Evolution history of goldfish:
Goldfish in the wild state are green, brown or gray, but there are also various goldfish varieties, such as black, color, gold, white, silvery white, three-tailed, dzi beads or no dorsal fin. Over the centuries, the selection and cultivation of this abnormal individual has produced more than 125 goldfish species.
Omnivorous, feeding on plants and small animals. Small crustaceans are also eaten during breeding, and chopped mosquito larvae, grains and other foods can be used as supplementary feed. Oviposition takes place in spring and summer. In this season, the body color begins to become bright, the female fish's abdomen expands, and the male fish's gill cover, back and pectoral fin can be idolized with the size of a needle tip. Eggs attach to aquatic plants and hatch for about a week. It is known that the life span of ornamental goldfish is 25 years, but the average life span is much shorter. In many parts of the eastern United States, goldfish that have escaped from parks and gardens have become wild. After being wild, it will return to its original color and grow from 5 ~10cm (2 ~ 4 inches) to 30cm.
Goldfish is an ornamental fish that our people are happy to raise. It has become a natural living work of art because of its peculiar posture and gorgeous colors, so it is loved by people. According to historical records and modern scientific experiments, scientists have found out that goldfish originated from wild crucian carp, which is widely eaten in China. First, it changed from silver-gray wild crucian carp to red-yellow golden crucian carp, and then from red-yellow golden crucian carp to different varieties of goldfish after domestic rearing in different periods.
As an ornamental fish, red crucian carp was recorded in China as early as the Jin Dynasty (265-420). Red and yellow crucian carp began to appear in the "release pond" in the Tang Dynasty, and golden crucian carp began to appear in the Song Dynasty. People began to raise goldfish in ponds, and goldfish appeared in two colors: white flowers and spots. In the Ming Dynasty, goldfish moved into a fish tank. In animal taxonomy, it belongs to vertebrates, cephalopods, jaws, fishes, eustoma, CYPRINIDAE, CYPRINIDAE and Carassius. Goldfish and crucian carp belong to the same species and use the same scientific name (Carassius auratus) in science.
Fish is closely related to human beings. As early as the Stone Age, people lived on fishing. More than 3,200 years ago, there were records of fish farming in China (according to Oracle Bone Inscriptions unearthed in Yin Ruins). Because of the long-term fishing and fish culture, there are many opportunities to contact with fish, which means that there are many opportunities to observe and understand fish, so it is easy to find the mutated species in wild fish, especially those that turn golden yellow or red, which are more likely to attract people's attention. At that time, people collectively referred to golden or red fish as "goldfish".
Li Shizhen, a great herbalist in Ming Dynasty, wrote in Compendium of Materia Medica: "There are several kinds of goldfish, such as carp, crucian carp, loach and turtle, which are extremely rare, and the golden crucian carp is durable, which was unknown before" ... There are four kinds of fish called "goldfish", that is, crucian carp whose color turns yellow and red. Later, due to the independent breeding of golden crucian carp, the change is getting bigger and bigger, so
The hometown of goldfish is Jiaxing, Zhejiang, Hangzhou and Zhenping, Henan. According to the research of Japanese scholar Ishii Matsui (1934), the earliest record of China goldfish being introduced into Japan is 1502. Goldfish was introduced to Britain at the end of 17, and by the middle of 18, two-tailed goldfish had spread all over Europe and America in 1874.
The external morphology of goldfish is very different from that of crucian carp, and there is almost no character without variation. Its posture changes include body color, body shape, scale number, scale shape, dorsal fin, pectoral fin, ventral fin, anal fin, caudal fin, head shape, eyes, gill cover and nasal septum. Here are the changes of body color, head shape and eyes.