In order for any undead or living organism to move by itself, via muscles, must use various nutrients to survive, I believe that the virus that inhabits zombies may perhaps break down cellular matter of consumed cells to form food for said zombie. Since without it the zombie may just rot away, and the digestive systems of the zombies are not functioning. Perhaps the virus spreads the food through the body somehow?
Zombies are like us, the are just partially human creatures with similar anatomy. They need the same things we do, nutrients essential for life.
The dead crave human flesh for the simple fact that they simply want to satisfy their instinct..to fill in the appettite for carnal pleasures. I heard a preacher once say that the human body is always craving carnal pleasure but that the human soul must fight against such temptations. So what happens when people die, their soul is gone and only a living corpse remains.
Since its a virus causing the zombie, its a possibility the flesh eating is merely a result of the virus. Certain viruses and paracites have been known to change the normal behaviour of their hosts. Rabies for example promotes aggressiveness and paranoia, whilst building up clots the virus within the salvia glands. This is because the virus will have a greater chance of being passed on through the bite.
So it could well be that the infected brain of a zombie is being driven by a similar simple command.Since zombies don't digest anything it can't be about nourishment. So thus the only logical answer to me is that its a behavioural imprint on the brain to feed and spread the infection.
Can't say that, because that would imply intellegence on the viruses part. But in a way....yes...viruses like Rabies do adapt things like that just to ensure that they find a new host. But its nothing to do with intellegence or any kind of higher function on a viruses part. Its just something that a virus does to ensure its spread. Like how the flu collects in the mucus, sneezing results in flu viral particals taking to the air. Thus spreading the virus. Just in their nature I suppose
Maybe the virus is merely giving an infected corpse the ability to reanimate itself so that it can walk around in order to spread the disease. But I really don't think that the virus is controlling the corpse, kinda like the flu, it doesn't control us but merely rides along inside of us.
Thats a point I was trying to make there, it just sounds wrong since it would imply the virus is intellegent. It doesn't " control" the corpse per say. Merely imprints a command, changing the behaviour pattern in a similar manner to rabies.
Seems more life natural selection to me. Thats what I have observed. The weak merely get eaten and don't re-animate because I assume not much is left to re-animate. The ones that get infected but survive become zombies. The flesh eating is probably a by-product of the virus, much like what others have theorized. I may be a pro-ghoul human, but even I can draw a scientific analysis.