Sunday, November 22, 2009

Why Vampires don't work (2)

My frivolous little post the other day on how vampires cover their expenses was but a prelude to this, what I think is the major implausibility about vampires.
Let us ignore the biology geek's objection about whether such a large and vigorous creature can sustain itself on blood alone (and, if it can, on what quantity of blood??).  I am prepared to accept that the vampire's diet is just 'magic': it doesn't necessarily get nutrition from blood in the same way that mortal creatures do; this is just a part of the way it is, a compulsion that it has to follow.
But vampires do drink blood.  From human mortals.  To the point of killing them.  Quite often.
How often, exactly?  Well, in some tales, like Dracula, the vampire can spread out his feasting on a single victim over several days, or even weeks.  In others, it is suggested that some vampires try to limit their murder rate by feeding on animals... or by stealing human blood from hospital blood banks.  But, in general, it looks as though they're killing someone at least once a month, possibly once a week; in some cases, considerably more often than that.
Now, even if a vampire takes great care in concealing the bodies of his victims, and preys only upon the lonely and destitute, people on the margins of society who are less likely to be reported missing.... well, even so, that rate of killing is probably going to become noticeable before long.  Even in quite a large city.  In a smaller community, the impact is going to be immediate.
In recent Swedish vampire film Let The Right One In there's a (highly unusual) murder, another attempted murder, a disappearance, and a (highly unusual) assault, all within the space of a few weeks, or perhaps just days, in one small town - in fact, all within the environs of a single housing estate - and the local people pretty soon realise they've got a serial killer on their hands (the world of this film seems to be one in which people don't know about vampires).
It can't really be any other way.  Vampires have a very distinctive and conspicuous way of killing people.  They don't usually take much care about concealing their victims' bodies.  And they surpass the headcount of any regular serial killer in quite a short space of time.
It's not just the attention this would attract that bothers me.  It's the demographic impact: even one vampire could exterminate a small community over the course of a few years. 
And usually we have multilple vampires.  Indeed, we conventionally have a situation where the victims of a vampire become vampires in turn.  Some writers have realised that if this were invariably to happen, there would be an exponential growth in the number of vampires - and vampires would eventually completely replace the mortal human population (what would they eat then?); so, they've tried to find ways of limiting the conversion of victims into new vampires - usually a suggestion that it is somehow the vampire's choice whether a victim becomes undead or simply dies.  Even so, most vampire stories do seem to have quite a high rate of conversions - vampires want company, vampires want sex, vampires want an entourage, vampires like the feeling of power involved in creating new members of their kind.
So, you have more and more vampires feeding on humans.  Where is it going to end?
Well, if any normal laws of nature were in play, I suggest it would have ended in the extinction of both species long ago.  Sorry, horror fans - vampirism is a potent symbol, but it's just not remotely plausible as a basis for a story.


Unknown said...

I think it's pretty strange that there are people who actually believe vampires exist. We definitely would have noticed by now. Do the Chinese believe in such things (other than by contamination by movies from the West)?

Let's not forget that the whole modern tradition of vampire stories got started with a novel that drew its themes from a whole bunch of Victorian worries and obsessions that had nothing to do with the paranormal. Dracula, Frankenstein and Jekyll and Hyde were all symbolic stories that have somehow acted so powerfully on the public's imagination that they've attained legendary status, and left us with story themes that somehow just won't go away. A fascinating mass psychology phenomenon! Perhaps there really is a need for a Harvard professor of symbology a la Dan Brown.

Froog said...

Yes, the Chinese have vampires, and I think it's quite an old folkloric tradition. The notion of the vampire does seem to be very ancient and very widespread around the world, even though it only achieved pop culture prominence in the modern world through Bram Stoker.

In Chinese it's xi xue gui - literally "blood-suck ghost". They have the deathly paleness and (I think) the inability to go out during the day. They also have a quirky form of locomotion (at least in Hong Kong horror films!): they HOP everywhere. This is ludicrously unscary, and means that they can be easily kept at bay by high fences, etc.

Froog said...

If I might add a comparison that outraged horror fans may more easily grasp - the ecology (or epidemiology) of vampires is essentially the same as that of zombies. Given their voracious appetite and their ability to spread their 'infection' to others, they're soon going to overrun the planet. In most modern zombie films, it is recognised that, basically, the whole world goes zombie in the space of a few months after the first outbreak. The spread of vampirism might be much slower, but it would tend towards the same end over the course of several centuries.

Kevin said...

A recent SF book I read (I forget the title, but it's by Peter Watts) links the predator:prey ratio issue to vampires' long periods of dormancy. If the number of humans is getting too low to sustain the vampire population, they just spend a couple of centuries dead in their coffin and wake up when food stocks have replenished themselves.

Froog said...

Well, full marks for effort to Mr Watts. Taking time off from whittling down the human population might avoid or at least defer the extinction of the human race, but it doesn't solve the other two related problems with vampirism: i) the impossibility of vampire activity being 'inconspicuous'; ii) the tendency of vampires to proliferate.

The Nag said...

Why can't vampires farm their victims i.e. drink blood from them and keep them alive (in some dungeon somewhere) so that they can drink blood from again?

This is what the Masai do with their cattle since they drink blood from them.

JES said...

The original novel I Am Legend on which the recent(ish) Will Smith film was based tackled head-on a lot of the paradoxes in the vampire mythos. (In Richard whatzisname's book, the creatures were vampires -- in the recent film, they were more 28 Days-maddened-zombie-ish.)

You might be interested in a quasi-academic treatment of the problem, using the setting and premises of Buffy the Vampire Slayer as a test case. For instance:

Let’s assume the following:
* Sunnydale’s human population growth rate is 10% annually, which is at the high end for a budding California community.
* A vampire feeds every three days, and encounters about one hundred potential victims in the course of a day, meaning that 1 out of every 300 encounters involves a little refreshment.
* An individual vampire sires a victim every other year, or once per 240 feedings.
& Buffy and her Slayerettes, busy little beavers that they are, annually stake about 1/3 of the vampires plaguing Sunnydale.
* Vampires are flocking to Sunnydale, since the Hellmouth is the underworldly equivalent of Silicon Valley, and the demon labor market is just too good to be true. Thus, we’ll assume a yearly migration rate of about 10%, or the same as for the humans.

The result of which is that Sunnyvale, California, has an "equilibrium vampire population" of about 18, and an "equilibrium human population" of about 36,000.

The paper's author concludes:

Although the creators and writers of "Buffy the Vampire Slayer" are probably not theoretical ecologists, and although we are consistently amazed by the depth and sophistication of their fabricated milieu's continuity, it is downright nifty that the show appears to make ecological sense.

The whole thing is here (among other places, I suspect).

JES said...

P.S. Contrast the Buffy paper with this one, which works it out differently -- assuming a starting vampire population of 1, and human population of 536,870,911 (the global human population on 1/1/1600, an arbitrary start date for "the first vampire"). This gives the human population 30 months to drop to 0.

Froog said...

Ah, science! Thank you, JES.

Although I do sometimes fret that the resources of the Internet are doing a disservice to the fine arts of uninformed speculation and pontification.

I was never a huge Buffy fan, but it seems to me that the vampire population of Sunnydale was often considerably more than 18, and that Buffy was usually killing scads of them each week.

Froog said...

By the way, Nags, I tried to reply to you last night, but the comment got eaten.

I merely said, "I didn't know that about the Masai. Yick!"

Froog said...

Of course, the 'immortality/extreme longevity of vampires is another factor that makes conventional demographic projections a tad tricky.

It's an interesting thought that vampires need vampire-killers to maintain a viable level of population; they need to be culled.

However, I think even the most prolific vampire-killers have a much lower strike rate than the vampires; in most of these stories there are are many human victims (and, often, conversions into vampires) for every vampire slain. That's not good for the long-term trend.

JES said...

It just occurred to me that maybe the conversion-into-vampires rate is really not as high as one might think -- because it depends on the victim's and the vampire's genetic compatibility. Maybe that kills off many more victims than are converted.

(Vampires themselves, of course, would not be as vulnerable to mismatches. I imagine their digestive tracts are something like those of vultures and other scavengers: nigh-immune to things which would kill anyone else.)

Gothika Z said...

If you look at traditional or older vampire stories, the way of converting a human to a vampire is to drain them completely of 'life blood', and then make them drink the blood of the vampire. This would mean a vampire could bite whoever they liked, as long as they didn't kill them, they would go unnoticed.
If you go by more modern stories where conversion happens when a victim is bitten, then you'd probably notice most of the vampires that prey on humans are travellers, so do not create serial murders.
Most fictional vampire writers try to introduce a factor that overcomes this problem - as a final example there are vampires who only need blood occasionally, and actually get nutrition from human food.

Froog said...

I think you have to drink the vampire's blood before you've been completely drained of your own - otherwise you'd be dead, and not in a position to drink anything.

'Travelling' doesn't make you any less of a serial killer, it just makes your killings a little less easy to link to one another. In a small community - such as we had in Let The Right One In - even two or three murders, even one is pretty damned conspicuous. And I have never read or seen a vampire story in which the vampires moved to another town after every feeding.

As far as I know, the idea of creating new vampires through letting victims drink the vampire's blood originates with Anne Rice. I don't think it exists in Dracula or any of the other 19th century vampire stories.

While a lot of modern stories seem to play with the difficulties of feeding - as I mentioned, allowing the drinking of animal blood or visits to the blood bank - I don't think I've ever come across one that really tackles this question of population dynamics: the fact that, if vampires are immortal and can propagate themselves freely, their numbers ought to rise rapidly over time. This, and the related problem of their impact on the human population (one active vampire exceeds the headcount of the worst serial killers; a whole bunch of them would have the impact of a civil war), are usually just ignored.