Skeptophilia (skep-to-fil-i-a) (n.) - the love of logical thought, skepticism, and thinking critically. Being an exploration of the applications of skeptical thinking to the world at large, with periodic excursions into linguistics, music, politics, cryptozoology, and why people keep seeing the face of Jesus on grilled cheese sandwiches.

Tuesday, August 30, 2011

Modeling the zombie apocalypse

I usually tell you a little about my topic before I give you my solemn promise that I didn't make any of it up.

This one is so weird that I'm going to put the disclaimer first:

I swear I'm not making any of this up.

A team of medical researchers from two universities in Ottawa have released a paper (published in the Journal of Infectious Disease Modelling Research Progress) containing a mathematical model of what would happen to a population during a zombie attack.

The team was comprised of Philip Munz, Ioan Hudea, Joe Imad, and Robert J. Smith?.  And no, I'm not being tentative, there, with that last name.  The question mark is part of Dr. Smith?'s name.  I wonder how it's pronounced, don't you?   Do you have to say it like a question?  At parties, do people go up to him and say, "Hello there, Dr... Smith?"

Myself, I wouldn't have thought it was legal to have a punctuation mark as part of your name.  But now that I find that apparently it is, I think I'll follow suit.  From now on, my name will be Gordon Bonnet!  That way, people will always seem excited to see me.

In any case, the aforementioned medical research team seems to take the whole zombie-study thing awfully seriously.  Here's the actual abstract of the paper:
Zombies are a popular figure in pop culture/entertainment and they are usually portrayed as being brought about through an outbreak or epidemic. Consequently, we model a zombie attack, using biological assumptions based on popular zombie movies. We introduce a basic model for zombie infection, determine equilibria and their stability, and illustrate the outcome with numerical solutions. We then refine the model to introduce a latent period of zombification, whereby humans are infected, but not infectious, before becoming undead. We then modify the model to include the effects of possible quarantine or a cure. Finally, we examine the impact of regular, impulsive reductions in the number of zombies and derive conditions under which eradication can occur. We show that only quick, aggressive attacks can stave off the doomsday scenario: the collapse of society as zombies overtake us all.
I also have to quote the first line of the paper itself, just because it's so memorable: "A zombie is a reanimated human corpse that feeds on living human flesh [1]."  The coolest thing about this is that they sourced this information.  The source, if you're curious, is The Zombie Survival Guide - Complete Protection from the Living Dead, by Max Brooks (2003, Three Rivers Press, pp. 2-23).

The article then goes on through some amazingly abstruse mathematics to show that a zombie outbreak would be "catastrophic" and could be "disastrous, unless extremely aggressive tactics are employed against the undead."

Have I mentioned that I am not making any of this up?

In the conclusion of the article, Munz, Hudea, Imad, and Smith? state:
In summary, a zombie outbreak is likely to lead to the collapse of civilisation, unless it is dealt with quickly. While aggressive quarantine may contain the epidemic, or a cure may lead to coexistence of humans and zombies, the most effective way to contain the rise of the undead is to hit hard and hit often.
What I find most amazing about all of this is that there was no attempt to tie this to any real, actual epidemic; the whole article was about zombies.  Doesn't that strike you as a little weird?  Now personally, I  love it when scientists take something whimsical and use it as a model for a real phenomenon; one of my all-time favorite studies was when a team of evolutionary biologists used "mutations" (i.e. typos and changes in wording) in chain letters as an analogy to random alterations in DNA, and used it to model how cladistic taxonomy works.  It was sheer brilliance.

This, though... well, I'm not sure I see the relevance.  I can't think of any disease that works anything like, um, zombification, so all of the mathematical twiddling about doesn't really have any apparent application.  Not, of course, that I object to scientists having a little fun once in a while -- but this made it into a peer-reviewed journal, and presumably was the result of a grant from a funding agency of some sort.  Dr. Neil Ferguson, who is one of the UK's top governmental medical advisers, seemed a little uncomfortable when asked about the study.  "My understanding of zombie biology is that if you manage to decapitate a zombie, then it's dead forever," he said, in an interview, and went on to state that other than that characteristic, "zombification" didn't really seem to parallel any known disease particularly well.  "[No infectious illness known] actually causes large-scale death or disease, but certainly there are some fungal infections which are difficult to eradicate."

Smith?, however, was undaunted, and told a BBC reporter, "When you try to model an unfamiliar disease, you try to find out what's happening, try to approximate it.  You then refine it, go back and try again."  Even, apparently, when said unfamiliar disease doesn't, technically, exist.

So, there you have it, then.  A mathematical model for the zombie apocalypse.

Oh, and by the way, if you still don't believe me, here's a link to a BBC article about the study.  In the lower right hand part of the page there's a link that says "Zombies Study (University of Ottawa)" that will allow you to download a free pdf of the entire paper.

Reading all of this stuff leaves me feeling kind of dazed, incapable of doing anything but stumbling around the house with a blank expression, making moaning noises.  Of course, that may be because I'm still waiting for the coffee to finish brewing.  No need to show up at my door with axes.  Honestly.


  1. Congratulations on joining the ranks of the punctuated, along with psychic Wendy!. I'm considering adding a punctuation symbol to my name, but ! and ? seem so final. Perhaps a semicolon or ellipsis.

  2. do an interrobang (?!) its the best of both world.