> In the last 550 million years, there have been at least 5 mass extinctions in Earth's history that killed over 70% of Earth's species.
And our ancestors survived them all. Without being able to put concrete around them, to store food and water, to predict the event, to fly to more hospitable areas, and so on. Also, if any of these events had turned Earth into worse a place for life than Mars, then there would be no life on Earth right now.
There really is no reason we could not survive any event comparable to what happened in the past.
Humanity will likely survive the next mass extinction
> the Sun is going to kill off all multicellular life on Earth within the next billion years or so.
It's absolutely ridiculous to worry about anything occuring in such a time frame.
« although global disaster is all but inevitable, our chances of long-term species survival are better than ever »
http://www.amazon.com/Scatter-Adapt-Remember-Survive-Extinction/dp/0307949427