An Imagination Is a Terrible Thing

I have been reliably informed that there is a stingray in this pictureMy three-year-old son and I were walking along the dock.  His mother had gone on ahead to take pictures of the stingrays gliding through the shallows.

Son: "What's that?"  *points to dock*Me: "Don't step on that, kiddo.  That's bird poopies."Son: *takes exaggerated steps around a massive clot of pelican poop*  "Birds pee on there, too."Me: "Well, I don't know if they pee on there.  I don't even know if birds do pee."Son: "They did.  Lots of time ago.  They pee on there."Me: "Okay."Son: "Lots of time ago birds have lots of penises."Me: *caught between dismay and fascination* "Oh?"Son: "Yeah.  They have lots of bad penises and pee lots of time ago."Me: *struggling with the mental image of a multi-penised bird soaring above, micturating on the dock* "Uh, okay."  Son: "Yeah!"  *runs to catch up to his mother*
Nobody told me that parenthood would be like this: peeing prehistoric penis birds.  Lord only knows what other strange beasts lurk in the soup of his imagination.  
(As it turns out, birds don't pee.)