The other thread here wondering what if some women ceased being pregnant made me wonder something else. What if a third of each nation perished, what would be the immediate and long term results of that? apologies for poor grammar.
Cemeteries would overfill rather quickly. Or probably run out of Kingsford charcoal for at while.
Or Conagra starts making Soylent Green!!!
If you’re one of the three, you have no worries.
Look up the after effects of the Black Death in Europe, that will give you a starting point.
HOW 1/3 dies will also have an effect - what happens after a plague is different than, say, a meteor impact that takes out 1/3.
It’s unlikely to be truly random, as lots & lots of money can buy you out of lots & lots of consequences.
Are we talking all at once, in a single moment? That’s just a slightly less severe version of “The Snap”, from the Avengers movies. The after effects would end up killing far more people, over the next few minutes, days, and months: You’d probably end up with somewhere between 1 and 10% of the population surviving.
Any plausible “real-world” scenario, the deaths aren’t going to be randomly distributed, and they’re going to be over a span of time. Both of those make a big difference. If a city were to get nuked, for instance, most of the people who would be hit hardest by the after-effects would be the same people who were killed initially. And if a deadly plague spreads over the course of a year, we’ll have a year to adapt to the new situation.
I feel like I’ve seen this scenario before (1/3 dead, distributed evenly).
Initially, there’s shock, to people’s feelings, and to the economy (not enough workers to keep stuff moving). Then things adjust to the new normal. Then there might be a population boom, as the infrastructure is there, and more resources than before.
The boom worked out fine during and after the Black Death, when the world was simpler and the niches to be filled were mostly in agriculture and low skill jobs, if I may oversimplify slightly. But today, with our complex economies and mutual dependency due to complex interconexions the results would be catastrophic, I am afraid. Look at what is happening with a couple of percent points of people missing in a couple of sectors with the omicron surge. If the knowledge and the people to man the electricity and the water networks, the nuclear power plants and the food distribution, warehouses and Amazon and much more disappeared I cannot imagine how a boom would work out. I see an economy nose diving and tail spinning simultaneously.
Ooh, can we pick the demographics of the one third?
I’m thinking of The Hitchhiker’s Guide to the Galaxy, where they come across a planet where 1/3 has been left after the two other thirds rocketed off to another planet.
(Sorry, been a long time, but…)
As I remember it, that there were three groups: A was the class of “movers and shakers of society”; C was the working class, who actually did the labor; and the B group were in between: the middle-managers of the world.
The B group just couldn’t understand why the A and C groups hadn’t told them where they were going, and. hadn’t come back for them.
Yeah, well, we’ve recently seen how well humanity doesn’t adapt to a new disease…
Just googling… first hit:
As you doubtlessly remember, somewhere in the Hitchhiker’s Guide series Mr. Adams told the story of the The Golgafrinchans, a race of people who sent their Telephone Sanitizer population away. The Sanitizers were sent along with another third of the planet’s population who were also deemed useless to form a colony on a remote planet (Earth as it happens). Of course, the remaining Golgafrinchan population was then wiped out by a virulent disease contracted via unsanitary telephones.
Yeah, the lacking telephone sanitizers will doom us.
I do believe that they were the looked down classes, like telephone sanitizers.
They were abandoned, but then the other 2/3rds died off from a plague spread by dirty telephones.
ETA: Ninja’d
When a third of humanity dies you will only be ninja’d 66% as often as you are now - until they all die out too and nobody will ninja you anymore. 
Thanks, folks. I hadn’t even thought about that since I first read the book (so, forty-plus years). I’m not surprised I got things wrong, sorry!
Though I kind of like my version… funny how my brain forgot some parts and added others!
Didn’t the black plague kill about 1/3 of people? Civilization still survived, but people were traumatized by it.
Immediate effects would be a lack of respect for institutions that failed them. Religion and government. Long term effects, probably a labor shortage. Basically what we’re going through now with covid but much more intense.
Global warming would be solved.
2/3 of the human population, per the lastest estimates of just under 8 billion, would be approximately 5.2 billion, enough to continue environmental disruptions.
Thanos would be 67% satisfied.
Postponed?