taste buds in the mouth, throat and nostrils.
  5. Feeling. Probably not very developed in goldfish since they do not have barbels (unlike their cousin, the carp,) which play a tactile and sensitive role but the fish can feel if they are touched (which we advise against doing).
  6. The lateral line. From the back of the head to the caudal fin, this very visible line allows fish to detect the most subtle changes in vibration and pressure. It is the lateral line that allows thousands of fish to swim in schools without ever colliding; but it is also essential in order to register as soon as possible the arrival of a possible predator, even in the dark.
Points d'interrogationCan fish feel pain?
This is no longer in doubt today …. a recent article on the subject tells us (Alex Kirby, BBC, April 2003): “The first serious evidence of the perception of pain has been discovered by British scientists (. ..) Fish have pain receptors, as we do (…) Scientists have discovered areas on the head of trout that respond to stimuli that cause damage, and have also found that fish show reactions when “they are exposed to dangerous substances. The question of whether or not fish feel pain has long been a topic of discussion between fishermen and animal activists. The research, conducted by a team from the Roslin Institute from the University of Edinburgh is published by the British National Academy of Sciences (…) Researchers, led by Dr Lynne Sneddon, say that the behavioral and physiological reaction of trout after exposure to harmful substances is comparable to that of the most advanced mammals. ”
There are many causes of suffering: exposure to pollutants (ammonia, nitrite, household products), stressful events (please tell visitors to never to tap/hit the glass of an aquarium), injuries….

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