I’ve never been a huge fan of colonizing other planets. I support colonizing other solar systems.
There’s so much involved in building a generation ship with any decent chance at all of success that we’ll have learned a whole lot about living in space, building stations that are as close to self-supporting as we can, mining asteroids for materials, and in-space manufacturing. All of that would be applied to a generation ship, and I’d expect them to start setting up an in-space civilization once they arrive. No need to learn to deal with a novel biosphere right away, just replicate the systems we have in Sol.
I’m sure someone would set up on the planet eventually, even if just as a Disneyland resort kind of thing. But the main civilization will live in space. By the time they get there, their society will be a space-based society. They won’t have our built-in prejudices towards thinking only planets are “real” homes.
Unfortunately, I suspect that even a superficially similar biosphere would be unpalatable. We might have to go a very long way out there to find something to eat.
I thought the Martians were looking for a few good men.
Seems to me every SF book I’ve read that deals with the first colony on a new planet assumes that they won’t be setting up at back-home tech levels. Usually it’s about 18th- or 19th-century level – animal-powered transportation, no fancy electronics, &c
It depends on how rapidly the population could expand, so that the fewest possible genetic lineages go extinct and the most cross-combinations can take place. If the population stays low or only expands very slowly for too long genetic variety takes a hit.
I’m not finding it now but there was a thread about the genetic difference of “double cousins”, the children of two brothers marrying two sisters, and how that wasn’t as narrow a bottleneck as two twin brothers marrying two twin sisters, even though the resulting children all share the same four grandparents.
I’m not a biologist (much less an exobiologist), but AIUI the question whether there can be biochemistries that are fundamentally different from ours but behave in a similar way is a very controversial one, and one that pops up a lot as a popular theme in in sci fi. You need a solvent for biomolecules to dissolve in, and water has great properties for that, so it seems reasonable to assume that there’s a fair chance an extraterrestrial biochemistry would be water-based; the standard alternative presented in sci fi is ammonia. Similarly, you’d want an element that can bond easily with other atoms as the basis for your biomolecules, and carbon has that property, so the chance isn’t so bad that another biochemistry would be carbon-based; the standard alternative in sci fi is silicon.
Larry Niven in his “Known Space” stories postulated that all the life in our galaxy is descended from the same panspermia algae that were sown across every young solar system three and a half billion years ago by now-extinct predecessors.
Interesting discussion. I’m not wedded to the precise number of people, the point of this thread is also to find out how many you’d need. Hadn’t thought about genetic diversity.
I wonder what level of technology would be feasible to aim for (to be able to reproduce). As said above by someone else, 18th-19th century may seem adequate, as there was at that time not yet a very advanced/complex infrastructure.
Even pre-industrial there’s a LOT of specialization of skills and diversification. Look at every European name that comes from a traditional occupation.
All true; but even if the biochemistry is carbon/water based there are plenty of potential ways to arrange biological macromolecules into lifeforms. For a start there are mirror-imaged molecules that would make the life useless as food, different DNA codons and amino acids, and a wide range of potentially toxic trace elements; compounds that could kill you or provoke an allergic reaction, and on and on.
This is also true. Earth is pretty nice, because it’s very difficult to sabotage it (deliberately or accidentally) to the point that it’s completely impossible for human life to exist anywhere on the surface. But that’s not likely to be a common situation: Any other planet is probably going to need either some ongoing systems or some serious terraforming action to get to that point.
Sure, (probably) water and carbon compounds. I’ll even spot you trace amounts of nitrogen, phosphorous, and several other elements. But there’s still a huge amount of variety possible within those constraints.
Besides chickens and maybe pigs, take along sheep for wool and horses for horsepower. Sheep and horses can also provide meat, leather, and milk. I’d bring all mares and ewes, with several different stallions’ and rams’ frozen semen and the equipment for artificial insemination.
It would also make sense to bring herding and guard dogs to protect people and livestock from native predators.
This all assumes, of course, a ship that could transport sufficient livestock and a planet with forage edible for the grazing animals.
ETA: Oh, and then you’d need spindles or spinning wheels for making yarn and thread, and looms for weaving cloth. Also needles and scissors, lots of them.
On the other hand, if there were a biosphere on this planet completely compatible with Earth life, it would be somewhat unethical for a group of colonists to go there and attempt agriculture. Unless life-bearing worlds are very widespread and commonplace, every distinct biota should be conserved as completely as possible.
And certainly don’t introduce any rats, rabbits, rhodedendons, or knotweed.
I don’t think that livestock would be a problem. We’re bringing humans, after all. And livestock populations can be increased much more quickly than human populations, and in ways that would be ethically questionable for humans.
Rhododendrons? I’ve heard of issues with all the others, but I’ve never heard of rhododendrons being invasive.
Anyway, any extraterrestrial (so to speak) plant is likely to either die or quickly or be invasive. It’s not like any of them would have biological checks. Grass is incredibly invasive, for instance.
Head for head, horses take up a lot more space than humans, even if the colony ship had some kind of cold sleep/suspended animation. But as you point out, increasing the number of usable livestock would go a lot faster than population expansion.
Not necessarily, depending on how much time you can take to get the colony up and running. Bring live miniature horses, which are about the same size as humans, but which are still the same species as Clydesdales. Then, each generation, implant embryos from varieties that are a little larger, until you have horses of the size you actually want.