If 1 million people were plucked from the Earth today and put on a new planet, how long would it take for a civilization to arise?

Question

The day on Earth begins as normal. People go to school, go to work, eat ice cream; nothing is amiss. Then, without warning, the sky seems to break open in a cacophony and flashing lights, and one-million unrelated people from around the globe find themselves falling upwards and into it. When they are able to orient themselves, the multitudes make two important discoveries:

1. They are currently treading water in the ocean about one hundred meters off-shore .

2. A ton of trash, loose objects, and furniture that could serve as aids to flotation seem to have accompanied them in the transition.

Unbeknownst to them, they have been instantaneously transported to another planet, perfectly earth-like (same/extremely similar flora/fauna, same size/gravity, same sun type, same moon type). There is absolutely zero chance of making contact with Earth, or returning (the planet is on the other side of the Milky Way, or in another galaxy altogether).

So here's the question: How long does it take them to get out of this dire strait, onto dry land, and to develop a new social order/civilization? I'm looking for estimates with good reasoning behind them, taking into account the number of people, their 21st century knowledge, whether whatever items they happened to have in their pockets could play a significant role, as well as whatever you think may be important. The climate that they've appeared in is Mediterranean.

The preferable unit for an answer would be generations, but feel free to give one in an actual time-unit as well if you think you can make a good case for it.

This has been getting some great answers! Here's an edit to clarify some points:

1. Detail on the population

   • Anyone in the world could be part of this group, therefore things like language and cultural barriers are as problematic as you'd expect.

2. More on the circumstances of departure

   • Everyone leaves at the same time. This means that some people are at a disadvantage, because it is night when they are taken.
   • However, assume that the transition is disruptive enough that if you are asleep, you WILL be rudely awakened, and have enough time to come to your senses before you're dumped into the water.

3. More on the circumstances of arrival

   • The area area of arrival is around 35 degrees north of the equator.
   • It is early summer on the planet.
   • The people arrive in the early morning (~ 30 minutes after dawn).
   • The people are distributed up and down the coast widely enough that on average each person has a bubble of personal space 10 feet in radius.
   • There is enough flotsam that people who cannot swim/poor swimmers have a reasonable chance to survive until rescue or until they are washed ashore.

4. The ocean

   • No strong swells or currents; there is a light breeze.

5. The land

   • Sandy beach gives way to sparse woodland/plains around 50 meters from the shore. It becomes mountainous around 20 miles inland.
   • There are ample sources of fresh water: streams, creeks, one or two major rivers. People won't have trouble finding water (though contamination may become a problem quickly?).
   • Otherwise, you can assume that the land is as accommodating to survival as any that naturally occurs on Earth.

6. The sky

   • Stars, planets are completely different from Earth's.
   • Moon is same size and brightness, but its surface has not been changed to resemble our own.

7. What I mean by "civilization"

   • I'm actually surprised that no one has called me out on this one yet. By civilization, I mean a centralized society that encompasses a large percentage of the descendants and has developed a unique language, culture, and identity.

Answer 1

First things first:

G - The Gathering

You say that

Anyone in the world could be part of this group, therefore things like language and cultural barriers are as problematic as you'd expect.

If this is true, then those people are gathered at different times - or they arrive at different times, or there is some way that they are gathered at different times but arrive at the same time.

If people are gathered at the same time, their state in Earth previous to G will be different: if Americans are caught at work, the Chinese will be caught at sleep, and conversely. This may significantly affect the prospects of survival. If you are caught at work, or transportation, while fully awake, it may be a lot confusing to find yourself in the water of a foreign world, but you are at least awake. Being transported while sleeping will add a lot more confusion and disorientation, and might give those people a lesser chance of surviving.

If they are gathered at the same moment of the day - ie, at 8 AM in the US and 8 AM in China, and so at different times - they would arrive at different times to the new world; if the Americans arrived in the morning, the Chinese would arrive at night. And this would again massively affect their survival prospectives, those who arrived during the day having way better chances to get to the shore than those that arrived at night.

And these differences in survival opportunities between the Chinese and the Americans would probably reflect in the cultural/linguistic environment of the surviving newcomers. Randomly, about 250,000 of them should be Chinese, but if the Chinese are caught at night or arrive at night, their numbers could be severely harmed, resulting in a less heterogeneous - and less representative - sample of newcomers-who-get out from the ocean.

So the logic solution is that everybody gets caught in the morning, not too early - say, about 9:00 AM - but by some magic/fluke of reality all of them arrive simultaneously. That is, G is spread along full 24 hours, but A - The Arrival - is within a single moment.

This unfortunately does not solve a similar problem regarding the year time. If Russians or Canadians are gathered in December, they will probably be too much dressed to swim properly, and will be at a disadvantage regarding people from the Southern Hemisphere or the Tropics. So perhaps everybody needs to be disrobed for the "trip", in order to preserve the proportion between Swahili speakers and Slavic languages speakers. Or G would have to happen all across the year, with people magically arriving at the same time.

After (I suppose; with this kinds of things one should not be too assured that the arrow of time doesn't misbehave, or that causality doesn't get messed) being caught, then people will be ready for

A - The Arrival

The time of arrival won't mess with the proportions of people of different cultures/languages/nationalities as much as G - but it will affect the prospects of everybody. Few people will get to the beach if A is at night, and if people arrive late in the afternoon, even if there is still light enough for everyone to see where the shore is, they won't be able to get a decent dinner before sleep, nor a breakfast the following dawn. Their chances would be maximised, in contrast, if A was relatively early in the morning, allowing them time to collect some fruit, hunt some birds, or fish something for lunch.

Similarly, I would say pretty much everybody would die if they arrive in Winter, or late Autumn, and perhaps even early Spring, and the place of arrival is too far from the Equator. So time and place of A should be taylored for this circumstance; either something like late May at 30 degrees North, or October at 30 degrees South, or under 20 degrees from the Equator either side.

Weather will be important, too - it is different to arrive at a whole new world in a sunny day with a mild breeze, or under heavy rain and strong winds. And these waters where they are arriving - are they free from sharks and other predators? Is it the high tide? Are there strong currents?

But all of this is easy. Big problem is, we are talking about one freaking million people, and people occupy space. They won't be able to swim, or do much besides drowning in their respective places, if they do not have a considerable space to move. In a very conservative estimate, at the very least some six square meters per person, a three meter long and two meter wide rectangle, so that they can move their arms and legs without hitting and kicking each others (and I fear this is still way too crowded for a happy outcome). This means the very bare area of six million square meters, which my school teacher told me equals six square kilometers! That is, if everybody is in between 100 and 200 meters from the shore - a tenth of kilometer wide band - they need to be spread through sixty kilometers, parallel to the coast. And better the coast ahead of them be relatively plane shores, not cliffs or rocky formations. So the place for A should be sixty kilometers long of calm waters, in front of nice beaches.

So, they come to the shore. That's

L - The Landing

Now everything went well, and the best part of a million people are at the beaches of an unknown continent - or is it an island? - of an unknown world. There is again a problem of space. They will again need some 100 meters between the sea line and mountains or jungle or other rough terrain, so that they can seat down, make some protective arrangement to avoid sunburns, and be able to even think about sleeping next night.

So L needs to be situated in relatively wide coastal plains, with not too dense jungle too close to the shore, but also not completely barren, for people will need shadows to protect themselves - palm trees, perhaps, with long and wide enough leaves that one can rest under them. And people will need fresh water - rivers, brooks, lakes - unless this new world has oceans of dessalinised water. Which will quickly change the geometry of the aglomeration of people - instead of a narrow band along the seacoast, narrow bands along the riversides. Which in turn demands more depth for the plains and lightly vegetated area towards the interior.

So the placement of L is quite complicated if you want to avoid high mortality on the first day.

Now that we have a million people landed into a new, unknown world, without the pressing need of disposing with too many thousands of dead co-catastrophers, the simple phase is over. It is time for complicated things, such as

B - The Breakfast

People will soon get hungry. And besides perhaps a few candy bars or cookies they might have in their pockets, or find among the debris, they have nothing to eat. So they will look for fruit. And here is the problem; you say that this is

another planet, perfectly earth-like (same/extremely similar flora/fauna, same size/gravity, same sun type, same moon type

And I am quite willing to believe you about gravity, sun, and moon (and atmosphere, and relief, and wheather, and whatnot), but fauna and (especially) flora will be different, barring some magical intervention from the gods who organised this event, because Earth's flora and fauna have been deeply modified by human activity. It would nice to find some bananas there, but they will probably be much smaller and less sweet than Earth's bananas, artificially selected and hybridated, during millenia, for size and flavour. And if they meet wolves or mooses, those won't be Earthan wolves or mooses, who know humans, and how much dangerous we are.

At this point, objets randomly transported from Earth may be important. Who wouldn't like to have a gun, or a steel knife, or a packet of matches (but those would be wet, and as such useless, unless they can dry them, perhaps?) in such a situation? Those things will be the more precious as they will not be renewable in the foreseeable future; once the matches have been used, fire will be only possible through more primitive methods. Luckily someone will have a magnifier, and be willing to use it to light bonfires for everyone. All hail our leader, the magnifier owner.

But let's admit that people find enough fruit - or edible mollusks and insects (though probable it will take some days starving for them to overcome their prejudices against those, and with some luck they will find ways to capture some rodents and fish, or perhaps even a deer or some other bigger prey), so B is solved. What humans do when their bellies are full? Exactly, here comes

T -The Thinking

Something extraordinary has just happened. Up to now, people had to swim, get shelter, and some food, so they were too busy to think about the extraordinariness of this event (and those who tried probably failed at the more urgent tasks). So what happened? Is this a different location on Earth? Are we going to be rescued? Why don't the cellphones work? Is it Heavens (where are my 72 virgins?!) Or is it Hell? The sun and sky seem the same as Earth's sun and sky, so why would anyoune think this is another planet? Maybe when night comes people will realise that the stars and constellations are different; if it is a night of full moon, they will noticed that it doesn't display exactly the same pattern of craters and maria we are acquainted it (how many of those million people would be able to notice that?). Or is the similarity so great that the moon is not only the same size and brightness, but has the same selenography? Is there a place in the Milky Way from where we would see essentially the same sky as in Earth?

Anyway, unless some totally unusual thing shows them that this is definitely not Earth, people will spend what part of the morning they aren't searching for food wondering about rescue, and probably wasting time at trying to bring it upon themselves. Ligthing a huge bonfire, struggling against those mute cellphones, trying to google what to do, writing on the sand, whatever. If other things, such as fauna easily recognisable as un-Terran, or differences in sky (a green sun, two moons, where is Ursa Major or the Southern Cross?) don't help their insights, they will take days, perhaps even generations, to realise that this is another planet.

This is going to affect their strategies. If you realise you are never going to see your homeland again, it is a whole other situation; you are no longer trying to get back to where you come from, and your actions need to be different. But this will be not only thought; it is going to be talked about. Now languages come into issue. You can help a person to get out of water, you can point to a fruit or for something that give some shelter, and language won't be a real problem. But you cannot discuss what this event really is unless you share a language. People who speak relatively uncommon languages will be at a disadvantage now, and only a few languages - Chinese, English, Spanish, Russian, Portuguese, Hindi, Arabic, Japanese - will have really significant amounts of speakers, in the tenths of thousands.

But with talking, comes

C - The Conflict

Now people have material for one of their preferred activities: infight. Doubtlessly, religions explanations will be immediately popular. It is the end of the world, it's the second coming of Christ, God is punishing us, we are the chosen ones (one has to wonder why how many infidels among the chosen, but who wants to get across God and his misterious ways?), on the contrary, we are the damned, repent, rejoice, prepare to die, mend your ways, pray, ask for forgiveness - there is plenty of material for big and small cults, sects, religions.

Such conflicts will have practical consequences, of much more concern than theological ones. Should we move or stay here? Should we explore the hinterland or remain close to the shoreline? Should we try to make boats and explore the sea (are there visible islands that might spark their imagination?), should we go up the river(s)?

From C, evidently, comes

D - The Dispersion

And about time, because we wouldn't like them to suffer overpopulation in an underpopulated world. They will move around, some along the shore, to the North or to the South (or East and West if it is the case), some will go up the river, some will try life in the forest or the mountains, some will get boats and try to reach other islands, some will stay close to the landing point. And this will criss-cross with the languages they speak and with the interpretations they make of the meaning of the Event. We'd rather talk in English about how God is punishing us than listen to the Japanese bragging about being the chosen ones.

Then the size of the new world lands comes into question. If it is a small island, far from the continent and from other islands, they may be condemned to an overpopulation crisis very soon. Else they will disperse and lose contact with each others; in three generations, the Event starts to become legend, the existence of other human groups may become dubious, the idea that they "came" from a different world will become more and more unlikely.

And so they prosper, multiply, and conquer the new world.

Until the next Event. Also known as Volume 8 of the Trilogy of five...

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From the comments below,

However, the one thing that it's missing is technically answering the question - from here, how many generations do you believe it will take before a centralized civilization(s) forms?

Their situation somewhat reminds me of Trotsky's theory of uneven development of capitalism. These people have gadgets produced with ultimate 21st Century technology, but they do not have either the knowledge nor the material or social means to reproduce them. And, worse than that, they miss older technologies too. It is true that a lot of those people will be agricultural workers if the sample is representative of our world. But a modern agricultural worker deals with seeds that have been amply modified by a hundred centuries of continuous agriculture, and it is dubious that they can identify the wild varieties of wheat, oranges, or spinach that gave origin to the modern plants, or that they will have the knowledge of how to grow them - not to talk about how to avoid insects, fungi, and other plagues that may attack their plantations. Or how to grow any plant without additives for the soil.

They will have to try, but that experience will take months, during which people will have to resort to collection, fishing, and hunting. If they succeed, it is then possible that they will have restablished the Neolithic within a year; but that demands that people can feed themselves without agriculture for that period - without agriculture, without many modern tools and without any medieval or ancient tools (a few guns perhaps, but no bow and arrows, for instance), and without palaeolithical knowledge that has long been lost (how to make tools of silex, how to identify the signs of nearby venisom, how to fish with a spear, how to identify poisonous berries and shrooms, etc). So this is going to be a very critical and stressful first year; if they landed too far from the Equator, a failure in that first year will quite likely mean mass starvation, resulting in possible extinction or at least in greately reduced numbers. A tropical setting would be more promising because they would probably be able to survive on collected fruit and roots even during the cooler season.

If they manage to successfully grow plants in their first year, then they will have the basis for sedentary life, and some of them will be settled in villages in a relatively short span of time. It is unlikely that all that population would agree to wait for the success of the agricultural experience without dispersing into the hinterland. Once the coastal groups have amassed some grain, it is quite probable that they would be faced by those who opted for nomadism coming back and demanding some of it, which could spark a first war among them. In such scenario, the nomads, who would have been perfecting weapons for hunt, would probably be in a better position to fight. That could destroy the fledgling new civilisation, and remand all of the new world mankind into pre-agricultural modes of existence.

Of course, recognising useful knowledge and skills will be essential for survival. The problem is that knowledge and skills that are useful nowadays probably won't make any difference in such setting. What good is a IT wizard, or an engineer for people who have to learn how to hunt and how to plant? Even an artisanal smith or weaver, supposing there were some among them, what could they do without iron mines, without lambs for wool, without furnaces and looms? It is possible that people would be better served by an archaeologist who knows how to chip silex.

Worse than that, remains of modern knowledge and technology can be actually harmful. A gun and a few round of ammonition may give people some meat for some time, while delaying serious efforts to develop new weapons - and possibly allowing those who own those guns and know how to use them lopsided positions of power, from which they can actively disencourage research for technologies that would reduce their authority.

So there is going to be a huge crisis in transmission of knowledge to the next generation. Whatever those people know, they will try to pass ahead; but their ability to discern what, from their Earth experience, is useful in the new conditions will be dubious - and those born in the new world may come to reject such experience as useless and fantasist. A great problem will be writing; without proper material support for the activity - and they won't have paper, not to even talk about electronics - and without an immediately visible utility, it may be lost, or reduced to a few individuals that may make of it the basis for a caste distinction, subjugating others to the "magic" of mysterious symbols.

With those caveats, I would say that, with luck, they can be able to retain the technological level of neolithic settlements, and so start from a position corresponding to about 10 thousand years in Earthan past. They will certainly have some objects to remind them of more advanced technology, but if those things cannot be put into use and reproduced - and most of them won't - they will probably acquire the status of magic objects within three or four generations, ie, as soon as there is no longer anyone to remind them that those things were practical gadgets for their ancestors. Development from this early neolithic stage would probably be easier and faster for them than it was for us, but I wouldn't expect them to re-develop metallurgy, much less iron and steel, before several generations; they may have metallic models to inspire them, but the art of extracting metal from ore will be lost and will have to be relearnt from scratch.

Much will have to do with impredictable events - floods, droughts, rigorous winters, epidemics, that could set them back for long times and destroy accumulated knowledge. Nate Silver makes the point, in his The Signal and The Noise, that previous to the printing press, mankind could not even think of knowledge as a long term cumulative process, rather thinking defensively of knowledge as something to be preserved against the attacks of time. If so, the idea of progress, so dear to us, would be lost in the new world, because the printing press certainly would be among those things forgotten in the firts three generations.

In such a scenario, it would be difficult to predict how fast they would move ahead. Anything besides agriculture, perhaps pottery and the wheel, will quite certainly need to be reinvented, because they won't be able to rebuild it in three generations, and from the fourth generation on, the direct connection with the old world will be lost.

From the early neolithic into civilisation, we spent about 5,000 years, or 250 generations, in Earth. If they have a huge enough continent with decent rivers, or an archipel with sufficiently close and numerous islands to move from one another, if they can retain agriculture in the first years, and if they are not decimated by war or natural disaster in the first two or three generations, they should not take longer than that, and would probably be able to do it in a quite shorter time, perhaps "only" a millenium or two. But it won't be a revival of Earth's civilisations; it will be a whole new civilisation (or rather, a whole set of brand new civilisations) built from scratch.

Answer 2

It's gonna be a few centuries

Economy is a function of organization and population size. Losing 60 to 70% of the first million is going to make it hard to recover quickly to 2010-level technology.

In the first five minutes, you'll lose about 44% of your people since the Red Cross estimates that only about 56% of people can actually swim competently. So there's your first evolutionary bottleneck. If you can't swim, you died in the first 10 minutes.

1st Hour

Anyone who's going to make it ashore has done so. One hundred meters offshore isn't too far to swim but fighting with so many people to get ashore will further increase the casualties. Let's assume that another 10% of the original million drown from exhaustion. Combine this with all the random junk that people can get caught up in; this landing is going to make D-Day look like a cake walk.

1st Day

The stench of 600,000 bodies is starting to kick in encouraging the survivors to move away from the landing zone. Water is going to be a huge and immediate concern. Tribes will start forming as soon as people hit the beach. Unification based on language, skin color, dress, whatever, will start quickly. Communication and coordination will play a huge role in who lives and who dies.

1st Week

The dispersal is fully underway. Without agriculture, there just isn't enough food to support hundreds of thousands of people. Food acquisition will be a huge concern. Tribes will spread out looking for food, shelter and safety. Some of the more forward thinking start looking for potential iron and copper sites to start mining for tool production. They'll probably find them.

Survivalists are in their prime.

1st Month

Doctors, engineers and scientists will be in high demand. Doctors to keep everyone alive (as much as they can); engineers to design the new tools that everyone will need; scientists to figure stuff out. As anyone who has a played a survival video game will tell you, keeping yourself alive is hard. Many of the tropes in post-apocalyptic movies will show up. Roaming gangs, murder over bread, war lords, sickness, extreme tribalism. Hopefully, with the lush Mediterranean climate, much of this ugliness won't need to happen.

All of the old trades, blacksmith, weaver, potter, smith, that people did because they were fun as a hobby, find themselves in demand. Blacksmiths rocket to the top of the popularity charts as the people who can make anything.

1st Year

Welcome to the Stone Age! Without any iron/steel/copper tools, everyone is going to have to make do with stick and stones. Geologists will be in high demand to find and exploit iron and copper deposits. Metallurgists and smelter operators can command any price they like because they're the only people who know how to take iron ore into something remotely useful.

1st Decade

A new language has emerged that pulls influences from all the languages of the suvivors. Primitive economies have formed. Trade routes are underway. There's probably been the first plague by this point. Assuming that humanity hasn't sunk into the classic post-apocalyptic downward spiral, I would be making a huge effort to preserve as much knowledge from Earth as possible before the people who know it die off. Gaining that knowledge took centuries on Earth, so the more info/knowledge that can be preserved, the farther ahead these reluctant colonists will be.

With the kickstart of Earth knowledge, it's possible that iron work has improved to low quality steels. Using these crude materials, it's probably possible to make lathes, drill presses and other metalworking machines. Even without specific knowledge of how a machine is supposed to work, an operator will know the behavior of their machines on earth and will work to duplicate those capabilities. Metric measurements will have finally won. Since there isn't any incumbent manufacturing to prevent migration from imperial measurements to metric, there's nothing to stop everyone from finally standarizing on metric. Finally!

Cities and towns have grown up using local materials, styles and preferences. Agriculture has been worked out or there won't be enough people to form a civilization.

1st Century

Population is stable and growing. Adaptations to the local climate and food supplies have finished. Animal domestication is in full swing. Everyone who first came from Earth is dead. Hopefully, they wrote down the things they knew before they passed. With good enough tools, they might be able to get primitive vacuum tube computers. Going beyond vacuum tubes could be tricky since the economy may not be big enough yet to support the kind of capital investments required to allow transistor development.

1st Millenium

Assuming a 1.2% growth rate, the population at the end of 1000 years will be about 60 million or somewhere between 3000 and 1000 BCE (depending on who you ask). Welcome to steampunk Ancient Egypt!

Answer 3

Civilization is People and Processes, not Gadgets

What they have in their pockets and what they carry ashore from the debris is completely meaningless. Civilization stands and falls with having a society.

• They will have to start with subsistence farming. Not enough of the people will be farmers. The realistic answer would be mass starvation and die-offs.
• A random group of people will have some criminals. In a modern society, most citizens have delegated dealing with them to trained professionals. Another random group of people will be cops, judges, prosecutors, but they won't be organized enough to keep the law.
• Who pays the cops, and the teachers, and the sanitation workers? Will the survivors accept the tax collectors when they come around?
• For that matter, there won't be consensus on what the law is and should be.
• Medical professionals will know much more than a tribal shaman, but they expect pills to come out of a bottle.

User SRM mentioned Lost in his comment. Lost were few enough people to form a community. A million is too much without governmental structures.

My Prediction for X plus 10 Years

• There will be fortified villages or city states with outlying villages.
• Roving gangs of bandits in the forests.
• Wooden huts, perhaps even stone buildings.
• Most tools are wood or stone. There will be some surviving tools and a trickle of new production iron (no steel yet).
• They will attempt to produce paper and preserve a written culture, but it will be touch and go. Do they have materials to make paper?

But it won't be entirely neolithic. People accept the concept of democratic government and fair trials, at least in principle. They understand the germ theory of disease, the principle of crop rotation, etc.

My Prediction for X plus 10 Generations

The villages will unite into states. Bits of preserved knowledge will have been implemented (water mills, perhaps steel, perhaps even electricity). They might retain things like algebra and even general relativity, but there are few practical applications for that.

Answer 4

Sorry, but there is high chance all of the people will die or at least enough that any form of civilization is not possible.

Let's go through it in order

• Dropping shocked, clothed, people directly into water with sea currents is recipe for genocide. I would guess at least third of people would die right there.
• Those that will survive this will have hard time following that. Nearby area they landed on will be stripped of any food within hours. And they most probably won't spread fast enough to get into areas with plenty of food. So I would guess next third of people will die within few days from starvation or being killed by other people.
• Their 21 century knowledge is actually working against them. Most people from developed countries don't know how to farm, what food can be foraged from wilderness, how to make even basic tools from wood, stone and plants. Etc.. So even if people will not drown and move into area with plenty of resources, they will be on the level of neolithic.

If you don't want to just kill them all, you should instead grab them calmly from their sleep, place them gently on the ground in area without many natural dangers and spread out enough that people don't compete for resources. Maybe even give them few books on food that can be foraged and prepared without farming.

Answer 5

"Rome wasn't built in a day", goes the popular saying, and it hasn't ever been truer.

Civilisations are formed from the co-operation of thousands upon tens-of-thousands of individuals, each possessing relevant skills and knowledge enough to survive and prosper by converging together - generally under the leadership of a select capable sect - in the name of life.

The people of the largest or strongest civilisations, in almost all cases, originated form the same planetary origins - regions, countries or pre-existing colonies that expanded their numbers by conforming the populous of surrounding locations to their way of life. Their pre-existing social cohesion acts as a foundation for further empirical growth, which without would see any hope of a greater civilisation fall to pieces (there being no trust or structure or purpose among it's members).

Simply dropping a million persons, from all regions of the world, with very little in common in the way of cultural likeness, language and beliefs, is a recipe for civil destruction rather than growth. By simply looking at humanities judgments toward each other, to those ethnicities other than oneself or social minorities today, it becomes apparent that this will be no leisurely journey...

Dunbars Number refers to the theoretical limit to how many relationships a person can maintain at any given time, derived from the regular brains capacity for storing information; every single relationship made will count on this planet. These million people (or those who survive the initial splash down) will form instant connections with those they relate to on a more personal/cultural level, immediately dividing the future-civilisation, for despite them all being in the same survival situation, pre-existing bias/barriers still exist; this will need to be over-come if there is to be any chance at colonial development.

The skill range of these people will also need to be taken into account; by law of distribution, almost no-body in the million will possess the skills relevant to survival (accounting or quantum-physics not exactly the most helpful...), potentially thousands having no knowledge on life at all (being children or un-educated) and those who do will be limited in who they associate with to begin with...

This civilisations best hope comes in the emergence of a clear governing body, a caucus of people who share the essential knowledge of survival - hunting, farming, construction, human resource management, health care- who will be most qualified to lead the masses; but as explained, this will be no easy task and could potential prove to divide the emerging culture more.

So.

This established, how long will it take?

In a word entirely devoid of usable power, functioning technology, advanced tools and appliances, basic shelters, readily attainable food sources... Civilisation is going to take a while to take off.

If a leadership group emerges, it will most likely only get a small fraction of the million to co-operate, humans being largely self obsessive, the rest resisting to form their won splinter "alliances" with those people who most resemble one another in ethnicity, language, culture or belief system. This isn't such a bad thing though, provided violence remains frowned upon and any who commit "felonies" are dealt with according to judgement of the majority (hence the beginning of a justice system).

The groups would live in relative proximity to one another, forming ever more intricate housing over time, as people learn from their leaders or from experiencing failure (the gathering and distribution of essential knowledge); any non-vital information will be forgotten over time (as those who held it die/ find it irrelevant).

As groups form alliances with their closer neighbours, they may merge, this process continuing over the course of generations until there remains only one sole community of which internal social sects (the original groups) provide a different skill set or value to the civilisation as a whole - just as modern day people live and work.

Answer 6

I'm a bit more of an optimist. If you were lucky and had a few people who stepped up and were experienced and talented leaders with an immediate vision (e.g. someone experienced leading large military units to organize aid following major natural disasters), it might be possible to get a critical mass of people into a series of large organized chiefdom polities with perhaps several hundred to a thousand people each quite quickly. And, the bigger the short term initial groups are, the less time it takes for them to consolidate with each other into something resembling proper nations.

Normally, it is hard to get people to coalesce around a leader, but in a total vacuum of leadership or society organization, it is amazing how many people one leader can get to follow their lead spontaneously.

For example, I have run large (several hundred attendee) political caucuses in Presidential election years on several occasions. And, most people have no clue what to do. But, if you shout clearly and loud enough to be heard by everyone in earshot and act like you know what you are doing, and quickly draft a few people who aren't totally dazed to be your lieutenants, you can bring a gathering that large to order remarkably quickly because in the situation, nobody resists your authority that you establish in mere seconds.

I've either heard described, or seen with my own eyes, similar feats of mass crowd control at political rallies, rock concerts, boy scout jamborees, military exercises, religious gatherings, sporting events, a beach full of people where someone has figured out that a tsunami is imminently en route, and in cities facing imminent air raids or attacks in wartime.

A loud voice and communication of a clear vision from someone who sounds like they know what their doing can go a long way, as long as the vision holds out.

The trick is, however, that for this to work, the would be leader has to seize authority over a large group while everyone in that large group is atomized and hasn't had time to form localized alliances and factions with their neighbors. If this happens enough times in the first couple of hours, the cause of civilization will be advanced by decades. If it doesn't, it will be a long slow haul.

Answer 7

I'd also recommend reading "Why the West Rules (For Now)" and any other work which tries to put history in a broad context. It talks about the major developments required for civilisation to start up and move to the next step.

I'm not going to talk about any of what happens regarding immediate arrival, since people have come up with some amazing answers regarding that, but rather, talk a bit about some of the major milestones that affected Civilisation that are worth thinking about.

So, @LuisHenrique pointed out that the biosphere has been heavily modified by human interaction. This is true. One of the really interesting things about the development of early agriculture, when we went from hunter-gatherers to the first settled societies (with the largest urban dwellings being villages) was that it involved (at least in the Western parts) a mutation involving grain that wasn't useful for it but very good for us. Similar mutations in rice kicked off the Eastern civilisation a bit later and similar things happened with squash, potatoes etc elsewhere.

Also domestication of the first animals and the selective breeding to ensure they become more useful caused animal agriculture to become useful.

Have these happened? What is the available biosphere? Depending on your choices, it's possible there's nothing anyone can do to achieve a standard of living better than hunter-gathering. Additionally, I don't think the earliest crops or domestic animals were very wide-spread. Depending on the exact nature of the biome make-up and the spread of crops, gathering the necessary stuff could be easy or impossible hard. Whether the society ever gets beyond hunter-gatherer would strongly depend on that.

I notice you say 35 degrees north and that's interesting, because if you're feeling kind, the easiest start you can give them is the Turkey/Syria Hilly Flanks region. Off the top of my head, that small region is 11 of our world's staple food crops and animals, which, while the best of all the places agriculture started independently on Earth, isn't a wide variety of food and animal labour. Next best is China, I think, and it took Roman times until the crops from one centre of civilisation crossed to the other.

Still, assuming you do give people a good chance in terms of available species, I'd imagine the jump to farming would happen very quickly because people would know to go looking for these things (if they exist) and would probably pass them on quite quickly, which was the limiting factor in their earlier spread. It's also worth noting that wild animal populations will not be low like they are now, so traveling will be dangerous.

The next stage detailed in the book involves large major irrigation projects on large rivers. So, it assumes you have large river systems to do irrigation on and the technology to organise society (writing, social methods of cohesion not just involving force), which might get retained if the population can get through the previous stage quickly enough to preserve knowledge.

One of the super-useful things speeding up civilisation will be the lack of disease as a civilisation ending thing. One of the very damaging things that happened was when various independent centres of civilisation started exchanging their diseases with each other. While everyone knows about the colonisation of the Americas, the same things happened between Western and Eastern cores earlier (with just as much death) and at least one reason America was so screwed was that it got both sets of diseases, not just the Western ones. In this case, you probably wouldn't get that, even if people separated for a hundred years or so. Yes disease would be present and increase as medicine collapsed, but you wouldn't get the damaging plagues of mass death. This would rapidly speed things up.

Answer 8

Hard to give a definite time frame but I will try to give it my best guess.

First week many people die because there don't have the skills to survive in the wilderness.

Second and third week. People begin forming into small groups to share skills and resources in order to survive.

First month the groups become hunter gather tribes.

Second year people began experiment with growing plants.

Fourth year people have built successfully farmes and are forming villages.

One hundred years. The villages have grown to form small city states.

Answer 9

Ever throw a banana to a group of monkeys? The monkey who catches the banana doesn't have a friend in the world. It's every monkey for himself. It's rather hilarious entertainment.

At the end of the first week, the people who make it to the shore will be in the same condition. After the first time they are robbed of their catch and left with nothing, the survivalists make sure to eat their fill before bringing anything back.

Then when they bring back less than the last time, the self-appointed leaders of the community will accuse them of hoarding. This will lead to quarrels and manslaughter.

The survivalists who aren't killed in this will say, "forget this noise," and leave, taking with them the most attractive member of their preferred sex who agrees to go with them.

Everyone else either learns what the survivalists already knew, or they starve.

Your million people will be around a thousand by the end of the second month.