Is amphioxus a fish?

Amphioxus, a cephalopod branchial subclass, has no spine and is not a fish. Amphioxus is a humble animal, but it is an animal in the middle of evolution from lower invertebrates to higher vertebrates, and it is also a model of vertebrate ancestors. The feeding and excreting functions of amphioxus are all invertebrates, but the vascular system, respiratory system, nervous system and embryonic development all look like vertebrates.

Amphioxus is an animal suitable for warming the ocean. Half of its lower body is buried in the sand, and only its front end is exposed. During the day, half of its body is hidden in the gravel, swaying under the sunlight, and relying on the current to bring plankton, diatoms and plants to it as food. This passive feeding method.

It shows that its level is low, that is to say, it is lower than vertebrates in evolution; It is only active at night. At this time, it left the sand nest and bounced to the water like an arrow. Once disturbed, it will swim back to the beach nest. Amphioxus swims in a spiral way.

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Amphioxus is listed as a national second-class protected animal in China. It belongs to chordates, feeds on diatoms and sea snake tail larvae, and lives in a clean and breathable coarse sandy seabed area. The word "Wenchang" of amphioxus originated from "Emperor Wenchang". According to the Records of Tongan County, Xiamen, "Amphioxus, like eels, are as thin as silk and are produced in Xixi offshore", hence the name Wenchang Dijun's birthday.

/kloc-Valevski, a Russian embryologist in the 20th century, wrote The History of Amphioxus, which provided a strong basis for Darwin's theory of evolution, and his research achievements were highly praised by Darwin. Amphioxus is mainly produced in Xiamen, China, which established a national amphioxus nature reserve in 199 1.

People's Network-With so many living fossils, the resource of Maoming amphioxus is as high as 20.4 billion.

Baidu encyclopedia-amphioxus