A news article recently caught my eye, it was about various novel methods that are being used to combat invasive species; i.e. animals that have taken up residence in a place where they simply don’t belong.
Here where I live, there are scads of “stink bugs” that apparently came from China in shipping containers, only chickens will eat the stupid things and they are a real pest. But that’s a comparatively minor problem. Australia has an issue with rabbits, the Galapagos islands have goats, numerous species of birds in the Pacific were made extinct by cats, the list goes on into infinity, really.
It’s also not a new problem by any means. Human populations have been dragging around their companions world-wide since the dawn of time. Chickens to England, the horse, the dog… the list goes on. And let’s not forget about our microbes. A certain flea brought the ruinous Plague of 1346 to Europe, the infected beasties probably came into Italy with shipments from the Silk Road.
So if the day comes that we finally leave this planet and go out into interstellar space, I think it’s inevitable that we will bring our companion creatures with us in some form. Whether they sleep off the trip in the cargo holds or are brought into space as frozen embryos, you can bet your bottom dollar that our most useful animals will be brought along for the ride.
If we don’t bring animals, we will certainly bring our microbes.
It’s a subject that has been brought up a lot in science fiction, how we may impact the ecologies of new and presumably pristine worlds. I think that if we scout out other worlds and they are marginally inhabitable, humans will settle and colonize said worlds.
It’ll get interesting when we start getting answers to questions such as whether we can assimilate alien protein, whether “alien” protein can assimilate us, and whether diseases can be spread across non-native populations.
Heck, it could be that humanity spreads across our relatively close by star systems and no-one can really travel because of quarantine concerns.
I think that the definition of “human” would certainly change as hundreds, then thousands of years go by and all the different populations specialize to adapt to their respective worlds.
In such an interstellar civilization, I shudder to think what your immunization record would look like as you flit from star system, to star system.
And there would probably be a race, call it homo sapiens stellae, who would specialize in traveling the stars. They would be interstellar vagabonds, specialists who would travel the vast voids. Think of them as the truck drivers of an interstellar human civilization.
And yes, the invasive species problem will continue to be an issue. Only on a much grander scale.