Goldfish (koi) is an exquisite species domesticated over centuries to display colorful patterns and vibrant hues, making them popular choices in home aquariums and ponds as well as outdoor ponds with larger outdoor environments. Though often mistaken as goldfish in commercial venues, most stock usually found there consists of common carp or mirror carp that have been genetically modified to reach larger sizes while using less energy for growth in body scales.
Goldfish, belonging to the order Cyprinidae, can be found worldwide in freshwater environments like rivers, streams, lakes, ponds and reservoirs. Omnivorous bottom-feeders that use their pharyngeal teeth to crush food, these fish are highly tolerant of turbid waters as well as temperature fluctuations and low levels of dissolved oxygen; in captivity they make popular pets that can even learn to recognize Bach, Stravinsky or other classical pieces as stimuli for feeding time!
Goldfish (Carassius aureus), commonly seen in ponds and homes today, owe their golden hue to a gene mutation within crucian carp (Carassius aureus). Goldfish first originated in China over a millennia ago before being selectively bred for beauty over the following millennia. Koi carp are subspecies of armur carp that have been genetically altered to display vibrant bodies with intricate patterns; otherwise left breeding with wild carp they would quickly revert back into standard common carp colors seen today.
