Pearce chronicles nearly 200 years of demographic issues, beginning with efforts to contain the demographic explosion, from the early environmental movement's racism and involvement in eugenics to coercive family-planning policies in China and India.
As it turns out, population control has been naturally occurring on its own. In countries all over the world, birth rates are on the decline as woman choose to have 0 to 2 children, which is near or below replacement rates. The reasons are not by design, it just sort of happened, a result of increased affluence and urbanization brought on by the green revolution of the 60s, and increased access to and awareness of birth control. Given a choice, women don't want big families, they'd rather invest resources in a few healthy children and pursue their own life interests. The numbers tell the story and Pearce's book is full of page after page of amazing perspectives that totally changes how one sees the world. In short, most likely we will reach "Peak Population" by 2040, that is, the total number of humans on the planet will peak at around 8 billion and then begin to decline, rapidly. There are already some days on planet earth when more people die than are born.
Pearce has written a fascinating and optimistic book, we really need it in this time of gloomy predictions about the future. Demography very well may be the saving grace of the human race. Or I should say, women may save the day by choosing not to have big families. My only complaint is he doesn't look at the potential downsides of a declining and aging population - on market economies, tax bases, standards of living, etc.. and what conditions in the future could cause a reversal of increased birth rates, such as what happens during baby booms. Nothing is assured, but assuming the macro trends stay in place - globalization, urbanization, woman's liberation - the population problem, and conversely environmental and resource problems, may just have a good chance of resolving themselves with time, and we may look back on this period as an overpopulated transition to a more stable and gentle age.