Fine Structure

Species Survival and Risk

There's a brief article in Discovery News last week about a lecture by Stephen Hawking about "alien quiz shows." While the main focus was on the possibility of contact from another species across the stars, Hawking did manage to work a subtle ending on the topic of planet colonization which is something I feel our species should consider as an important next step.

Our biggest fears as a species are the ones that effect the entire planet. Global warming, nuclear war, killer asteroids - these things make the front page at the slightest mention. Although we think mostly about our own personal safety when these types of disasters are mentioned, what we should really be concerned about is the survival of our species as a whole.

If you think about this with a scale-through-history perspective, expanding to other planets and solar systems is a natural progression. Imagine of a prehistoric culture on an island with limited boating technology. This culture is at risk of complete extinction by events which are not uncommon. Volcanic eruptions, particularly strong hurricanes, localized drought. Depending on their location, any of these things may be likely to occur over the course of 50-100 years. Our theoretical island-culture can increase their chances of survival by developing boating technology and expanding to the mainland or another island. Boating technology protects them from a number of slowly moving disasters even if they don't immediately expand elsewhere. And as this culture expands, it's total population is under less risk from natural disasters.

Once this culture expands to the mainland, they may still be at risk of an ice age if they can't expand southward in the event of such a change. This event is much less common, possibly two orders of magnitude less. You can see that our theoretical culture has just increased it's chances of survival by giving itself a good deal more time to develop the technology to move to warmer climates if necessary, something that it would have been powerless against initially.

In this same way, we're at risk from many of the global threats because we don't have the technology to move any great number of people off the planet in any sustainable way (sustainable being the key word). We have the technology to take a few of us to the moon (not that we have recently) but the moon is hardly sustainable for 3 people, let alone a good chunk of our 6 billion humans.

One of our options is to develop the technology to live on some previously-inhospitable rock (mars, moon, etc). We would somewhat significantly reduce our risk as a species and we would need to develop terraforming technology or start making those bubble-cities you always see in science fiction. And, of course, we would still be threatened by solar-system wide disaster. Unfortunately, I don't know enough about our solar system to accurately judge what disasters could effect our entire solar system and at what scale. Perhaps we're taking about the estimated life of the sun, which we have a possible 4 billion years left, or something less predictable, like an errant black hole swinging our way and gobbling us up.

The other option, and one which is only limited by the heat death of the universe itself, is to develop the technology to travel between solar systems and expand across the universe. This is what Hawking alludes to in the end of the article. The likelihood of a disaster that effects the entire universe is so small that our species would effectively be guaranteed survival for the better part of forever. And this brings up some interesting questions - will we find something similar to earth or do alien civilizations really entail something we haven't yet imagined? Fortunately, we have a little while to think about these things as the technology to go beyond our solar system in a reasonable amount of time is developed. However, this is our only way to make sure the human race lives on indefinitely. With our expanding population and shrinking available space, this should definitely be something our species should aspire to.