When I was *very* young (though it continued to a worrying age) I was convinced that a zebra was a kind of flightless bird.
I know my dog, Palmer, spoke English, he was just really quiet.
When I was around 4 my sister told me the "truth" that my real parents were rabbits, and that my dad found me in the backyard whilst mowing the lawn. She said mom and dad only took me in because they felt bad about almost mowing me over. For years after I'd see a rabbit and wonder if it was a relative. Damn sister.
i used to believe that sausages were to pigs as eggs are to hens
When I was younger, I would sleep at my grandmother's house, in the guest bedroom. She told me not to sleep under the window, because of the "terrible draft". For the following few years, I avoided that bed fearing that the "terrible giraffe" would stick his head in and hurt me somehow.
"Lions, and Tigers, and Bears, Oh My!"
My little cousin Melissa used to love the Wizard of Oz. Well, when we took her to the zoo one time, she kept asking to see the "Oh My's". It took us such a long time to figure out that she thought Oh My's were a real animal from the song in the movie!
I took 'Peter Cottontail' a bit seriously, and thought that all cotton came from rabbits' tails. The first time I saw a bag of 100 cotton balls, I was horrified. Then I figured they must shed them or have them shaved off like sheep's wool. Learning about the slaves and cotton in the South set me straight.
I used to believe that we had invisible giraffes in our house. Whenever my mother said, "There's a draft in here," I used to think that she was saying "giraffe." I'd look and look and couldn't see a giraffe. The idea of something that large wandering around the house without me being able to see it was quite frightening.
My Dad used to tell about sidehill gougers, a moose looking elk with legs shorter on one side than the other, the better to go around hills. If they went in the valley they would fall over and die. They lived on the hills of SE Ohio. Courting sidehill gougers would burrow under the hills with corkscrews that grew on their noses at puberty (like antlers), and they could walk on the round sides of the tunnels, and pop up on an unrelated hill. There were clockwise and counterclockwise gougers, and they could not intermarry, or 75%their kids would have cross dominant legs, short and long on the same side, and be unable to walk and survive. I was very, very disapointed to find this was not true. I am glad to see others had the same story told to them in their childhoods.
I also thought cows were girl horses, and cats were girl dogs, that all horses and dogs were boys, and that chipmunks thought they owned your house and were hitting you up for rent when they chattered at you.
When I was little I filled my pockets with rabbit droppings because I thought they were special, shiny, black pebbles.