J. Respiration
The lungs of the undead continue to function in that they draw air into and expel it from the body. This function accounts for a zombie’s signature moan. What the lungs and body chemistry fail to accomplish, however, is to extract oxygen and remove carbon dioxide. Given that Solanum obviates the need for both of these functions, the entire human respiratory system is obsolete in the body of a ghoul. This explains how the living dead can “walk underwater” or survive in environments lethal to humans. Their brains, as noted earlier, are oxygen-independent.
K. Circulation
It would be inaccurate to say that zombies have no heart. It wouldnot be inaccurate, however, to say that they find no use for it. The circulatory system of the undead is little more than a network of useless tubes filled with congealed blood. The same applies to the lymphatic system as well as all other bodily fluids. Although this mutation would appear to give the undead one more advantage over humanity, it has actually proved to be a godsend. The lack of fluid mass prevents easy transmission of the virus. Were this not true, hand-to-hand combat would be nearly impossible, as the defending human would almost certainly be splattered with blood and/or other fluids.
L. Reproduction
Zombies are sterile creatures. Their sexual organs are necrotic and impotent. Attempts have been made to fertilize zombie eggs with human sperm and vice versa. None has been successful. The undead have also shown no signs of sexual desire, either for their own species or for the living. Until research can prove otherwise, humanity’s greatest fear—the dead reproducing the dead—is a comforting impossibility.
M. Strength
Ghouls possess the same brute force as the living. What power can be exerted depends greatly on the individual zombie. What muscle mass a person has in life would be all he possesses in death. Unlike a living body, adrenal glands have not been known to function in the dead, denying zombies the temporary burst of power we humans enjoy. The one solid advantage the living dead do possess is amazing stamina. Imagine working out, or any other act of physical exertion. Chances are that pain and exhaustion will dictate your limits. These factors do not apply to the dead. They will continue an act, with the same dynamic energy, until the muscles supporting it literally disintegrate. While this makes for progressively weaker ghouls, it allows for an all-powerful first attack. Many barricades that would have exhausted three or even four physically fit humans have fallen to a single determined zombie.
N. Speed
The “walking” dead tend to move at a slouch or limp. Even without injuries or advanced decomposition, their lack of coordination makes for an unsteady stride. Speed is mainly determined by leg length. Taller ghouls have longer strides than their shorter counterparts. Zombies appear to be incapable of running. The fastest have been observed to move at a rate of barely one step per 1.5 seconds. Again, as with strength, the dead’s advantage over the living is their tirelessness. Humans who believe they have outrun their undead pursuers might do well to remember the story of the tortoise and the hare, adding, of course, that in this instance the hare stands a good chance of being eaten alive.
O. Agility
The average living human possesses a dexterity level 90 percent greater than the strongest ghoul. Some of this comes from the general stiffness of necrotic muscle tissue (hence their awkward stride). The rest is due to their primitive brain functions. Zombies have little hand-eye coordination, one of their greatest weaknesses. No one has ever observed a zombie jumping, either from one spot to another or simply up and down. Balancing on a narrow surface is similarly beyond their ability. Swimming is also a skill reserved for the living. The theory has been put forth that, if an undead corpse were to be bloated enough to rise to the surface, it could present a floating hazard. This is rare, however, as the slow rate of decomposition would not allow by-product gas to accumulate. Zombies who walk or fall into bodies of water will more likely find themselves wandering aimlessly across the bottom until eventually dissolving. They can be successful climbers, but only in certain circumstances. If zombies perceive prey above them, for example, in the second story of a house, they will always attempt to climb to it. Zombies will try to scale any surface no matter how unfeasable or even impossible. In all but the easiest situations, these attempts have met with failure. Even in the case of ladders, when simple hand-over-hand coordination is required, only one in four zombies will succeed.
2. Behavioral Patterns
A. Intelligence
It has been proven, time and again, that our greatest advantage over the undead is our ability to think. The mental capacity of the average zombie ranks somewhere beneath that of an insect. On no occasion have they shown any ability to reason or employ logic. Attempting to accomplish a task, failing, then by trial and error discovering a new solution, is a skill shared by many members of the animal kingdom but lost on the walking dead. Zombies have repeatedly failed laboratory intelligence tests set at the level of rodents. One field case showed a human standing at one end of a collapsed bridge with several dozen zombies on the other side. One by one, the walking dead tumbled over the edge in a futile attempt to reach him. At no time did any of them realize what was happening and change their tactics in any way. Contrary to myth and speculation, zombies have never been observed using tools of any kind. Even picking up a rock to use as a weapon is beyond their grasp. This simple task would prove the basic thought process involved in realizing that the rock is a more efficient weapon than the naked hand. Ironically, the age of artificial intelligence has enabled us to identify more easily with the mind of the zombie than that of our more “primitive” ancestors. With rare exceptions, even the most advanced computers do not have the ability to think on their own. They do what they are programmed to do, nothing more. Imagine a computer programmed to execute one function. This function cannot be paused, modified, or erased. No new data can be stored. No new commands can be installed. This computer will perform that one function, over and over, until its power source eventually shuts down. This is the zombie brain. An instinct-driven, unitask machine that is impervious to tampering and can only be destroyed.
B. Emotions
Feelings of any kind are not known to the walking dead. Every form of psychological warfare, from attempts at enraging the undead to provoking pity have all met with disaster. Joy, sadness, confidence, anxiety, love, hatred, fear—all of these feelings and thousands more that make up the human “heart” are as useless to the living dead as the organ of the same name. Who knows if this is humanity’s greatest weakness or strength? The debate continues, and probably will forever.
C. Memories
A modern conceit is that a zombie retains the knowledge of its former life. We hear stories of the dead returning to their places of residence or work, operating familiar machinery, or even showing acts of mercy to loved ones. In truth, not a shred of proof exists to support this wishful thinking. Zombies could not possibly retain memories of their former lives in either the conscious or subconscious mind, because neither exist! A ghoul will not be distracted by the family pet, living relatives, familiar surroundings, etc. No matter who a person was in his former life, that person is gone, replaced by a mindless automaton with no instinct other than for feeding. This begs the question: Why do zombies prefer urban areas to the countryside? First, the undead do not prefer cities, but simply remain where they are reanimated. Second, the main reason zombies tend to stay in cities instead of fanning out into the countryside is because an urban zone holds the highest concentration of prey.