# What kind of post-apocalyptic scenarios would result in 100% destruction of the human race? **URL:** \ **Category:** Factual Questions\ **Created:** [October 12, 2012, 3:42pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526 "2012-10-12T15:42:44Z")\ **Posts on this page:** 20\ **Page:** 2
**Author:** ![Michael63129](https://avatars.discourse-cdn.com/v4/letter/m/3da27b/32.png) [@Michael63129](https://boards.straightdope.com/u/Michael63129)\ **Post date:** [October 12, 2012, 7:13pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/21 "2012-10-12T19:13:17Z")
> [@Szlater](#): > > Nearby gamma-ray burst could do it, if I remember Phil Plait’s book right. Only the side facing the burst would be sterilized though, with the other side only having to worry about the UV radiation after half of the ozone layer is destroyed (this is usually mentioned as the most significant effect, [many articles](http://news.bbc.co.uk/2/hi/science/nature/4433963.stm) don’t say anything at all about sterilization from the GRB itself), thus, humans would probably be able to survive, if with a drastic decline in population, especially if it hit the Asian side, and having to avoid all sun exposure. We could also still grow food in greenhouses since glass blocks UV (which would also help against the ice age that may follow). ---
**Author:** ![Jonathan\_Chance](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/jonathan_chance/32/701_2.png) [@Jonathan\_Chance](https://boards.straightdope.com/u/Jonathan_Chance)\ **Post date:** [October 12, 2012, 7:37pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/22 "2012-10-12T19:37:19Z")
> [@snowthx](#): > > Tangent. That would make an interesting SciFi novel or movie. What would humanity do if it knew it was the last generation? Would we still go about our jobs, wars, and save money for the future? What would happen to the economy, medicine, research, religion? There would be a “last person born”, and eventually, a “last person alive”. Presumably, the rest of nature would persist as humans decline, so the world would be intact. I wonder what people and society would do if it was known that there was no future beyond our own lifespans. There’s also an exploration of such here > **[The Songs of Distant Earth](https://en.wikipedia.org/wiki/Songs_of_Distant_Earth)** > > The Songs of Distant Earth is a 1986 science fiction novel by British writer Arthur C. Clarke, based upon his 1958 short story of the same title. Of all of his novels, Clarke stated that this was his favourite. Prior to the publishing of the novel, Clarke also wrote a short step outline with the same title, published in Omni magazine and anthologised in The Sentinel in 1983. > The story is set in the 39th century and depicts the journey of the spaceship Magellan as it carries a large group of c... It takes place on a world where they know Earth is going to end. But they don’t care too much. ---
**Author:** ![snowthx](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/snowthx/32/10660_2.png) [@snowthx](https://boards.straightdope.com/u/snowthx)\ **Post date:** [October 12, 2012, 7:55pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/23 "2012-10-12T19:55:36Z")
> [@solosam](#): > > [Children of Men - Wikipedia](http://en.wikipedia.org/wiki/Children_of_Men) Thanks! I will check it out. ---
**Author:** ![beowulff](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/beowulff/32/542_2.png) [@beowulff](https://boards.straightdope.com/u/beowulff)\ **Post date:** [October 12, 2012, 8:07pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/24 "2012-10-12T20:07:13Z")
> [@Jonathan\_Chance](#): > > There’s also an exploration of such here > > [The Songs of Distant Earth - Wikipedia](http://en.wikipedia.org/wiki/Songs_of_Distant_Earth) > > It takes place on a world where they know Earth is going to end. But they don’t care too much. I grabbed this book out of the hands of [this](http://farm4.static.flickr.com/3341/3652997747_0e66bfbb59.jpg) guy (it was a Bookcrossing book). I’d be happy to send it to whoever wants it. ---
**Author:** ![temp\_user](https://avatars.discourse-cdn.com/v4/letter/t/9de053/32.png) [@temp\_user](https://boards.straightdope.com/u/temp_user)\ **Post date:** [October 12, 2012, 8:23pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/25 "2012-10-12T20:23:02Z")
Something like Kurt Vonnegut’s ice-nine? [Cat's Cradle - Wikipedia](http://en.wikipedia.org/wiki/Ice_nine) ---
**Author:** ![Lasciel](https://avatars.discourse-cdn.com/v4/letter/l/e79b87/32.png) [@Lasciel](https://boards.straightdope.com/u/Lasciel)\ **Post date:** [October 12, 2012, 8:57pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/26 "2012-10-12T20:57:20Z")
> [@Chastain86](#): > > Indeed. I’m interested in scenarios in which humankind has died out in total, but the planet itself continues to spin. This would eliminate any scenario in which the Earth was entirely consumed by fire, crushed by a massive meteor, etc. I dunno, even an asteroid has to be pretty damn massive to prevent the Earth from spinning. We didn’t even stop when we got punched and the moon formed, if I’m remembering my science classes correctly. If all you want is for the planet to remain, and to be presumably somewhat hospitable to other sorts of life eventually, then we could get smacked by some pretty big crap that could very likely cause a human-extinction event. Short of that, I’m with everyone else that a designed pathogen or virus would have to be created to do the trick - otherwise, we’re just awfully stubborn and tenacious. Even a massive volcano eruption isn’t going to kill off the species - it’ll kill off a damn many of us, but all we need is around 2500 or so reasonably varied specimens in contact with each other to keep the population limping along into the future. Maybe not a very noble or spectacular future, but still not extinct either. ---
**Author:** ![dracoi](https://avatars.discourse-cdn.com/v4/letter/d/90db22/32.png) [@dracoi](https://boards.straightdope.com/u/dracoi)\ **Post date:** [October 12, 2012, 9:14pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/27 "2012-10-12T21:14:49Z")
Looking at history, I see two possibilities: If climatic conditions permitted a snowball Earth to re-form, I could see that being the end of the human race, especially if it happened quickly at our current tech level. But if you gave us even another 100 years, I think we’d have time and capability to adapt to living under the ice and growing food in green houses. (Then the question is whether we blow ourselves up fighting over who gets to be saved and who freezes.) Another historical possibility is the Siberian traps. That killed 90% of species the first time around, and I think it’s significant that the activity lasted 1 million years and took tens of millions to return to “normal.” We might be able to survive under adverse circumstances for a while, but I wonder if we could tolerate a million of years of that kind of stress. In the science fiction realm: Some sort of massively aggressive nanomachine might do the trick. A virus can only infect a certain range of species, but you could imagine a nanomachine capable of digesting any carbon-based material (or, at least, anything composed of amino acids). This would allow it to spread even to isolated tribes of people and to destroy even the building blocks of the food chain. Survivors would have to try living in enclosed bubble communities, and we’re a long way off from having the technology to do that. ---
**Author:** ![Senegoid](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/senegoid/32/6606_2.png) [@Senegoid](https://boards.straightdope.com/u/Senegoid)\ **Post date:** [October 13, 2012, 4:29am UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/28 "2012-10-13T04:29:39Z")
> [@temp\_user](#): > > Something like Kurt Vonnegut’s ice-nine? [Ice-nine - Wikipedia](http://en.wikipedia.org/wiki/Ice_nine) I was thinking of that too. In the late 1960’s and early 1970’s there was a fear going around that some scientists somewhere (the Russians had it first, of course) had actually produced something like this. Called [Polywater](http://en.wikipedia.org/wiki/Polywater), it was a form of water that was viscous and somewhat syrupy at “normal” temperatures, and could supposedly cause regular water to become polywater on contact. When the ice-nine went feral in _Cat’s Cradle_, it strangely seems to have wiped out all life except for a small group of isolated humans on the very Caribbean island where the disaster happened. One might suppose there were other isolated pockets of human life left too. But there was no apparent way those people could have survived for very long (they’d have run out of food before too long). (And that Caribbean population had only one female, not of breeding age.) So if somebody does invent something like ice-nine, and it gets loose, that would do it. (How hypothetical a disaster does the OP contemplate?) ---
**Author:** ![drewtwo99](https://avatars.discourse-cdn.com/v4/letter/d/d07c76/32.png) [@drewtwo99](https://boards.straightdope.com/u/drewtwo99)\ **Post date:** [October 13, 2012, 6:04am UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/29 "2012-10-13T06:04:05Z")
I think the OP has already ruled out large-scale impact, but [something like this](http://www.youtube.com/watch?v=LlF8APEkh-E)would definitely wipe out all human life on Earth. Very fascinating to watch. Also, if you’re interested, there is a great (but very old and never updated) website called [Exit Mundi](http://www.exitmundi.nl/exitmundi.htm)that goes through a laundry list of every conceivable and implausible way humanity could cease to exist. It’s well written and lots of fun, but VERY poorly designed. Ugh. ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [October 13, 2012, 7:41am UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/30 "2012-10-13T07:41:52Z")
A “one-two punch” would have a good chance of doing so; first something like a nuclear war or plague massively reduces our numbers, then something else like a supervolcano or asteroid impact kills off the survivors. A nearby pass by a massive object like a planet or star could throw the Earth into a non-survivable orbit, or out of the Solar system entirely. A runaway greenhouse effect could turn Earth into another hothouse like Venus; however such a thing is unlikely at this point in the planet’s history, apparently. A galactic jet such as from the “[Death Star Galaxy](http://www.space.com/4753-galaxy-blasts-neighbor-deadly-jet.html)” could destroy all surface life. > [@Chastain86](#): > > Aside from our sun going supernova,\* \\* Nitpick: Our Sun isn’t the kind of star that goes supernova; it’s too small. ---
**Author:** ![Bosda\_Di\_Chi\_of\_Tricor](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/bosda_di_chi_of_tricor/32/16845_2.png) [@Bosda\_Di\_Chi\_of\_Tricor](https://boards.straightdope.com/u/Bosda_Di_Chi_of_Tricor)\ **Post date:** [October 13, 2012, 10:52am UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/31 "2012-10-13T10:52:10Z")
Hit or near-miss with a large solar flare. ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [October 13, 2012, 11:04am UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/32 "2012-10-13T11:04:16Z")
> [@gnoitall](#): > > A persistent (dormant in the environment until it can infect) pathogen which inflicts 100% sterilization on its victim would do the trick. The youngest generation infected would be the last generation of humanity except we’d have 90 years of so to figure out a way to overcome the sterilization with technology (they can immediately start training all the youngest people in fertility biotech to give us the most time). I find it hard to believe we couldn’t figure out a way to keep reproducing with 90 years and unlimited resources to throw at the research. ---
**Author:** ![Ruby\_Slippers](https://avatars.discourse-cdn.com/v4/letter/r/94ad74/32.png) [@Ruby\_Slippers](https://boards.straightdope.com/u/Ruby_Slippers)\ **Post date:** [October 13, 2012, 11:20am UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/33 "2012-10-13T11:20:12Z")
> [@coremelt](#): > > except we’d have 90 years of so to figure out a way to overcome the sterilization with technology (they can immediately start training all the youngest people in fertility biotech to give us the most time). I find it hard to believe we couldn’t figure out a way to keep reproducing with 90 years and unlimited resources to throw at the research. We wouldn’t have 90 years – more like 40. We would only have the number of years until the youngest females could no longer be impregnated and bear children. Even with IVF technologies, it’s hard to imagine we’d have more than 60 years. And if we finally succeeded at 60 years, there wouldn’t be many left to raise those children. ---
**Author:** ![coremelt](https://avatars.discourse-cdn.com/v4/letter/c/4491bb/32.png) [@coremelt](https://boards.straightdope.com/u/coremelt)\ **Post date:** [October 13, 2012, 11:34am UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/34 "2012-10-13T11:34:55Z")
> [@Ruby\_Slippers](#): > > We wouldn’t have 90 years – more like 40. We would only have the number of years until the youngest females could no longer be impregnated and bear children.. Frozen sperm, frozen eggs, artificial womb and you’ve got more time. We’d have 40 years with unlimited resources to develop the artificial wombs. Anyway it’s hard to imagine that in 20 years we couldn’t undo whatever havoc this pathogen has done to our reproductive systems. Also, you can imagine a society developing where they keep a few uninfected reproductive individuals in some kind of sterile biosphere and then send out “drones” who get infected to do all the hard work and provide for the reproductive minority and they only have contact through completely sterile portals. Males would only need to be kept in the biosphere long enough to reach puberty and freeze a bunch of sperm, then they get kicked out into the contaminated environment to become worker drones. This would give you unlimited time to find a tech solution to reverse the problem. Anyway I can’t imagine this scenario wiping the human race out, we’re just too resourceful. ---
**Author:** ![ekedolphin](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ekedolphin/32/10003_2.png) [@ekedolphin](https://boards.straightdope.com/u/ekedolphin)\ **Post date:** [October 13, 2012, 11:56am UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/35 "2012-10-13T11:56:26Z")
Took me awhile to find an article that I first read years ago, but [here](http://www.ldolphin.org/twentyways.html) are 20 ways. **Natural Disasters** 1. Asteroid impact 2. Gamma-ray burst 3. Collapse of the vacuum 4. Rogue black holes 5. Giant solar flares 6. Reversal of the earth’s magnetic field 7. Flood-basalt volcanism 8. Global epidemics **Human-Triggered Disasters** 1. Global warming 2. Ecosystem collapse 3. Biotech disaster 4. Particle accelerator mishap 5. Nanotechnology disaster 6. Environmental toxins **Willful Self-Destruction** 1. Global war 2. Robots take over 3. Mass insanity **A Greater Force is Directed Against Us** 1. Alien invasion 2. Divine intervention 3. Someone wakes up and realizes it was all a dream Me personally, I’ll put half my money on 17, 25% on 19 and 25% on 20. 😃 ---
**Author:** ![ExTank](https://avatars.discourse-cdn.com/v4/letter/e/35a633/32.png) [@ExTank](https://boards.straightdope.com/u/ExTank)\ **Post date:** [October 13, 2012, 2:23pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/36 "2012-10-13T14:23:09Z")
> [@MikeS](#): > > If you eliminate the “leave the Earth intact” requirement, you could always go for a [false vacuum scenario.](http://en.wikipedia.org/wiki/False_vacuum) That would wipe out all life on Earth, and probably the Earth itself along with a good chunk of the cosmos. It’d do it right quick, too; by definition, we’d never see it coming. This sounds suspiciously like Spontaneous Existence Failure. ---
**Author:** ![Ethilrist](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ethilrist/32/4604_2.png) [@Ethilrist](https://boards.straightdope.com/u/Ethilrist)\ **Post date:** [October 13, 2012, 4:06pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/37 "2012-10-13T16:06:51Z")
Really pissed-off OCD aliens. ---
**Author:** ![Don\_t\_Panic](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/don_t_panic/32/398_2.png) [@Don\_t\_Panic](https://boards.straightdope.com/u/Don_t_Panic)\ **Post date:** [October 13, 2012, 7:59pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/38 "2012-10-13T19:59:44Z")
> [@Shmendrik](#): > > That’s got to be the least comprehensible Wikipedia article I’ve ever seen. You obviously haven’t read the one on [deconstruction](http://en.wikipedia.org/wiki/Deconstruction). ---
**Author:** ![Der\_Trihs](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/der_trihs/32/233_2.png) [@Der\_Trihs](https://boards.straightdope.com/u/Der_Trihs)\ **Post date:** [October 13, 2012, 8:15pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/39 "2012-10-13T20:15:38Z")
> [@ExTank](#): > > This sounds suspiciously like Spontaneous Existence Failure. Not the same thing at all. SEF is a massive simultaneous quantum event that’s incredibly unlikely to happen even if it’s possible at all. A collapse to a false vacuum if it’s possible simply requires the proper local conditions to be achieved for it to happen. It’s like supercooled water suddenly freezing if you shake the bottle or drop in some powder; it’s a metastable state collapsing into a more stable one. A false vacuum collapse though violates the “leave the planet itself relatively intact” clause in the OP; it wouldn’t even leave atoms or (most?) subatomic particles behind. The universe as we know it would be destroyed. ---
**Author:** ![Ethilrist](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/ethilrist/32/4604_2.png) [@Ethilrist](https://boards.straightdope.com/u/Ethilrist)\ **Post date:** [October 13, 2012, 8:24pm UTC](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526/40 "2012-10-13T20:24:25Z")
> [@Der\_Trihs](#): > > A false vacuum collapse though violates the “leave the planet itself relatively intact” clause in the OP; it wouldn’t even leave atoms or (most?) subatomic particles behind. The universe as we know it would be destroyed. “I don’t tink I much give a \*\*\*\* what dey do after dey destroy the universe, Paulie…” – Fast Eddie Costigan [Previous page](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526.md?page=1) [Next page](https://boards.straightdope.com/t/what-kind-of-post-apocalyptic-scenarios-would-result-in-100-destruction-of-the-human-race/637526.md?page=3)