Aaah! Real Monsters: The Science Behind the Legends


In my last post, I took a quick tour through a few hundred years worth of vampire, werewolf and zombie folklore to see how the icons of horror fiction in legend differ from their modern interpretations (at least in one aspect: how an average Joe becomes one of the things that go bump in the night).*

As a follow-up, we're going to look at some of the real-world events and phenomena that may have inspired the creation of these monsters.


Rabies: Spanish neurologist Juan Gómez-Alonso watched a vampire movie one night after reading a study of viruses that infect the brain and was shocked by the similarities between vampirism and rabies. After studying vampire folklore and medical accounts of rabies infections, he published his findings in Neurology in 1998, proposing that vampire legends were inspired by rabies.

Gómez-Alonso's reading revealed that vampire stories became more common in Europe in the 18th century as different areas experienced rabies outbreaks, particularly in Hungary, where a rabies epidemic in dogs, wolves, other animals and humans tore through the country between 1721 and 1728.

Going down a list of characteristics associated with vampires, Gomez-Alonso noted that almost all of them could be explained as symptoms of rabies.

When the rabies virus begins to attack the central nervous system, it can cause insomnia, as well as agitation and dementia, which might cause the victim to become violent and attack people. Additionally, bright light, water, strong smells (garlic, anyone?) and mirrors can all trigger muscle spasm attacks during which victims cannot swallow and sometimes vomit blood. Sounds like a vampire to me.

Gómez-Alonso also hypothesized that the observation of animals and humans exhibiting these same symptoms gave rise to the idea that vampires could shape-shift.

And, or course, both rabies and vampirism can be spread by bites.

Porphyria: In 1985, Canadian biochemist David Dolphin proposed a link between porphyria, a rare blood disorder characterized by irregular production of heme (an iron-rich pigment found in blood), and vampire stories.

Dolphin found that two different types of this porphyria can cause symptoms that echo vampiric characteristics. Acute intermittent porphyria can cause neurological attacks like seizures, trances and hallucinations, which might last for days or weeks. People with porphyria cutanea tardea experience an extreme sensitivity to sunlight and suffer blisters and burns on sun-exposed skin. Porphyria is also hereditary, which could lead to concentrations of people suffering from it in certain areas.

Catalepsy: A cataleptic episode really doesn't draw many comparisons to vampirism, but it can put the thought of the walking undead into your mind. Catalepsy, a symptom of Parkinson's disease, epilepsy and other conditions and disorders affecting the central nervous system, causes rigidity of the muscles and slowing of the heart and respiration. Without advanced medical knowledge or diagnostic tools, a doctor could have pronounced someone in the middle of a days-long cataleptic episode to be dead. Not long after, the dearly departed might return from the grave after coming to in their casket and struggling to the surface.


Hypertrichosis: Congenital generalized hypertrichosis, sometimes called werewolf syndrome, is a hereditary condition that results in excessive hair growth on the upper body and face, including the nose, forehead and eyelids. The condition appears too rare, though "“ all 19 currently documented cases are in one Mexican family "“ to be the explanation for historic werewolf myths.

Rabies: In The Werewolf Delusion, Ian Woodward points to rabies as a likely cause for the inspiration of werewolf myths. As with the comparison to vampirism above, late-stage rabies and the dementia and aggression that come with it could cause people to believe a person suffering from the virus was becoming "bestial." If the person had contracted rabies from a wolf bite, people around them may have assumed that the wolf had passed some of its animal qualities along to them.

Aggressive animals: Wherever humans and animals live in close contact, there's a chance of conflict. Werewolves may have simply been a way to explain clusters of wolf attacks in small geographic areas, or even isolated incidents. People in places where there are no wolves may have done the same thing, given the existence of folklore featuring werebears in some parts of Europe, werehyenas in Africa, and were cats in various places (werelions and wereleopards in Africa, weretigers in India and werejaguars in South America).


Mental Illness: In a 1997 study, Roland Littlewood, a British anthropology and Chavannes Douyon, a Haitian physician, concluded that many of the zombies in Haiti may just be people suffering from psychiatric disorders or brain damage. The study, discusses the cases of three people who were thought to have been turned into zombies. They diagnosed the first person with catatonic schizophrenia, found the second to be suffering from brain damage and epilepsy caused by oxygen starvation of the brain and discovered the third had a severe learning disability caused by fetal-alcohol syndrome. They suggest that zombies may have become part of Haitian culture as a way to explain the condition of the mentally ill.

Zombies are (sort of) real: From 1982 to 1984, anthropologist Wade Davis traveled through Haiti to find the origin of zombie folklore. I should point out that the legitimacy of Davis's research, as well as his ethics and the literary merit of his books, have been questioned. Likewise, the research Davis's critics used to debunk also has its detractors. The whole controversy makes for interesting reading, but for now I'm simply summarizing Davis's work without comment.

During his research, Davis discovered that bokors use powders made from the dried and ground up pieces of various plants and animals in their rituals that can cause "zombification." Davis collected several samples of the bokors' zombie powder and discovered that they had some ingredients in common: charred and ground bones and other human remains, plants with urticating (barbed) hairs and puffer fish.

Davis hypothesized that, if applied topically, would cause irritation and the victim's scratching would break the skin. The tetrodotoxin found in the puffer fish, which the fish use as a natural defense, would then pass into the bloodstream, paralyzing the victim, slowing their vital signs and making them appear dead. The victim would be buried, and the bokor would dig the body up and force their "zombie" into labor. Davis also said that the bokors he met told him that when the victim is retrieved, they're fed a paste of sweet potatoes, cane syrup, and Datura "“ also called concombre zombie, the zombie cucumber "“ which contains the hallucinogens that cause delirium, confusion and amnesia.

Costas J. Efthimiou, a physicist at the University of Central Florida tackled various monster myths in his paper Cinema Fiction vs Physics Reality. In it, he describes the case of Wilfred Doricent, a teenager who became ill, died and was buried, only to reappear in his village over a year later. Efthimiou concluded that zombification is a real phenomenon, but void of the magic and sorcery found in folk tales:

The secrets of zombiefication are closely guarded by voodoo sorcerers. However, Fr`ere Dodo, a once highly feared voodoo sorcerer who is now an Evangelical preacher and firm denouncer of the voodoo faith, has revealed the process. It turns out that zombiefication is accomplished by slipping the victim a potion whose main ingredient is powder derived from the liver of a species of puffer fish native to Haitian waters. Well, we now have an explanation for how Wilfred could have been made to seem dead, even under the examination of a doctor. However, we have already said that the TTX paralysis was unlikely to have affected his brain. How does one account for Wilfred's comatose mental state? The answer is oxygen deprivation. Wilfred was buried in a coffin in which relatively little air could have been trapped. Wilfred's story probably goes something like this: Slowly, the air in Wilfred's coffin began to run out so that by the time he snapped out his TTX-induced paralysis, he had already suffered some degree of brain damage. At this point his survival instincts kicked in and he managed to dig himself out of his grave — graves tend to be dug shallow in Haiti. He probably wondered around for some time before ending up back the village. Neuropsychiatrist Dr. Roger Mallory, of the Haitian Medical Society, conducted a scan of zombiefied Wilfred's brain. Although the results were not as definite as had been hoped for, he and his colleagues found brain damage consistent with oxygen starvation. It would seem that zombiefication is nothing more then a skillful act of poisoning.

*For some, the tour may have been a little too quick. And exploring all the ways monsters in legend differ from modern fiction could easily fill a book. If anyone is looking for more monster folklore, or more info on the evolution of monsters from folklore to modern fiction, email me at flossymatt[at], and I can suggest some further reading.

If you've got a burning question that you'd like to see answered here, shoot me an email at flossymatt (at) Twitter users can also make nice with me and ask me questions there. Be sure to give me your name and location (and a link, if you want) so I can give you a little shout out.