In many Science Fiction movies there’s one plot device that, like a broken down show pony forced to perform despite old age, is dragged out time and again to strut its stuff. That of the Earth being ‘Doomed’ somehow by mankind through overpopulation or environmental disaster. Something that only a ‘hero’ can ‘save’ a sacred few from. It was a tired idea by the 18th Century CE (Seriously) and it’s worn to a nub of nothingness now. This premise is what’s put me off going to see the movie ‘Interstellar’.
In looking at possible (or impossible) futures I’ve always found it a good idea to examine what has sparked human migration since our species first learned to walk upright. From observation, the biggest motivator is that the grass will grow greener over the next hill. Fresh ground to occupy, new resources to develop, new ideas to explore. It’s part of the human condition. Only in the very early days of bipedal endeavour has environmental disaster played a significant role in mass migration. In the more modern era, migrations tend to be generated more by politics, war and economics than simple resources. To illustrate by analogy; when the fattest of cats have locked the dairy, the kittens will go elsewhere for their cream. And they will cross continents, even galaxies if the means are available.
It’s also worth noting that most of us simply want to get away from our parents and make our independent way in the world. Visit other places, learn other languages, meet other peoples. It’s been part of the human condition ever since we evolved to spread out a little. Mate, carve out a patch for the next generation and expand. If anyone were to ask me the meaning of life, that’s how I’d describe it. The Earth may well be our mother, but frankly wouldn’t it be embarrassing to tell other intelligent life forms that we still live in her basement?