Of fish and jellyfish

My nearly five-year old is learning about vertebrates in school. When we were doing his homeplay the other day, I was seriously impressed with the speed with which he rattled off names of mammals and reptiles (writing those names down took a bit longer, but that gave me time to access my memory banks to find out if turtles were indeed reptiles or not).

Then we got to birds, and my problems began – he insisted that bats were birds, because bats could fly. It was less difficult telling him that bats were not birds (birds have feathers on their wings, do bats have feathers?), than convincing him that bats were mammals (when even I haven’t seen bats suckle their young, isn’t it asking for a leap of faith to ask him to believe that?). Finally, he gave in – perhaps seeing Bruce Wayne with his mother before Bruce Wayne became Batman had something to do with it, but I am not complaining.

Fish was a lot more difficult. I was anticipating problems with whales and dolphins – they look like fish and swim like fish, so why are they not fish? I knew we had seen a clip where the baby dolphin was suckling the Mamma dolphin, and was thinking of reminding him of it.
But the problems came from an unexpected quarter. He insisted that jellyfish was a fish. I tried telling him that just because jellyfish had fish in its name, it did not become a fish, but his argument was a bit more profound – but jellyfish lives in water, it has to be a fish. Ditto, starfish.

There were lots of explanations centered around how fish had fins and jellyfish and starfish did not, and about how fish laid eggs but jellyfish and starfish did not, and of how fish had bones but jellyfish and starfish did not. Information overload! All that he had been taught in school was that fish were vertebrates and fish lived in water.

I know for a fact that my son trusts his mother, and he will eventually accept what she tells him including seemingly unbelievable stuff like jellyfish and starfish not being fish. But I do wish it had never come to that.
Why confuse the kids by introducing the concept of jellyfish and starfish, when you know you don’t have simple explanations for obvious questions like why they are not fish. With so many species to choose from, why choose two that are sure to confuse the kids?

I guess I should just be happy that his teacher hasn’t introduced him ladybirds – they have wings and they fly, why then are they insects and not birds. Specially since they do not bite or spread diseases like the other insects do.