I am so very very tempted to post this news article without comment, aside from “GUYS GUYS THIS IS SO COOL” – which is actually exactly how I am in person and you’d never know I considered myself a serious science communicator in writing.Star Wars scientists use laser gun to kill mosquitoes in fight against malaria
Yes, that’s the actual headline the Telegraph
used, reporting on an article in the Wall Street Journal
reporting on work to develop a laser weapon that can shoot individual mosquitoes out of the air, homing in on the distinctive sound frequency produced by their wingbeats. 1980s Star Wars technology being used in the fight against disease. Excuse my Americanism: That’s awesome.
Well, unless you’re the kind of person who sees a story like this and immediately asks
What’s the point?
Can picking off one mosquito at a time really make a difference?
or an ecology minded person who wonders what kind of effect genus-level genocide would have on an ecology in which Anopheles
have been a factor for about 70 million years.
The Malaria Problem
Mosquitoes transmit malaria. Some mosquitoes are infected with the parasitic protest Plasmodium
, which when it infects humans, causes malaria. The WHO factsheet
on this disease says there were 247 million cases of malaria in 2006, and 880 thousand deaths, mostly in sub-Saharan Africa. I’m not going to bother detailing the economic impact of the epidemic, I think the humanitarian effort on its own is worth it.
There is currently no vaccine available for malaria; direct treatment of the disease is currently in the forms of curative and preventative drugs. And historically they’ve been very effective. Unfortunately, and as annoying as Jeff Goldblum was in Jurassic Park
Life will find a way
. Evolution happens. If you keep hitting a population with drugs designed to kill them, soon the entire population will be descended from those organisms that were resistant to drugs. New drugs work well for a few years, then resistance evolves. And that’s not even taking into account the very real problems with getting the drugs to the poverty-striken areas where they’re most needed, and the volume of counterfeit drugs on the market. Research proceeds into vaccinations, but in the meantime drugs are being supplemented by a method known as vector control. And that’s where mosquitoes come in.
The vector is the means of transmission of a disease, and in the case of malaria this is Plasmodium
-carrying mosquitoes. Vector control, therefore, involves trying to stem the population of mosquitoes. Fewer mosquitoes means fewer people will be infected, and a slowing down of the spread of the disease. The most effective method of this is widespread destruction of suitable mosquito habitat, but that has all sorts of impact on local ecology; it’s a bit like paving over your entire garden because one species of flower gives you hayfever. The past fifty years has seen insecticides such as rise as the main form of vector control, but aside from the major ecological impact that these chemicals have on the environment, we have the same pesky problem that we do with attacking Plasmodium
directly: organisms evolve; what doesn’t kill a population makes it stronger, and if a pesticide doesn’t irradicate a species in a few generations, it’s just another selection pressure in the environment for species to react to.
So research into other forms of mosquito control becomes a sexy topic – and there’s nothing grant providers like better than a sexy topic. Genetic manipulation of both mosquitoes and Plasmodium
are being developed, along with a variety of interesting or bizarre techniques such as sense disruption. The laser beam was developed using a grant by the Gates Foundation, and has been named the Weapon of Mosquito Destruction, which just goes to show that scientists as well as computer engineers have an incredibly dorky senses of humour.
I really do hate to be a killjoy sometimes, but deliberate extinction of any organism is not an endeavour to be taken lightly. Species interact with their environments in complex and sometimes subtle ways, and massive scale population reduction could have serious effects on other populations on the area, possibly even affecting agriculture and having a human impact.
Except – mosquitoes have no major predators relying on them for sustenance. No flowering plant is completely dependant on the nectar drinking males for pollination. They play a part in ecology, but they don’t appear to exclusively fill a niche upon which the ecosystem depends. I’m still not going to throw a party for mosquito extinction, and I wouldn’t say it’s a worthy aim, but they’re true pests, and this is one occasion when I don’t feel that bad about looking at a newly invented instrument of death, and say: damn, that’s cool.
It is cool; It’s a LASER BEAM that locates, targets and shoots down individual mosquitoes. There is nothing in that that isn’t cool.
And the very serious professional zoologists in my office have all agreed it has to look like an individual robot gun that spins on a dome-shaped turret, saying ‘target acquired’ in a little robot voice. Because what would be the point otherwise?