Peak oil is pretty scary. Modern agriculture requires 10 calories of energy to produce 1 calorie of food. Then you need to transport and refrigerate the food. Our whole civilisation depends on cheap fossil fuel energy. We have already used up about half of the total supply.
However, long before we run out of oil, climate change from burning fossil fuels will make the planet uninhabitable. We will have to leave most of the rest of it in the ground. In other words, we have to learn to do without oil much sooner than we thought. If we cannot think of something better, the default way to handle it is a massive population crash, the same way nature handles such problems.~ Roedy (1948-02-04 age:70)