More fun with the End of the World
- Climate change
- Telomere erosion
- Viral pandemic
- Nuclear war
- Meteorite impact
- Robots taking over
- Cosmic ray blast from exploding star
- Earth swallowed by a black hole
Some of these are more likely than others, and some would have more serious consequences than others. The weirdest item on the list is number 7, in which super-intelligent robots take over the world. (I was unsurprised to find Hans Moravec as the author of this one.) The most unexpected was number 2, in which species face extinction due to a long-term degredation of the telomere structures at the ends of chromosomes. (I guess sharks and cockroaches must have some pretty rugged telomeres.)
But for my money, the most interesting item was number 9. Many times over the last few million years, the Earth has experienced volcanic eruptions that are orders of magnitude larger than anything with which we are familiar. One of the most fascinating examples was the explosion of Mount Toba in Indonesia around 70,000 years ago, sending thousands of times more material into the atmosphere than Mount St. Helens did. This could cause catastrophic climate effects for years. There is apparently some genetic evidence that human populations went through a "bottleneck" at that time -- in other words, that something reduced humanity to only a very few individuals. About 70,000 years ago, the theory goes, Homo sapiens almost went extinct due to a "volcanic winter".
The Guardian list is not exhaustive, of course. Alien invasion, civilization collapse due to resource scarcity, and collision with rogue planets from interstellar space all have scientific or science-fictional pedigrees. So do less-familiar disasters like universal loss of human fertility and mass biorhythm disfunction. (The last, as I recall it, can be precipitated by a cosmic censorship principle against the invention of time machines. See "Rotating Cylinders and the Possibility of Global Causality Violation" by Larry Niven.) One can mix and match elements -- invasion by alien super-intelligent robots, who create climate change leading to international tensions and then nuclear war. What a plot-line for a fat paperback novel!
Are there others? What have we missed?