Scyphozoans: Two Animals in One

Scyphozoans are a type of jellyfish that you have probably seen in an aquarium.  They float by slowly in the ocean and use stingers at the end of their long tentacles to kill fish and plankton to eat.  If you are swimming in the water with them you should be extra careful.  They pack a tremendous punch in those tentacles!  But there is something strange about them that you probably don’t know.  When these jellyfish produce babies, those babies will swim down to the bottom of the ocean and live attached to the ground.  The babies of the jellyfish aren’t jellyfish at all.  They are tiny animals on the seafloor called polyps.  The polyps resemble tiny corals.  When those polyps reproduce their babies will swim up to the surface and grow into jellyfish.  That is like if you had a child and it turned out to be a dog.  But then when that dog gave birth it grew into a human like you.  And then your grandchild would have a baby that grew into a dog again.  What a weird way of life for that scyphozoan!