What do you think is the biggest threat to humanity?

[anoni]

Everybody knows of all the doomsday scenarios that fly around. Mass human extinction to pandemics, global warming, nuclear war, nanotechnology, artificial intelligence, astronomical impacts, agricultural disasters, economical disasters and so forth all can lead to the end of the world. What do you think is the most likely or most feared doomsday scenario?

[Alphaart]

the most probable is the one where everybody decide to do nothing and ohe ozone end up all **censor** up and we die because of the extreme climate

[WingedZephyr]

In my opinion, our biggest problem across the world is overpopulation. Although there is still a lot of land on Earth that is more or less unpopulated, just because the space exists for us to stand in doesn't mean that it's healthy for our species to cover every inch of it. As we expand, other plants and animals go extinct, we use up vital resources that don't get replenished, pollute the environment, and throw the ecosystem completely off balance. As long as we have a world population that wants to reproduce to their hearts' content while trying to keep everyone alive as long as possible, it is inevitable that there will be a point when the world simply can't support all of us any longer. The possible side effects of that would be for wars to break out, people starving, governments to collapse, the environment to die, and basically for everyone to start fighting over the limited basic needs of survival that are left. It's potentially the cause of pretty much any or all of those things you listed in the first post.

One way or another, I think we're kind of just going to doom ourselves. If we're lucky, maybe a small portion of our species can survive and start over again with a better approach.

Though there's always a chance that something natural, sudden, and unexpected will wipe us out... but we're such an adaptable species that it's difficult to imagine natural events succeeding in killing all of us. Possible, certainly, but less likely than us causing our own eventual destruction.



Good job choosing a cheery topic, Anoni.

[NovaAurora]

    There are two different categories I think about for this subject. One is the end of "humanity as we know it," that is civilization, government, economy, and resource utilization being radically reduced or altered. The second is quite simply extinction. Now, I think that the latter is a lot less likely in any foreseeable future, and could only be brought on by some unknown extraterrestrial factor like an asteroid, or a cataclysmic natural disaster like the eruption of of a supervolcano that would change the chemistry of the atmosphere and biosphere for centuries. Even a microscopic catalyst, such as some kind of uber-plague, I don't think would be enough to cause outright extinction. It would be too easy to quarantine humanity underground or something, and who knows if we might evolve a natural defense for it eventually anyway.


    The first one however, I don't just think is likely but I believe is definitely going to happen, possibly within the next hundred years or so. The first major contributor will be climate change. We're already to the point where significant environmental changes are doomed to happen due to rising temperatures by the end of the century, and it can only get worse from here. Agriculture, fish stocks, and countless species whose effects and production we rely on will be severely affected. There will be widespread famine in poorer areas of the world, unprecedented heat waves, devastating storms, and other catastrophes that would require massive amounts of funding to repair.


    Simultaneously, in part due to to rising temperatures but also to the pollution and over exploitation of non-replenishable watersheds, we'll be facing a water crisis. Crops will be unable to grow, further impacting food production. Large cities and urban areas that depend on such supplies will be crippled as public services cease to be able to perform their functions. All this will naturally lead to degradation of society, possibly spurring protests, riots, and politically motivated acts of violence that will of course take any sort of media precedence over the actual underlying issues at hand. As the worldwide economy begins its epic collapse, there will undoubtedly be fighting over the remnants of Earth's remaining resources. Fossil fuels, water, land, whatever people can be killed over, they will be killed over. I wouldn't be surprised at all if this was the first true large scale nuclear war, especially if countries in places like the middle east have the capabilities to engage in such a thing.


    The combination of the altered climate, possible nuclear fallout, financial crisis, inevitable warfare, and political instability will compound together to create the end of "humanity as we know it." Many people who aren't killed by lack of food, water, or effects of natural disasters will die in the hostilities or succumb to diseases brought on by absence of medical treatment (not to mention how our immune systems will be weaker than ever at that point because of over vaccination and living in unhealthily sterile living spaces.) It will never be enough to outright kill everyone, but it will be enough to ensure that humans as a species can't fully recover for an extremely long time.

[ST-84 Sahelanthropus]

I'm glad to see that Zombie apocalypses aren't being mentioned.

My answer is the overthrowing of all governments, forming total anarchy. When civilisation crumbles down to pure chaos and daily life has degenerated into little more than unending survival and paranoia, we all might as well be dead.

[✡]

Either a virus or overpopulation. People don't realize how easy it is for something like a biological weapon or a communicable deadly disease to spread despite containment efforts. It's actually a wonder that something like Ebola hasn't already made it to America (if you don't count Ebola Reston/Marburg which proved to be only communicable with primates).

[Marcus]

Biggest threat to humanity? Stupid humans.

[Friday]

Either a virus or overpopulation. People don't realize how easy it is for something like a biological weapon or a communicable deadly disease to spread despite containment efforts. It's actually a wonder that something like Ebola hasn't already made it to America (if you don't count Ebola Reston/Marburg which proved to be only communicable with primates).

Not really... the CDC is remarkably efficient with quarantine methods. Ebola could never become a widespread epidemic because there's no host animal in the US; in the areas it's native to, it can "hide" in all sorts of primates. But since there aren't any native primates in the US, it would only travel with people, who could only infect others by very difficult means.

Now, that doesn't mean something else couldn't pop up, but it would have to be basically made to spread through containment efforts AND be highly lethal, an unlikely combination. There's a reason everyone's not dead from many of the highly lethal diseases in the world, and it has to do with sanitation and good public health policy.

[anoni]

So I'm going to throw in my two cents for each issue!

@Alph: Ozone layer being depleted is an interesting one. It is very true that if the Ozone layer were depleted then there would be less protection from UV radiation. We could have people getting sunburnt much easier, which sounds a bit trivial but when you realize it'd probably increase the rate of cancer to a considerable level, the situation becomes more serious. There are other effects of course of depleting the ozone layer but less protection from the suns radiation is what generally gets us. Did you know if the earth had no magnetic field, we would have no protection against solar winds, effectively killing all life on earth?

@Zeph and Nova (seeing as you've said similar things): What you say is quite interesting, and what a lot of experts come down to. I liked Zeph's idea because it encompasses Nova's idea as well in a way, overpopulation (and I suppose technological advance) leads to all sorts of problems such as climate change and all the other stuff you both have mentioned. There was a convention designed for people who specifically looked for existential crisis to discuss them, and most of these "experts" voted that humanity has a 19% chance of becoming extinct this century, the validity of that statement can't be known. I think really, the best way to tackle both of your extinction scenarios (which I'm sure you were aware of) is whether we can find ways to solve those issues fast enough. Planet colonization, artificial teraforming or a life-style change may all be things that could solve the issue, though whether we can do those things in time is still the question. I agree though that generally that will become one of the largest threats to humanity, over-population and climate change. Also props for the long answers and analysation! All of it was fun to read xD

@Betrayal: I find this a really interesting one! All governments overthrown due to some reason and anarchy to ensure. I wonder if in such a scenario a society would naturally form from the chaos, seeing as we as humans are social animals, we have evolved to seek a society and an authority. My personal belief is that anarchy is MORE unstable than society, in the sense that you are more likely to get a society from anarchy than you are anarchy from a society. But it's a really interesting point and I like it!

@Kanga: Another interesting one! A biological threat could definitely be the end of humanity as we know it, and indeed may very well be the end of all humans with total and utter extinction. The problem with the virus idea is that a virus that kills people can't spread, so a virus that can make humanity extinct can't actively spread very easily. I think one of the best ways for a virus to become a serious threat is for it to be extremely deadly to humans, but it spreads actively through a different medium in which it doesn't effect. Like say, a virus in flies that doesn't harm the fly, but if you go near a fly you get infected with the virus and it kills you quickly. Even then, due to human resistance, vaccines, protocols and even just remote tribes of humans that exist in the middle of nowhere, full extinction would be difficult.

@Flarei: While I disagree with the fact that humans are stupid, seeing as they are the smartest thing we know, I can however agree that humans will probably be the cause of human extinction. This runs along Zephs and Nova's idea as well, also it encompasses the chance of nuclear war. Interesting fact, if India and Pakistan, who hate each other, were to engage in nuclear war, the resulting dust cloud could be enough to plunge the earth into a nuclear winter, which could be severe enough to wipe out humanity as we know it.

@Friday: I agree with a lot of things you just said. But another reason we're not all dead is because generally viruses don't really want to kill us, I mean obviously they don't have "wants" but they evolve to survive. They evolve to get as much virus as possible, and killing the host isn't a good way to get more viruses. Generally the viruses that kill humans aren't human viruses, they are animal viruses that transfer to humans, they aren't designed to spread in humans and because of this they may have a chance to be effective killers of humans. So human sanitation and what not have something to do with it, but even before we did that viruses still couldn't kill us, and I think the primary reason for that is, well, a virus that kills people isn't a successful virus.

[Marcus]

"While I disagree with the fact that humans are stupid, seeing as they are the smartest thing we know..."

Allow me to re-phrase what I meant, "Ignorant humans." All man is what we describe as smart. Some more than others, some less. The main threat is a consensus of ignorance. Ignorance of a fact, of a threat, of possibility and et cetra.

I would like to stress that these next parts consist of estimation, guesstimation, and theoretical possibilities.

And while nuclear war, in all accounts, is devastating, it would most likely not kill ALL humans. It would certainly hinder.. "Progress" with the human civilization, but nuclear exchange would most likely be limited, thanks to missile defense, mutually assured destruction, and the general thought that nuclear bombs hurt everyone. It also depends on what nuclear weapons hit where. An average missile of the DPRK can (in theory) hit anywhere in Japan. If it where to penetrate the defense systems the U.S. has in place in that region, and hit Tokyo, it would be devastating. BUT, their technological level in nuclear weapons is just above the bar of a dirty bomb. If my remembering is correct, they have somewhere between 6 and 9 kilotons of TNT in their latest nuclear test. In comparison, the bomb dropped on Hiroshima in WWII was 16kt of TNT. This, though tragic, would not cause as significant damage of the Little Boy. Not to mention the Japanese use concrete now instead of wood, and reinforce all multistory buildings for earthquakes. Bad? Very. But not threatening to global ecosystem or population, as the U.S. and all other retaliating forces would most likely not escalate the situation by responding with nuclear devices. But on to my next example.

Say the U.S., Russia and China all decided they hated each other (more so than usual) today. Russia, China and the U.S. begin full-scale nuclear exchange. Russian missiles, though historically flimsy (I have not seen any indication of upgraded delivery devices, though I am sure they exist), have quantity (an estimated 10,000), and powerful thermonuclear warheads that have the largest power range, up to 50mt (Though it is strongly suspected none above 30 have been manufactured, or are mountable on missiles). China has an estimated 240 nuclear weapons with high delivery quality, but slightly lower yield (Averaging somewhere between 660kt to 4mt). The U.S. has an estimated 10,000 missiles of high quality. These, however, have a moderate yield possibly peaking around 30, but having clusters of devices for any purpose.

If a nuclear exchange between these powers began, few would survive on the surface longer than 2-3 minutes after detonation in those nations population centers, and the centers of their allies. Smaller nations, such as Israel and Iran may take hits, and if possible, could respond with their own NBC weapons. That would lead to poisonous gasses, plant death, radiation, hyper pollution, sun blocking, ect. But humans could possibly survive. Some, not all, but just some. That would give hope that eventually they, if they survived, could re-inhabit the less radioactive damaged areas. This is because the majority of radiation after a nuclear blast of 10mt decays after two weeks. The next step is three months, in which surface living would be possible with respiratory devices. After 200-500 years, the vast majority of all radiation would be gone, and any nuclear winter would be fading or gone. This would lead to a "Nuclear Spring" where any plant life that may have survived, or could be replanted could possibly grow, and do well. After a specific amount of time, I'll give it 100 years for the lols, things would go downhill quickly. The blasting of the ozone, loss aerosols from the nuclear detonation and the settling of the 'dust', so to speak, would leave a slightly-much thinner ozone layer. This would lead to more water in the atmosphere, which could lead to more greenhouse gasses being secreted, which could lead to runaway climate change, turning us into Venus.

However, if the nuclear summer is short, does not occur, or is moderate, it can lead to an eventual restoration (I'm using that word EXTREMELY liberally) of the climate, which over time would lead to a restored biosphere.

But I am slightly off topic. My point being, human civilization /could/ live on after nuclear war. Not well or very happily, but it is possible.

[Friday]

The estimates I have read (source: National Geographic: http://news.nationalgeographic.com/news/2011/02/110223-nuclear-war-winter-global-warming-environment-science-climate-change/) state that a devastating nuclear winter is possible even with a very few (under 30) nuclear bombs going off, a winter that would kill most of humanity through starvation. Most nations, I believe, know this, and therefore don't really want to kill themselves with their enemies. Hence, nuclear war is probably not that big a threat to humanity. There's no way for anyone to blow up another nation without killing themselves, too.

[maggintons]

Mankind is the threat to humanity


the pro wrestler called mankind knew this

[MrRazot]

Technological advancement with a hunger for power.

[Arquette]

Hard to guess, but it seems the consensus points to overpopulation. I would add that it brings not only social unrest because of too many people living too close together, but also a mass risk to a virus or even TB that alarmingly is on the increase.  Our world is potentially threatened by despots such as the trigger-happy, west-bating Kim Jong-un, who was voted as the 'Sexiest Man Alive' by The Oinion in 2012  But humour aside, I honestly have no idea.

[Maine]

I don't think It's one event that will expel mankind from the land, rather the two intrinsic values of man kind, that will in one way or another equate to disasterous events; our need to constantly progress and not look back.

Imagine if you will, a worldly bus seated by all of mankind, on they travel aiming for the perfect destination.
Low and behold! In the distance approaches a side street labeled Goal Rd, but the bus passes by anyway without inspecting.
"Did you not see the sign?" asks a passenger, "Is that not where we are headed?"

"It is indeed where we are headed," says the driver, "But i'm sure we'll find a way there if we keep on our current path."

It's a floored logic, but we abide by it, and I find it rather poetic that our striving is what will kill us all in the end.