Goldfish - incredible eyesight

A goldfish is the only animal that can see infrared and ultraviolet light.

Kingdom: Animalia
Phylum: Chordata
Class: Actinopterygii
Order: Cypriniformes
Family: Cyprinidae
Genus: Carassius
Species: C. auratus
Subspecies: C. a. auratus/C. a. gibelio

Goldfish are one of the most common types of fish. They come in different varieties such as Ryukin, Fantail, Oranda and many others. Some goldfish look like they have bubbles of skin covering their eyes. Goldfish can live to be 5 to 10 years old. The average goldfish lives to be around 4 years old and can grow to be 6 inches plus. Goldfish originated in China with several hundred varieties developing over the years. They arrived in the United States somewhere between the 18th and 19th century and have became the most common pet found in households today! They have been kept as pets longer than any other species of fish. Although there are many varieties, all goldfish actually belong to just one species: Carassius auratus. Because of this, goldfish are similar in their behavior, required care, and habits. Goldfish are not tropical fish; therefore, they do not require tropical temperatures such as some fish with temperatures of 80F and higher.

Goldfish are quite intelligent and will recognize the person who feeds them, research show that goldfish have a memory-span of at least three months and can distinguish between different shapes, colors and sounds. They will show they know you by swimming rapidly back and forth when you are near the tank or splashing. Goldfish like to play and benefit from the exercise, so having two fish is better than one. There are several varieties of goldfish; however, they all stem from the original stocks developed by Chinese, Korean, and Japanese breeders. Names are sometimes a hard thing to decide on due to the fact that different cultures call the same fish by different names. Goldfish come in many variations with different colors, single-tails, double-tails, various body shapes, head shapes from pointed to square, and various other mutations such as telescoped eyes.

Goldfish Vision:

Vision that is seen in the goldfish may not seem important to many people, but it is actually quite fascinating in that it is much more developed than most people would expect it to be for the size and apparent intelligence of the creature. Overall, goldfish have developed full-spectrum vision so that they will be able to see the micro-flashes of static electrical charge and bio-luminescence that appear when a creature hunting with sonar sends sound waves through waters rich in micro-fauna in order to search for its prey. This full-spectrum vision has also proved to be very effective in sensing many and various tell-tale signs that come from the bow-wave that a rapidly moving predator makes as it cuts through the water.

Goldfish, in particular, have been widely used as a model system for the study of color vision. The goldfish retina contains rods and four cone types in juveniles, three cone types in adults. The majority of goldfish retina ganglion cells have center-surround organization and many are wavelength opponent goldfish evidence photopic spectral sensitivity functions reflecting both wavelength additive mechanisms and wavelength opponent mechanisms. Goldfish wavelength discrimination has been reported in many studies and found out to exhibit color constancy. the goldfish first developed full spectrum vision in order to see the micro-flashes of bio-luminescence and static electrical charges that tend to discharge when a sonar-hunter sends sound waves through micro-fauna rich waters in search of prey. It also proved effective in sensing various tell-tales that result from the bow-wave of a fast moving predator... Only later did they realize that they could track submarines, intercept trace reflections of communication lasers that took bad bounces of atmospheric interference, and even decode the ultra-faint eminations that are shed of trans-oceanic communication cables, and so much more.