The reproductive behavior of living things is diverse. Some are male when they are born, and become female in later stages of life. There are also some that depend on whether they can successfully court a mate. If they succeed, they have completed their mission. No. Successfully employed and transformed into a female.

The anglerfish is a deep-sea fish with an ugly appearance. Its body tissue is relatively soft and its bones are relatively thin. It is adapted to the seawater pressure of the deep sea. However, due to its own characteristics, it swims relatively slowly, so it mostly hunts in stealth mode. , after the prey reaches the mouth, the mouth opens wide to form a vacuum environment to suck the prey in. Moreover, the size of male fish is much smaller than that of females, only about 1/50 of the size of female fish, which is not conducive to hunting, so their main task in life is to mate.

At first, scientists only found that the female fish could not find the male fish. Later, they found that the female fish had inexplicable lumps on her body. Later, research found that it was actually a male fish. After they met the female fish, they sucked themselves into the female fish. On the body, the surface tissue of the female fish is bitten and parasitized there. Eventually, the body structure shrinks, leaving only the spermatic cord, testicles and other structures in order to fertilize the female fish. What's even more amazing is that if they fail to find a female fish, they will transform into a female fish themselves, and then they can grow larger and be more convenient for hunting. In this way, they pass on their genes.

The eel is also a species that can switch between male and female. Monopterus eels are female from the embryonic stage to the first sexual maturity. The body length of female eels is less than 35cm. Their gender changes after laying eggs. eels with a body length of 39cm or more are mostly male, so according to the characteristics of the caught eels, The length can basically determine their gender, but this example does not apply to the question of male to female.

There are many fish that can change from male to female in the ocean. They generally live in places where food is scarce or their own strength is weak. The number of fish that can be supported by food is limited, so males and females meet each other throughout their lives. There are not many opportunities. Similar to anglerfish, some fish with relatively weak strength mostly survive by chance, that is, they continue the population by laying more eggs. The difference between male and female is that there are genes in the cytoplasm of female fish egg cells, and through male-male conversion, More genes can be passed on to future generations, and oysters, a marine animal, continue to change sex between males and females throughout their lives.

Scientists have found that species that can switch genders are affected by some chemicals in the environment, which can hinder the formation of hormones, allowing them to grow new sexual systems. This also shows that The somatic cells of those animals have a relatively low degree of differentiation, maintain a high totipotency, and can develop into other tissues.