Is it possible for 2 human beings to repopulate the earth to a population of 6 billion?

Question

If so could it be done in 10,000 years?

Answer 1

...NO.....I do not think so....if just 2 human beings must populate the earth in so little time up to a population of 6 billion...think of how many kids a day they must have....assuming male and female ok....if a regular pregnancy takes 9 months you can only have 1 kid per year or mmm...now...you have to wait until they are mature enough..that will be assuming that you get one boy and one girl...now ...you have a son (brother) and a daughter(sister) having sex to reproduce...isn't that sickening...

Now...think of this....let's assume that couple came to America in the 1900 they had 4 kids...ok 16 kids... and they are 1 year apart ...8 girls and 8 boys and every one of them got married at a early age..mmmm 16. and 18 ...and keep on thinking....how many family member will be in the year 2000...I do not think this particular family will end up with 6billions family members in 10 k years...so I think this theory is null....

Answer 2

If the two starting individuals were genetically diverse and not carrying any recessive genetic disorders, then yes.

Say Swede and an Australian Aborigine to be give a wide possible range of traits (although all humans are surprisingly very homogenous on a genetic level)

Say the population were to double every 72 years

2,4,8,16,etc

It would take far less than 10000 years. More like 2300 years

Creating and sustaining poplulations of billions have more to do with technological ability to feed and equip and transform marginal lands into liveable ones than ability to breed.

The biggest issue in your question is having viable stock to begin with. Millions of pure bred animals exist and they have extremely limited genetic diversity, and even if some of your sample humans did not fare as well, the more healthy ones would certainly pick up the breeding slack.

Plus random mutations occur all the time and can add to the gene pool.

Answer 3

All you have to do is look at how the Earth's population has exploded in just the past century. Of course it's possible, mathematically and physically.

It's the same concept as accepting a job for a penny on the first day, working for two cents the second day, four cents the third day, sixteen cents the fourth day, etc. By the end of the month, you'd be earning really big bucks! By the end of the year, you'd be a millionaire!

If you're trying to determine that the Earth is only 10,000 years old because it all started with Adam and Eve, it's important to assume that a "year" in God's eyes could have been any amount of time - not the 365 days we think of as a "year" today.

-RKO-

Answer 4

Well, we somehow got to 6 million. Assuming humans had children during a 20 year window at 1 every 18 months and half lived to child-bearing maturity, that's a progression of 6 children first generation, 36 children second generation, 216 third generation, 1296 fourth generation, 7776 fifth generation, 46,656 sixth generation, 279,936 seventh generation, 1,679,616 eighth generation, 10,077,696 ninth generation, 60,466,176 10th generation, and so on.

Now using the standard genealogist's 25 years per generation, in 10,000 years there are exactly 400 generations. So, if you can get to 60 million people in 10 generations I would think the progression calls for several billion after 400 generations.

My problem is the original 2 would give rise to 6 siblings, and we all know what happens when sibling interbreed, we get mongoloids and other genetic niceties...still assuming enough survived and interbred it seems likely that a population of two could get to the 6 billion we have today.

So I think its mathematically and genetically possible.

My initial assumptions of 6 children surviving a 20 year breeding span may be off. I'm assuming 20 years fertility, because I would think that one did not live much beyond 40 and assuming a child born every 18 months with half living that it results in 6 children making it to sexual maturity. One would have to factor in premature death and other factors which would account for fewer surviving children and then one has to factor in death rates to refine the number.

Answer 5

I think that genetic has an answer what is the minimum number of people that could make enough genetic diversity to repopulate or populate a system withoug going in to posibility of genetic defects in their ofsprings.
Under todays science 2 people without source of other genetic material can not make such a population.
You would need to leave social tabu of sex between relatives, brother and sister, brother and mother, sister and father, and their offspring tend to have seriusl genetic defects.
But I could be wrong.
If I should guess then minimum is some 40 pairs of man and woman, but I am not an geneticist.
So I hope someone will give you an better answer.

Answer 6

Yes, it's very possible. I'm not going to use Adam and Eve as an example, but look at other creatures and how they started with one and now there are millions.

If there are 2 people (um... assume man and woman), and they have as many kids as possible in their lifetime, and their kids have as many kids as possible in their lifetime, and so on, the population can theoretically reach any number rapidly. Could it be done in 10,000 years? Sure. Ok, 10,000 years ago, humans started farming and settling down in communities (Neolithic Revolution, 8000 BC). How many humans were there then? Not many. And look at how many there are now. Also, consider that the decendants of these two people will be TRYING to have as many babies as possible. Yep. It can be done, assuming, of course, that there's an equal chance of having a boy or girl.

Answer 7

At present the population doubles every 35 years.
Take 2 to the power of (10000/35) and you'll see that it's possible.

But consider, if you're a Christian Fundamentalist, then the great Noachian flood happened about 4000 years ago. Could eight people populate in 4000 years? Again, the answer is that it's possible.

Answer 8

OK, it is perhaps mathematically possible, but it is absolutely impossible if you also include the magnitude of the genetic diversity that we currently see in the human species. Two people simply could not give rise to 1.2 Billion Chinese and at the same time 450 Million Africans in only 10,000 years, as an example. And who would be there be to tell the Chinese grandchildren to all go and live in China and all the African grandchildren to all go and live in Africa? So the thought is totally ludicrous.

Answer 9

Mathematically, is a reasonable birthrate enough to do it? Absolutely.

In 32 generations (about 800 years) if 4 children survive to adulthood in each family.

In 14 generations - about 450 years (longer fertile period) - if families have 10 kids like my Irish ancestors did.

One problem would be infrastructure. The metal, fuel, and technology needs to develop to get past pre-industrial levels of 500 million or so.

And some folks need to be willing to take some seriously risky ocean voyages to populate all the continents.

Genetics aren't a huge issue. If you have 5 kids and one in each generation has a fatal condition due to inbreeding (pessimistic, even early on), 4 kids still survive. And that condition is then less common. Thousands of tule elk in California were reestablished in a dozen areas from a single pair that a rancher saved 100 years ago.

Most likely scenerio: 10 to 20 million people on one continent within 1000 years. Beyond that it takes unlikely events by unusual people (migration, technical innovation) and that is hard to predict. If CULTURE could be passed on, knowing what was possible and what lay over the ocean would accelerate those processes.

Answer 10

10000 years is 500 generations

2 to the 500 power is how many people would have born . 2 to 488 power would be dead. That is 150 digits long

In short if everyone had 4 kids and died after having grandchildren. You would have 9 billion people in only 36 generations. At 20 years per generation, that came out to 720 years.

Good thing for war and plague

Answer 11

As a religious person I'd have to say yes it's been done before but with the people around today no it's not possible. Adam and Eve were perfect and there children were pretty darn close to it because of there parents. That is why inbreeding was okay because there was not imperfections in there DNA to pass on, no risk of two recessant genes getting together and causing the kid to be born "unhealthy". Today we are so far from perfect that you could have children with someone on the other side of the planet and your kid could end up with just about anything