On one level, I understand film's reluctance to include this explanation on camera. After all, how many episodes of 24 included a 10-minute scene of Kiefer Sutherland on the crapper anyway, just pensively staring at his hands, wishing his unreliable insides would cut him some slack so he could go defuse a nuclear president, or whatever it was he did on that show? You try to avoid poop scenes because, in the words of Hitchcock, they're fucking silly. Weren't expecting that, were you? Neither was the cast of Vertigo.
A zombie movie doesn't need to completely devolve into a poop joke to take a moment to account for the simple problem of zombie biology. If they consume flesh, it needs to go somewhere; it's the same deal when I eat Taco Bell. It really is. World War Z made reference to their stomachs exploding, if I recall correctly, but no one on camera has addressed it. At some point, all that tasty man souffle is going to go somewhere, and it's not going to be pleasant. Not at all. Incidentally, I immediately regret the use of "souffle" in that metaphor, as it makes it sound far more sexual than I intended. You'll probably now wonder why I didn't bother to change it.
Why is this question important? Am I a fecalphiliac? Do I have an obsession with butts? This isn't about me, but I will accept butt photos and/or detailed descriptions if you have them handy. It's about a fictional world in which the primary danger to the very existence of humans as a species is a thing that uses eating as its chief weapon. There should be a stunning amount of zombie poop all over the world.
I'll concede to start with that not every zombie flick even wants to address this. But some do, and they leave a big question hanging in the air. The Walking Dead has brought this up a number of times, and of course it was a big part of the not-quite-zombie movies 28 Days/Weeks Later. Can you cure a zombie?
Certainly it's reasonable to assume you'd want to get rid of whatever it is that makes zombies, but after someone dies, and is rotting, and has eaten people, and maybe has been shot a few times, and is missing a foot, and has no skin on its torso, what is it exactly you think might be getting cured? How did the zombie apocalypse instill so much new faith in medical science in you?
As far as I know, right now, you could still potentially die from dysentery in many parts of the world. If medical science has not progressed to the point where we can prevent people around the globe from dying of pooping too much, how likely do you think it is that there's a doctor somewhere who just perfected a treatment for having half a head and trailing flaming intestines behind you? Imagine waking up in a hospital after months of being a zombie and eating people and being rotten only to be told you'd been a zombie since last year and you sort of don't have a leg now and you ate a football team. Why would you want to do that to someone?
If I were to make up a number off the top of my head, and I will because I'm numerically bold, I would say that about two-thirds of zombie movies don't take the time to explain zombies. That's not a mistake, it's kind of a zombie trope. George Romero purposely ignored the cause of the zombie phenomenon, and really, it was unnecessary when you think about it. If you were being attacked by zombies, you probably would be less concerned with why they exist and more concerned with ensuring that the last thing you see isn't your neighbor chewing off your genitals.
So, very often, the beginning of a zombie story is unwritten, and that's cool, because it's not always relevant. But no one has ever finished a zombie story. This is potentially due to the fact that it would be a curious mix of horribly uninteresting and horribly depressing if it did happen, but it's still a worthy thing to wonder about. Hell, George Romero has spanned four movies (more if you count things like Diary of the Dead, which you shouldn't) and decades of time and still hasn't gotten to the logical conclusion of all zombie fiction -- the end of humanity. If zombies kill everyone, then what happens?
Land of the Dead was just ridiculous, and the best it could offer up was walled-up cities and the decrepit countryside full of undead people in costumes and one ridiculously crafty zombie gas station attendant. But if there was a World of the Dead to follow it up, would it literally just be zombies standing there? Is that the end result of the zombie apocalypse? That's the worst end of the world ever -- a planet of guys loitering around drooling black stuff on themselves and occasionally moaning at the breeze.
For more from Ian, check out 7 Safety Products (for the Incredibly Paranoid) and 10 Retarded Money Saving Tips (People Are Actually Trying).