Starfish are marine animals. There are many kinds of starfish, which are widely distributed in various sea areas of the world, among which the North Pacific Ocean has the most kinds of starfish. They can be seen from the intertidal zone to the water depth of 6000 meters, and usually live in various sediments, but they are rare on the soft mud bottom. It is a kind of echinoderm, which has a soft body and can move with tube feet. At the same time, it can also be used for hunting and foraging.

1. Dioecious: Most starfish are dioecious. After they mature, females will discharge eggs and males will discharge sperm. After sperm and eggs combine, fertilized eggs will be formed, and then they will become starfish after metamorphosis and development. It is worth mentioning that starfish do not need to mate, so the generation of offspring is completely random, but its ovulation amount is very large, reaching 2.5 million eggs.

2, hermaphrodite: In addition to dioecious starfish, some starfish are hermaphrodite. These starfish usually become males first, producing male germ cells, and when they grow up, they become females and lay eggs, so that they can reproduce their offspring.

3. Asexual reproduction: Starfish itself has strong regeneration ability, so it can also reproduce asexually. As long as there is one part of the body, a complete starfish can grow. However, in nature, they usually do not need to reproduce asexually.