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Fish taste things via specialized taste organs located in and around the mouth. Fish may also be able to detect taste via additional organs on their body. A number of species, such as catfish, have barbels (commonly referred to as whiskers), or thin protrusions emanating from the mouth area. These are very sensitive to taste.

Fish smell (that is, they are able to) via nostrils on either side of the head. Nerves connect the nostrils to the brain and allow the fish to search for food. Some fish, most notably sharks, have highly refined senses of smell and rely on it more than they do eyesight to find food. Some fish use their sense of smell to find particular waters. Anadromous fish such as salmon live in oceans but always migrate to the stream in which they were born. Their senses of smell allow them to detect the odor of their home stream.

What Fish See and Don't See

Fish see things very much like humans see things, although there are some important differences.

First, with the exception of some sharks, fish don't have eyelids and tear glands. Because the fish is in constant contact with water, there is no need to rewet the eye and clean it.

Second, most fish can't regulate the size of their iris, which is the colored ring on the eye. The human iris can widen or shrink to adjust to the amount of light, leaving just a dot in the center when the light is bright, or exposing the whole lens in dim conditions. Fish, therefore, must move to different areas of their environment to adjust to the amount of light in the water. (Of course, light under water never reaches the same brilliance as does light above it.) This is why fish rarely expose themselves to bright sunlight.

Third, the lens of a fish is round (when looking from the side), not disk-like as in humans. Fish focus on objects by altering the position of the lens, instead of changing its shape, as we do.

Fourth, because fish have eyes on either side of their head, they can see objects to either side of them simultaneously (although most fish can't focus on the same object with both eyes). This also means, however, that fish have a blind spot directly in front of their heads, because the line of vision from each eye intersects at a certain distance in front of themfrom a few inches to a few feet, depending on the fish.

Fifth, some fish species are farsighted, some are nearsighted; others have no problem focusing on both distant and close objects. This last group can focus their eyes independently on different objects at different ranges as well. Authorities agree that the various vision capabilities of fish depend on the environment and habits of the particular species. For instance, a bottom-hugging catfish has no need to see objects at a long distance; the fish is suited to living and feeding in dark and often silty waters. This makes perfect sense

Fish Recipes

Fish Recipes

This is a great collection of delicious fish and shell fish recipes that you will love.

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