The Vampire Mosquito

I’ll admit some of the titles of the articles on this site may be slightly hyperbolic, and yet this title is probably one of the least exaggerated. Be afraid. Be very afraid. There exists a race of mutant  mosquito’s that never sleep and feed on human blood.

This very particular mosquito made its own home in the London Underground in the eighteenth century. The biologist Forskall was the first to distinguish them as a distinct and unique species, giving them the name Culex molestus. Culex essentially meaning mosquito (it is a very common form of mosquito) and you don’t require a knowledge of any Latin to have an idea what molestus means. They were, and remain to this day, very annoying.

The ‘standard’ mosquito naturally requires a warmer climate and it appears the London Underground provided an excellent breeding ground for these terrifying little critters. Well I say excellent… Nature has an amazing knack for providing life even in the darkest and most recess parts of our world. An underground train track appears to be no different.

So why is this particular species the ‘vampire’ species? They all suck blood.

The ‘standard’ mosquito, the Culex pipiens, of which we have come to know and loath, more often tend to ‘bite’ birds. They require a lot of space to mate and need blood to lay their eggs and have little mosquito babies. They also hibernate in winter, giving us some respite and generally are only at their height of blood-sucking during the warmer months.

Not the London Underground Mosquito.

This mosquito has adapted to living in small spaces, no longer requiring large spaces as they no longer search for large swarms to mate. They also no longer require blood to lay their eggs. Meaning there is no stopping to their screwing and baby-spewing ways. Also, they do not hibernate and remain active all year round. And finally (though I probably should have started with this) they appear to feed almost exclusively on the blood of rats and humans.

And now you see how they have more in common with Dracula than the common mosquito, of which they can no longer interbreed with as they have become so distinct from their now more distant cousins.

Their thirst for human blood appears to have been first brought to its highest during the Blitz. When thousands of Londoners took refuge in the underground system these mosquitoes saw opportunity and had a great feast it seemed. So there you go, the Blitz, not all bad.

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This is surely one of the most interesting and terrifying examples of the powerful force of natural selection and the amazing possibilities evolution provides. Whether the mosquito evolved entirely in the underground system, or in other small-space, dark environments, these amazing little things still came to be. Furthermore, they appear to be worldwide! It seems the creation of the molestus mosquito has occurred in many areas across the world. Any underground system, any basements, railways or just big holes, these vampire mosquitoes appear to have developed.

This example of speciation (the creation of a new, distinct species), occurred incredibly quickly. Perhaps it seems no surprise given the major forces involved. These environments provide a very powerful force to adapt, because if the didn’t they would very soon die out in these areas. This coupled with the large populations, rapid breeding speed and the provision of the necessary warmth and the removal of the seasons appears to have created the perfect conditions for these little guys to flourish.

It is both terrifying and incredibly exciting to see what nature makes next, particularly given we humans are creating a warmer, wetter, harsher world for these insects to live. What’s next?


P.S. These mosquito’s are still around just in case you were thinking of travelling to London, but don’t worry, they don’t seem to be much of a problem anymore.




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