A goldfish shares a lot of senses with humans, and learns how to use them with their surroundings.
Vision
If you look closely at you fish's eyes a main difference between
their eyes and our eyes, are that they don't have any eyelids.
But, you might not see is that they don't have an iris. An iris
is apart of our eyes that changes size to let more or less light
into the eye. But, on the other hand, fish do have retina. Retina
is the part of the eye to help our eyes adapt from darkness to
daylight, but for goldfish, it works very slow and it takes a lot
time to adjust. Have you ever notices, whenever you turn on you
tank light (IF YOU HAVE AN TANK LIGHT), that your fish swirms to
look for a place to hide from the light. They do this because
like I said, they don't have any eyelids and an iris. But, as
time goes by, their eyes adapt to the condtion. So it is a good
idea to keep your aquarium weell-decorated with either plants or
figurines to proivde your fish some shelter. If your fish get so
scared, they might even become more prone to disease and injury.
If you already visited the Basics Page, I told not to keep your
light on only when needed, to help their vision care, and the
need for sleep. People have found out, that goldfish see colors
and shapes, but they cannot see distance very well. Goldfish are
nearsighted, with limited front vision. But, luckily for fish,
vision is to a very important sense for them. Different types of
fish have different eyes, because of mutations and leaves some
fish looking only in one direction. But, this doesn't have a big
affect on their senses and actions.
Smell
In fish, the sense of smell isn't that good or sophisitcated, but
it is one of their more important senses. Fish use their sense of
smell to communicate with others and their environment. Their
sense of smell is also used to detect food, it plays an important
role in sexual activity, and it even plays a role in a fish's
school groups. The smell organs, like in humans are their
nostrils. Fish's nostrils do not connect to the mouth or throat.
Goldfish mostly have two nostrils, one on each side of their head
or snout. Water enters and leaves the nostril through the same
opening. While this may seem inefficient, it does work well. Like
to humans, smog and air pollution damages our sense of smell, in
a fish's case polluted water damages this important sense that
they need so much, since it injures their sensors. Foul water,
can even make a goldfish disoriented and difficult for it to find
it's food.
Taste
Goldfish have many taste buds. They are located all over the
mouth. A goldfish used its mouth to explore for food. Like in
other animals, the sense of taste and smell work together, helps
goldfish locate food.
Touch
The goldfish has a keen sense of touch. But, their sense of touch
isn't really that developed. Whenever someone thinks of goldfish
have sense of touch, they might ask, "Do fish get
hurt?" Well to answer that question, fish react negatively
to negative stimuli, but the reaction may be an uncontrolled
reflex, like ones we get when we get those knee jerks during a
physical.
Hearing
As you may also notice, when you look at your fish, is that they
don't have any ears. So, how do they hear and take advantage of
the sense of hearing? Well, do you ever notice, whrn you tap on
your tank, your fish go wild. So this one way we know that fish
some how have a way to hear sound waves. Fish actually make
grunting and squeaking noises during mating, feeding, or during a
rivalry. These noises are heard by other fish to react
appropriately. Unlike people, fish hear in different ways. The
main hearing organ is in the fish's head. It is an inner hear,
that provides balance of sound. But, their hearing organs have no
cochlea, but they have a otolith, a hard stone, that transmits
sound waves throughout their body. Some goldfish have a series of
bones, called, the webarian ossicles transmit waves in it's
bladder and sends a message to the otolith.
Lateral Line
System
Goldfish detect pressure changes produces by sound and
vibrations. This is done by the lateral line system. Goldfish
have a system of nerves, called a lateral line. It runs on the
side of the body to the head. The whole system is connected to
the brain with an auditory nerve. Lateral line systems can be
damaged with water pollution, like I said in the sense of smell,
it disorients the fish.
