Why?

Why are children so fascinated with poop? And it's not a learned fascination either...it must be intrinsic, because it begins so young. For instance, my darling son Jude decided to take off his diaper, while his naive mother thinks he's actually taking a nap (side issue: why are disposable diapers so easy for kids to take off? Couldn't they have put like a sailor's knot on it to keep them out? I guess that's what I get for going the "easy" route with disposable diapers). Then he proceeds to poop all over his crib; I'm talking like 4 different piles of excrement. And this is when he decides it's time for a sleep, so he sleeps. On his poop. When I hear him wake up, noticeably early from his nap, I hear him saying, "Poo Poo"...and that's when I see the smeared poop all over the crib, and him. I'm talking caked into his hair. What gets me is that I don't think it was the poop that woke him up; I believe it was because he peed on top of it all. And, of course, he can't sleep in his own pee. That's just gross.