It looks like you're using an Ad Blocker.
Please white-list or disable AboveTopSecret.com in your ad-blocking tool.
Thank you.
Some features of ATS will be disabled while you continue to use an ad-blocker.
A new study has calculated how many people it would take to viably populate another planet.
In the future we may see generational ships heading out across the stars on voyages lasting thousands of years in the hopes of finding new Earth-like worlds to colonize.
Back in 2002, anthropologist John Moore calculated that such a ship would need at least 150 people in order to survive a 2,000-year trip across the cosmos, but is this really enough ? A more recent study conducted by Cameron Smith or Portland State University has cast doubt on this conclusion and suggests that a more realistic number to ensure survival would be between 10,000 and 40,000 people.
These figures were reached by taking in to account the necessary genetic diversity of a population, the possibility of disease or disaster along the way and the likely growth rate from natural births.
"I did this study to materially help in putting together the millions of puzzle pieces that will be required to allow humanity to spread out from our earthly cradle," he said.
Gardner-O'Kearny calculated each population's possible trajectory over 300 years, or 30 generations. Because there are a lot of random variables to consider, he calculated the trajectory of each population 10 times, then averaged the results. (With one exception: The starting population of 40,000 is so large that it takes 18 hours to complete each simulation, so he calculated that trajectory only once.)
Genetic diversity keeps groups healthy, and larger populations tend to have more diversity. In small or isolated groups, including Ashkenazi Jews and the Amish, marriage between relatives has reduced genetic diversity and made otherwise rare diseases such as Tay Sachs and cystic fibrosis common among those populations. Graph A shows that Moore's suggestion of 150 people is not nearly high enough to maintain genetic variation. Over many generations, inbreeding leads to the loss of more than 80 percent of the original diversity found within the hypothetical gene.
A population of 500 people would not be sufficient either, Smith says. "Five hundred people picked at random today from the human population would not probably represent all of human genetic diversity . . . If you're going to seed a planet for its entire future, you want to have as much genetic diversity as possible, because that diversity is your insurance policy for adaptation to new conditions."
A starting population of 40,000 people maintains 100 percent of its variation, while the 10,000-person scenario stays relatively stable too. So, Smith concludes that a number between 10,000 and 40,000 is a pretty safe bet when it comes to preserving genetic variation.
The second threat to interstellar voyagers is catastrophes—plague, war, collisions, and mechanical failures—that could wipe out large portions of the population at any time.
When 10,000 people are housed in one starship, there's a potential for a giant catastrophe to wipe out almost everyone onboard. But when 10,000 people are spread out over five ships of 2000 apiece, the damage is limited.
To make interstellar travel a reality, scientists and engineers will have to overcome huge obstacles. They'll need to find ways to increase propulsion speed, prevent the negative health effects that arise from living in space, and devise self-sustaining systems that provide food, water, and air. At least the new calculations provide some sort of starting point.
"With 10,000," Smith says, "you can set off with good amount of human genetic diversity, survive even a bad disease sweep, and arrive in numbers, perhaps, and diversity sufficient to make a good go at Humanity 2.0."
NowanKenubi
hm... Why was I told 25 males and 25 females were needed to insure the survival of a specie?
That's a lot lot less than 10 000, or even 40 000 people!
The idea of sending multiple ships is indeed a better way to insure the arrival of as many people as possible. Until technology allows to send 40 000 without any major risks.
Rainbowresidue
reply to post by Shadow Herder
Good point!
But can be avoided easily just by having 'History of Mankind' book available to them. Which I'm sure they will.
With the scientist they could also send a theology scholar up, to make sure we have their history/ evolution/ religion covered.
I'm pretty sure the human history part would be for them to read and available though. That's very important.
\\
benrl
Well...
Thats sticking to todays societal and moral norms.
Could easily be accomplished with A.I.s and or a few people, and frozen egg and sperm in the very near future.
Send an A.I. or a sufficiently advanced drone that could be updated remotely...
Shadow Herder
\\
benrl
Well...
Thats sticking to todays societal and moral norms.
Could easily be accomplished with A.I.s and or a few people, and frozen egg and sperm in the very near future.
Send an A.I. or a sufficiently advanced drone that could be updated remotely...
Maybe we arent meant to travel to faraway places just as cells that construct the flesh on your butt do not belong with the cells in your brain.
Shadow Herder
Do you consider the bible or other ancient lores as definitive history?
anon72
First thing they have to do is how to save human reproductive elements from
radiation bombarment once they leave the earth astromphere.
But, it that is possible you will have millions trying to get the hell of this planet and that would be there opportunity.
The Good, Bad and the Ugly would all be out.
Just a chance to get out from the thumb of danger from the less.... desired of our population.
You know the ones who are preditors and target humans.
Rainbowresidue
Shadow Herder
Do you consider the bible or other ancient lores as definitive history?
No, I don't. Not at all.
Keeping up with our HISTORY would be more important. And by that I mean our history.
I'm not a religious person, spiritual, yes, but not religious.
(Evolution, ancient civilization, how we came to build/invent A to Z, etc.)
If you are looking for a religious answer, you asked the wrong lady.
edit on 9/4/2014 by Rainbowresidue because: Spelling,because it's Wednesday.