Zombie Biology

Even The Undead Gotta Obey Physics!

Everyone's favorite zombiephobe Eric SWG posted something on FB the other day that got me re-thinking about a topic that's been stewing in my noodle for quite some time...

Eric said (and I quote...)  "...... "The nucleotide monomers are linked together by condensation reactions forming a repeating sugar-phosphate backbone with the nitrogenous bases sticking out from this backbone. The bond holding the nucleotides together is called a phosphodiester linkage."...... good lord......"

Good Lord, indeed!

That bit of molecular biobabble is describing the chemical bonds that hold DNA together, btw.  What does that have to do with zombies?  Nothing, but it did get me thinking about the various chemical reactions that keep the human body humming along.

Now, on to zombies...

Zombies are, according to legend and lore, dead.  Dead as fried chicken.  Which kinda begs the question, if they're dead, how are they able to lurch around and seek out brains for nourishment?

Now, all you zombie fans are bouncing up and down, waving your hands shouting "OOOOoooo!!   Ooooo!!  I know this one, Mr. Kotter!!    It's a VIRUS!!!"

OK, so it's a virus.  Big effin' deal.  That explains the contagion.  It does jack shit explaining reanimation, locomotion and digestion!

Again, according to legend and lore, once you're bitten by a zombie, or somehow you get zombie bodily fluids co-mingled with your own, it's just a matter of time until the zombie antibodies or spores (or whatever they are) spread through your system and cause massive failure of your organs.  Essentially, you're dying of an overwhelming infection.

So, now you're dead.  No brain waves, no heartbeat, no respiration.  There will continue to be some cellular activity, at least until the cells run out of fuel or get clogged up with waste and cease functioning.

Supposedly the zombie cells/virii/spores will take over your body, brain & organs and you'll re-awaken with an intense need to shamble about feeding on brains and spleens and pancreii.

Still, how does a dead body get up and operate??

I'll give you one freebie, just 'cause I'm cool like that...

Let's say the zombie virus has occupied and set up shop all along the nervous system.  It's packed untold millions of spores in your brain, and each nerve ending is just riddled with zombie cells.

In a normal body, electrical signals are sent from the brain and pass along the nerves.  Signals jump along the axons, dendrites and neurons, it's a cascade of positive & negative ions, all of it soaked in potassium and sodium and wrapped in a myelin sheath.

I'll grant that it's in the realm of possible for an invasive virus or spore colony to set up a network along existing nerves, and to hook up all those spores in the brain in a series like a set of marine batteries.  Put enough of 'em in the circuit, and you can generate enough power to push signals down the line.

So, I'll give you that one.  You can have the zombie brain tell the zombie body "GO FORTH AND SHAMBLE AROUND!!!"

However...  You still gotta move that body.

Muscles operate by contraction and relaxation, signalled by the nerves, and powered by adenosine triphosphate.  You get ATP through the oxidation of fats and carbohydrates, brought to the cells via the blood in the form of simple sugars.  I don't even want to get into glycolysis or the Krebs cycle.  Look it up if you must...

The cells do store a substance called glycogen, which it will burn in the absence of ATP, but once that's used up, that muscle is done working for good.

So, you can move that zombie, but just for a very short while.  Also, there's not many carbs to be had in consuming brains...

The next big issue with being dead, is, well, you're dead.  Once your cells stop respirating and replicating and digesting and excreting and doing all the things that healthy live cells do, they tend to break down in short order.

You rot from the inside out, starting in the gut where there's already a good supply of bacteria and chemical solvents.   Gravity takes its toll, as fluids soak downward.  Individual cells burst, or lyse, and what doesn't rot dries out.

Depending on environmental conditions, you either end up as a dry husk over a wet spot on the floor, or a fatty schmear that's partially saponified on top of your skeleton.

My point is, you don't have too long as a zombie before you just sort of fall apart as a matter of course.

So, no, a virus or a spore infestation just isn't enough to get a plague of undead wandering about.  There's got to be another mechanism at play.  It's likely a zombie in real life would just lay there and moan for brains for an hour or so before running out of juice.

That's got to make Eric very happy indeed!

Feel free to theorize in the comments!