What do we do about the population crisis?

Only with draconian “one-child-per-family” laws can there be a realistic slow-down in the current exponential growth rate. It is highly unlikely that that will occur voluntarily. Besides, the one example where that was attempted (China), doesn’t exactly give me a positive feeling that it could be successful even if applied everywhere else. Our species appears to have a genetic predisposition to “be fruitful and multiply”, even if that concept wasn’t enshrined in the religious texts and teachings of several of the dominant religions (which it is) - and which incorporate the vast majority of humanity. I strongly believe natural processes will solve the issue for us. Catastrophic ecological disruption (or ecological collapse) is a very realistic scenario, in my opinion. We’re talking a biosphere-level “reorganization” whose results would be a disaster of biblical proportions from our point of view. It is interesting, however, to speculate on what a putative xeno-paleontologist a few million years hence will see in the fossil record. Will there be an identifiable “boundary layer” between the Holocene and the Whatever-comes-next-ocene? Or will there simply be evidence of a species that went extinct, as so many others have done? Of course. I don’t want my kids to face starvation and global warfare over increasingly scarce resources. On the other hand, it’s not entirely clear what the options are at this point.

You have an excellent point, rand. Unlimited, renewable, free (or at least really cheap) energy could go a long way to staving off a biotic crisis. Assuming, of course, there was some way of quickly converting the entire planet to the new energy source.Unfortunately, without a concurrent curb on the population growth rate, we're likely to see a doubling of the total population in the next 40 years. Even if the Total Fertility Rate declines to sustainable levels (2.1 per family globally), the statistical "delay" will pretty much guarantee 11-12 billion people on Earth by 2050 (all other things being equal). A perfect energy source and technological advances may make that livable. Here's an interesting chart showing an "optimistic" view. (Source: World Population: Major Trends)Note that the TFR DOES decline to 2.1 (or slightly less) over time, yet the population continues to grow regardless. The ecological footprint of that many people attempting to use increasingly scarce resources (i.e., arable land, potable water, etc), is going to be immense - and even with really radical technological advances, may or may not be sustainable.However, energy is a great first step. Well thought.