Thursday, 3 November 2011
Greetings from a conference in Romania! Unfortunately, the conference was not on vampires this time. We, scientists, have to meet and talk about mundane problems from time to time. Besides, Romania can be a normal country too!
What we would like to tell you today is the story of Dracula. Dracula, as we know him, was the center figure of Bram Stoker’s 1897 eponymous novel. According to the book, he lived in a castle in Borgo pass, so today thousands of tourists go to castle Bran near Brasov, Romania to breathe in the terrifying atmosphere and (perhaps) to see the Count with their own eyes. In fact, the castle has nothing to do with the novel (or with Count Dracula) and is only being marketed by Romanian tourist agencies to gullible tourists. You can read an interesting and funny encounter of a search for Dracula described by Tanya Gold from The Guardian here.
However, do not try to ask your Romanian friends about “Dracula”! Dracula is a fictional figure and after several minutes of discussions you will settle the dispute in by talking about Vlad III, Prince of Wallachia (1431-1476) who was known as “Dracula” (meaning “son of the Dragon”). Vlad’s father was a member of the Order of the Dragon (Dracul) which gave him this nickname. Vlad was a cruel and gruesome ruler but he managed to fight the Ottoman Turks well and was praised by both his people and by his allies. He became known for impaling his enemies, a habit that also earned him the nickname “Vlad the Impaler” (“Vlad Ţepeş” in Romanian).
Allegedly, Bram Stoker stumbled upon Vlad while studying Romanian and Hungarian history and used the name for his main character (the initial idea was “Count Wampyr”). In reality, however, Vlad III does not have anything to do with vampires. On the contrary, he is a respected historical figure and a national hero. In 1997 Romania printed stamps with his portrait and in 2010 National Bank of Romania minted commemorative coins dedicated to Vlad on the occasion of celebrating 550 years since the first mention in writing of Bucharest, under his rule, on 20 September 1459.
Bram Stoker was rather basing his plot on so-called “vampire craze’' that took place in the 1720s and 1730s in a part of Serbia that was temporarily attached to the Habsburg monarchy after the Treaty of Passarowitz (1718). Two peasants, Petar Blagojevic and Arnaut Pavle, who died suddenly and without any obvious reason and were reported being seen after their deaths, allegedly caused several other mysterious deaths of their fellow villagers in the settlements of Kisiljevo and Medveda. The Austrian authorities were called in and the whole affair culminated in an exhumation of suspected vampires, cutting off and burning of their heads and bodies. The whole story which was most likely caused by the poor understanding of infectious diseases and knowledge of the decomposition of human body, was vividly described in official reports of that time and attracted Stoker’s attention while his research in the British Library.
Let us analyze the events described in “Dracula” (and Stephen King’s “’Salem’s Lot”, which provides a very similar scenario but is set in New England). The interactions between vampires and humans are portrayed in the following way: a vampire selects a human victim and gets into its proximity (it typically happens after dark and the vampire needs the victim to invite her/him in). Often the vampire does not require permission to enter the victim’s premises and attacks the sleeping victim. The vampire bites the victim and drinks the victim’s blood, then returns to feed for 4-5 consecutive days, whereupon the victim dies, is buried and rises to become another vampire (unless a wooden stake is put through its heart). Vampires usually need to feed every day, so more and more human beings are constantly turned into vampires.
Assume the events described in “Dracula” (or in “’Salem’s Lot”) were real. How would things evolve given the Stoker-King model dynamics described in both sources? Let us take 1897 as the starting point (i.e. the year Stoker’s novel was first published). In 1897, the world population was about 1 650 million people.
The initial conditions of the Stoker-King model are the following: 1 vampire, 1 650 million people, there are no organized groups of vampire slayers (Jonathan Harker and Abraham van Helsing could not be, by all means, considered very efficient vampire slayers). In order to solve this, the Cauchy problem is applied. Due to the fact that the total sum of humans and vampires does not change in time (human population does not grow and humans gradually become vampires), we get to the predator-prey model which is diminished to a simple problem of an epidemic outbreak
The solution to this problem is the following: the human population is drastically reduced by 80% by the 165th day from the moment when the first vampire arrives. This actually means on the 165th day of Count Dracula’s arrival to England the human population reached its critical value and practically became extinct (following the definitions of “Critically Endangered species” by the International Union for Conservation of Nature). At that precise moment, the world would have been inhabited by 1 384 million vampires and 266 million people.
Let us observe the speed with which vampire population grows. The growth of vampire population is extreme: at first, the number of vampires jumps up abruptly, but then slows down and declines. We can determine the moment of time when the speed of vampire population’s growth reaches its maximal values. It is the 153rd day and the number of vampires is the highest (825 million vampires and 286 million of newly turned vampires).
The increase in one population (vampires) inevitably leads to the decrease in another (humans). When the number of vampires reaches the number of human population, the humans disappear altogether. The presence of vampires in the Stoker–King model brings the mankind to the brink of extinction. Therefore, we have to conclude that the Stoker-King model describes the “explosive” growth of vampire population. Within the two months of Dracula’s arrival to England (or Kurt Barlow’s arrival to New England), there would have been 4 thousand vampires in operation. The model analyzed in this scenario is very similar to an epidemic outbreak caused by a deadly virus (e.g. Ebola or SARS). According to the Stoker-King model, vampires need just half a year to take up man’s place in nature. Therefore, the co-existence of humans and vampires described by Bram Stoker seems highly unrealistic.
Sorry everyone! Dracula just does not work! Fortunately, there are other interesting things that do work. Follow our blog and learn more about supernatural economics!