In any battle, understanding your enemy can be a powerful tool and this scenario is no exception. A ‘zombie’ is simply a reanimated corpse – a human who has physically died and returned to a ‘living’ state with limited functions. They have no pulse and their brain capacity is essentially non-existent. Their ability to recall any memories of their pre-infected life is a current topic of debate, but what is universally accepted is the idea that zombies are merely ‘eating machines’ that continue to operate for one sole purpose – to consume non-infected flesh (they do not prey on each other). Their sheer determination and persistence to satisfy this need against all odds is one of their more frightening characteristics. There is also a commonly held belief that zombies only seek to devour human brains, but this is not accurate – they are by no means picky eaters. Their main advantages over humans include the fact that they do not register fear or pain – they can take on a substantial amount of physical damage and, barring a sharp blow to the head, will continue in their pursuit. They can often be recognised by their peculiar stride, unsightly gaping wounds, absent limbs and their blank, emotionless facial expressions. However, the most well-known trait is that of the unsettling moan uttered from the zombie in its attempt to communicate.
As for the ‘lifespan’ (if it can so be called) of such a creature, one could speculate that it would be relatively similar to that of an uninfected individual – when left to its own devices; a zombie would continue to walk the earth until it literally withers away (i.e. crumbles under its own weight, leaving the brain matter to completely disintegrate) – this process could take any number of years. However, the time taken for any remaining cellular activity to disappear entirely depends on a number of factors including environment. For example, in hot/humid climates, the rate of decay would rise rapidly and consequently shorten the activity of the undead. On the other hand, colder environments may provide conservation or indeed leave the subject in a permanent/frozen state of living death (be cautious of thawed out corpses in such situations).
Two main types of such creatures have been depicted – the slow, shuffling zombies, as portrayed in Romero’s work, and the more recent concept of the faster, more aggressive zombie (examples of which can be found in the Dawn of the Dead remake, 28 Days Later and Zombieland). Dealing with either type has its advantages and drawbacks, and although sprinting zombies are obviously more of a threat, slow zombies can be equally lethal in multitudes.