Why vampires would have a population problem

See the rest on the blog.

clipped from www.newscientist.com Michael Marshall, reporter Maths blog Punk Rock Operations Research points out a major problem with the notion of vampires, which believers in our bloodsucking cousins would do well to note. Assuming vampires are effectively immortal, and that they can reproduce by turning normal humans into vampires, their population would explode. So in the imagined worlds in which they exist, what prevents them from over-running the planet? Colleagues in the New Scientist office suggest that there must be a high death rate caused by Slayers and other natural hazards, balancing out the high "birth" rate or mortals converted by bites. Such a mechanism could be modelled using the classic Lotka-Volterra equations for predator-prey populations. Although, of course, vampires are capable of making prey out of their supposed predators.

Does Vampire Exist?

I have read many books and manga about vampire, vampire story seems nice. But, does vampire (human vampire) really exist? I don't think so. I don't believe such things exist in this world. Here's the quote from skepdic.com:

This cultural link between vampirism and the quest for immortality seems to have been subordinated in literature and film, where other themes, such as blood for blood's sake, fear for fear's sake, or entrance into the realm of the occult, seem to dominate. One sign of the cultural deterioration of our ancestor's noble quest for immortality can be seen in the modern secondary meaning of 'vampire': a woman who exploits and ruins her lover. Another example of deterioration can be seen in the numerous WWW sites on vampires which appeal to occult or New Age interests such as entering the so-called dark side of reality, gaining power, establishing a unique identity as a special person or selling commercial products and games.

Apparently, role playing and masquerading as vampires is not enough to satisfy the bloodlust of some people, and covens or cults of "vampires" have emerged among some occultists. They seek blood to give them power, a sexual rush, or to establish a unique and special fictional persona based on creating fear and mystery in others. Unlike our ancient ancestors, their power is not sought because of fear based on ignorance and misunderstanding of nature, but on ignorance and misunderstanding of themselves. Like other occult cults these vampire covens are attractive to the young and the weak.* Just a few years ago, such "vampyres" would have been considered ill or evil. Today, they are said to have an "alternative lifestyle."