How jellyfish reproduce

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Original: https://www.livescience.com/45975-animal-sex-jellyfish.html

Jellyfish have gelatinous bodies and strange legs, and this creature seems to have little resemblance to other organisms on Earth. So is their reproductive process just as unique?

There are nearly 4,000 species of jellyfish in the world, and some species do not have the typical signs of jellyfish (gelatinous substances floating freely in water with antennae), but they are also jellyfish. The last species that can grow into typical jellyfish belong to the bowl jellyfish, which have appeared as early as the Cambrian period, such as the sea moon jellyfish, the cubic jellyfish.

Jellyfish generally move in groups, but during the breeding season, their mating methods are not very romantic. Male jellyfish swim and throw their sperm in the water. Sperm are released from their multifunctional mouth, which performs the three functions of eating, excretion and reproduction.

Female jellyfish begin to collect sperm floating in the water, some female jellyfish use the ovaries near the cloaca to absorb sperm directly to form fertilized eggs; other species of female jellyfish need to eat sperm and then let the eggs fertilize.

In 2005, marine biologists discovered a cubic jellyfish, Copula sivickisi, which has the ritual of "dancing" before mating. The male jellyfish will use their own tentacles to pull the female jellyfish's tentacles, and then they will pull each other around for a while, and then when the time is ripe, they will close the distance. Male jellyfish will excrete sperm sacs, pick them up with their own tentacles and hand them to female jellyfish. After that, the two will go their separate ways, and the female jellyfish will eat sperm sacs to breed offspring.

The female of this cubic jellyfish will stop mating with other opposite sexes when her stomach is filled with sperm, while the male will stop mating after using up the savings of four pairs of testicles.

Jellyfish larvae gradually grow into floating wave larvae that can swim freely. In some jellyfish species, the floating wave larvae can grow into jellyfish complete bodies, while some floating wave larvae will find a fixed attachment to settle down and become cylindrical strips of water insects.

Water worms can continue to develop into jellyfish complete bodies, and it is also possible to continue to reproduce in the water worm rest state. However, water worms can only reproduce asexually, that is, to create a clone of themselves.

Clones of water worm breaths can continue to attach to solid surfaces as water worms breathe, or they can grow into baby jellyfish and then become adult jellyfish.