In your head, in your head, zombie, zombie, zom…
Everybody these days has a zombie survival plan. Mine mostly involves weeping in the
fetal position in the dark? But fortunately or unfortunately, depending on how much you’ve
already sunk into your zombie contingency plan, a traditional, undead-zombie outbreak
is never going to happen, because zombies are physically impossible.
Here are five reasons why.
OK: The conditions of the zombie outbreak set in. Let’s say a space probe returns
from Venus, explodes in the atmosphere and that somehow wakes up all the corpses on the
planet. Doesn’t really make sense to me, but Romero said it, and I believe it, so...
Imagine you’re a corpse, you’re just lying in your coffin, minding your own business,
when suddenly you wake up with a craving for the moist savor of human flesh. Or whatever,
you know.
That hunger you feel suggests your body is still subject to the laws of physics – namely
the conservation of energy. If you’re going to be walking around, chasing survivors and
moaning for brains, all of that activity costs your body energy.
And for energy to be going out of your body, it also needs to be coming back in.
Normally, this happens when a living human body converts chemical energy from food in the process we
know as metabolism.
But an undead creature like a zombie has essentially already declared energy bankruptcy. Obviously
corpses don’t have the working digestive system and metabolism to turn food into usable
energy. A dead body has no metabolism, and thus it can’t really... do ... anything!
But let’s say we just ignore the fundamental energy/metabolism problem, and we just grant
that dead, rotting bodies are able to walk around looking for fresh brains.
We immediately run into another huge obstacle: the weather. It’s easy to forget that living
organisms spend a huge amount of effort protecting the insides of our bodies from the whims of
the weather. Just one example: Thermoregulation.
Thermoregulation means being able to keep your body’s internal temperature within
a certain range, even if the temperature outside is a good bit higher or lower. Thermoregulation
is a form of homeostasis, which just means being able to dynamically adjust variables
to keep the internal conditions of your body relatively stable.
Zombies, having none of these capabilities, better hope the weather is nice, or it’s
lights out yet again. Without thermoregulation, sub-freezing temperatures would crystalize
whatever moisture content is left in zombie flesh, destroying tissues -- including the
all-important and delicious brain tissue.
So: No zombies in winter. Likewise, zombies in a hot, dry desert climate would quickly
see their moisture evaporate, leaving them shriveled, desiccated delicious raisin-corpses.
But, let’s say you imagine your zombie outbreak in very hot, humid, jungle climate.
Everything would be fine, right? Wrong!
Here we get to another problem. Have you ever seen what happens if you leave a piece
of raw meat sitting out for a week in a hot, humid climate, like you do?
That’s right: It’s swarming with flies and smells of rot… that is, if it’s still where you left it when you come
back to check.
Presumably, the same thing would have to happen to a zombie. Having no immune systems, zombies
would almost immediately become infested with microscopic opportunists like bacteria and
fungi, not to mention millions of insects – beetles, flies and maggots, and other
carrion-eating insects. That sounds fun.
These efficient organisms can consume a given mass of dead flesh at an alarming rate. On
top of that, you can count on vultures, dogs, raccoons and other adorable large-scale scavengers
to come looking for their taste as well. I mean, really, every zombie in every zombie
movie should be dragging a train of scavengers large and small everywhere it goes until its
bones are picked clean.
OK, all right, you’re saying, ignore all that. Let’s imagine they can walk, moan
and eat brains in a climate-controlled, scavenger-free zombie wonderland. We’ve pointed out that,
lacking a metabolism, zombies can’t turn food into usable energy. But there’s another
problem with the brain-eating impulse: If zombies lack a functioning digestive system,
they probably can’t ... poop.
The brains have nowhere to go, so they would likely just pile up in the digestive tract
and ferment, which would produce expanding gases, and eventually the zombie’s stomach
might just burst. That's... disgusting.
Finally, I would just like to point out that zombies would probably have a really hard
time finding you. True undead zombies exist in various states of decay, and the soft tissue
of the eyes would be one of the first things to disintegrate as the zombie rots.
This means that most zombies (except maybe the really fresh ones) would have no vision,
and thus would have a pretty difficult time chasing you down. Of course some types of
zombie mythos say that zombies hunt by smell or hearing. Those senses might not become
impossible as fast as vision, but over time, the same general ideas apply.
So, old-school, undead zombies? It’s just never going to happen. But! That doesn’t
necessarily rule out various conditions of mass psychosis or zombie-like infections.
So maybe you shouldn’t scrap your zombie survival plan just yet…
You just might need to adapt it to some kind of mind-stealing murder fungus scenario. Anyway,
what do you think is the most scientifically plausible zombie scenario? Let us know in
the comments! And if you liked this video, subscribe. And of course, if you want to know
more about zombie science, check out 10 Reasons Zombies Are Physically Impossible at Howstuffworks.com!