Scientists: Go ahead, kill all the mosquitoes.
blogs.chron.com
blogs.chron.com
We were well on our way to getting rid of mosquitoes, incidentally, until we banned DDT. Millions of dead humans are the very real consequence of that decision.
The idea that there exists a worldwide ban on DDT for vector control, and that out-of-control malaria and "millions of dead humans" were the "real consequence" is a complete fantasy. And a rather disgusting one, as well.
However, many mosquito species are becoming resistant to DDT, so it is not really useful any longer. For example, India has greatly reduced the use of DDT because most of its malaria bearing mosquitoes are resistant to it.
DDT kills mosqito predators too and the mosquito predators are usually bigger more complex creatures with longer lifespans so it is much harder for them to evolve a resistance to DDT. Thus the idea that you could wipe out mosquitoes with DDT is ridiculous. Mosquitoes just evolve resistances to it. However, you could wipe out many bird species with it.
Here is a good fact sheet on the issue:
http://www.ipen.org/ipenweb/documents/work%20documents/ddt_i...
Not that I want to endanger bald eagles either, but I'd be interested to see a less politically-charged, more pragmatic debate on the potential advantages and disadvantages of reinstating its use in limited capacities.
In the US the debate about DDT was whether to use it as a pesticide. So the choice was about killing the bald eagles and most of our other birds, or slightly increasing pest control costs for farmers and people with lawns.
Ecosystems are complex enough that we have very little information on all the interactions that could happen. It's more than just a bag of organisms mixed together. A better analogy is the network of files and components loaded up during the boot process. Especially early on, each piece is crucial to what happens next.
We have one weapon way more powerful than DDT. It is called intelligence and knowledge, things like controlling pools of water is way more effective that DDTing everything.
People with lack of intelligence or knowledge wants a magic pill that solves all problems without having to think, but this has an enormous cost. When I eat fish from Ebro Delta I'm eating DDTs thanks to them(they are forbidden but some people continue using them).
Yet people find easier to think of the problem from the other side and think that a bunch powerful people who bend the world to their own interests. It is true, there are those people, their effect is significant, but they are part of the game, they cannot control even themselves and their peers, not even when it would be in their interest (as a group).
Edit: And a different take on the 'No' conclusion from the original link. Turns out 'Yes, in these situations, though maybe not and does that matter?' is the more accurate analysis of 3500 responses.
Just wondering.
I get bad reaction to sandflies. If sandflies replaced mosquitoes, my world would be severely negatively impacted.
The point is, evolution has only one measure for success: continued existence. Everything else is irrelevant.
Say we kill all mosquitoes in the wild, and then discover that they were in fact protecting us from some Awful Thing. By the time we become aware of this, it may be too late to eliminate the problem by simply reintroducing caged mosquitoes to the wild, because some irreversible critical mass or adaptation may have happened in the meantime. (This is a Black Swan argument; it's a vaguely-defined scenario that seems very unlikely but potentially catastrophic.)
"The cost of these infections is immense, both economically and in terms of human suffering."
No doubt. But what we want is a cost-benefit analysis of removing mosquitoes from the ecosystem. Pointing to one large and obvious benefit does not help us calculate the costs.
I have described the immense harm caused by mosquitos. I have looked equally hard for mosquito benefits and found none that can't be provided by other species. To stand on the side of keeping mosquitos, you must find a benefit that outweighs trillions of dollars of lost economic output, millions of man-months of suffering, and several million deaths per year.
And the less likely your proposed benefit of mosquitos is, the better it must be to win in the expected value calculation.
"Views differ on what would happen if that biomass [of mosquitoes in the Arctic tundra] vanished. Bruce Harrison... estimates that the number of migratory birds that nest in the tundra could drop by more than 50% without mosquitoes to eat. Other researchers disagree...."
We're seeing disagreement on a hypothetical mosquito extinction's effect on the number of nesting birds in a certain area. If the experts are unsure of this, then it's fair to say that the total, detailed ecological impact is not precisely understood.
Also from the Nature article:
"Without mosquitoes, thousands of plant species would lose a group of pollinators. Yet McAllister says that their pollination isn't crucial for crops on which humans depend. 'If there was a benefit to having them around, we would have found a way to exploit them,' she says."
So if mosquitoes disappeared, thousands of plant species could be threatened. The researcher says that's probably okay, because if humans aren't directly using those plants, they're probably not important to us. But what about indirect benefits of those plants? Would the effects on those plant species have significant ripple effects on other species? I don't know. The Nature article doesn't talk about that.
Does this seem like the rigor necessary to justify a sudden ecological change in an extremely complex system on which billions of human lives depend? I don't think you can call this a sure thing.
As ab9 said, they could be outcompeting other pests that host far, far worse parasites. If mosquitoes were to disappear, these other pests would multiply to take over the niche and we would have something worse than malaria on our hands.
Of course, I'm not sure if there's anything like this. There certainly are other parasites, but I haven't heard of any where the hosts compete directly with mosquitoes. Then again, with something as huge as nature, there is always something waiting to be discovered. For example, we have been in contact with the host species for ebola for millions of years. Yet, ebola first appeared as late as 1976.
Something feels very wrong here. I can imagine a creature that promotes small amounts of blood sharing between different humans or creatures has positive as well as negative effects - and by definition we don't know what unknown benefits it has.
So let's kill malaria instead. How can we do that?
I'm well aware that malaria and other diseases carried by mosquitoes are a very large killer in parts of the world but why aren't we trying to cure these diseases rather than wipe out a whole species?
It just seems as if we, as a species, think we rule this planet so can do whatever we want with regard to the other species that exist on it.
Isn't collateral damage the entire problem with removing things from complex systems?
I seem to remember that back in the days of DDT, mosquitos were killed back to the point where malaria was no longer a big deal. Then the 70's happened, DDT went away, mosquitos and malaria came back big time, and farmers in Southeast Asia started dying in large numbers because the insecticides they used to replace DDT were actually harmful right now instead of 'probably carcinogenic over 20 years'.
Anybody know what the insecticide of choice is today, and whether it's as safe as (or safer than) DDT?
Life on earth doesn't stay still. Some will evolve, and some will go out extinct, and there will be a few mass extinction event there and there.
There are always consequences of everything- hell, it's one of Newton's laws. But it's entirely possible there are no terrible awful consequences.
But hell, who doesn't like a good a good genocide?