Of all the blogs that fill the universe, Andrew Revkin’s New York Times Dot Earth is arguably the most important. While the rest of us fret endlessly over matters like whether or not abortion is murder, or what to do about global warming (at least most scientifically-informed people finally agree that it’s happening), or whether the burqa ought to be banned in France, or whether the painter Francis Bacon is great or not (most of these topics have been subject to my own public ruminations), Revkin calmly reports on what’s going on with our planet Earth. Probably the most disturbing news he’s delivered of late is news that hardly made the news at all: By 2050, the population of the world is expected to reach 9 billion people.

To help us feel what this means, and not merely casually spit it out as a cocktail party statistic, Revkin tells us that this is “essentially adding two Chinas to the number of people alive today.” Ponder that one.

According to Dot Earth, we now have a billion hungry people (yes, many of them residing right here in the good old overweight United States of America). That’s one sixth of the world’s population, and an all-time high number of hungry people—probably due at least in part to the current economic crisis.

When I was in college, students and faculty talked endlessly about the population explosion. Had there been blogging then, it would have been the stuff of blogs as well. In particular, everyone talked about Paul R. Erlich’s best-selling book, Population Bomb (1968). A lot of us who were young college students from the middle class, responding to the suggestion at the time that middle-class and rich people consumed vastly more of the world’s resources than poor people, vowed to never do what our parents’ generation had done. We rejected the 4- and 5-child family post-War model in favor of pill-controlled one- or two-kid families.

Today, what with fertility drugs, endless articles about baby-bumped celebrities, the popularity of Octomom and Angelina Jolie, and a plethora of TV shows dedicated to celebrating the “reality” of raising sextets, or (I love this one) being an unmarried, sixteen-year-old pregnant high school student living happily with her parents, it’s hard to fathom what’s going on in our culture. Apparently, we’re back in the pre-modern era, or on some farm, where reproductive capacity for its own sake is a valued commodity.

Because of some errors in calculation, not to mention the Pill and advances in food production (many of the latter accompanied by severe strains on the environment), Erlich’s dire Malthusian-inspired predictions that the world would suffer devastating famines in the 70s and 80s did not happen. Yet the underlying thesis is a matter of principle, rather than empirical data, and the truth still holds that there’s a limit to how many human beings this world can support. Few would dispute that nine billion will take us up to, if not over, that limit.

Ordinarily, I like to crack jokes in the face of really bad news that’s out of our individual control, but for the life of me I can’t think of a single joke to make about the population explosion. Bill Bryson’s A Short History of Nearly Everything (2005) was chock full of terrible stories of impending catastrophe—such as how the universe will end in a fiery ball, or, on the smaller, gentler side, how the sun will die, or on the really sweet side, how Yellowstone’s volcano, which hasn’t blown in 70,000 years, is now long overdue for a really big blow.

My husband and friends and I all had rip-roaring fun talking about how we’d handle our swan dive into a Black Hole, or catch the final rays from the dying sun. As for Yellowstone, when it finally blows, Bryson says it’ll wipe out just about everything between Wyoming and New York. I think he said something like “smothered in ash” to describe what would happen to Manhattan, but I myself thought it was cuter to say, “covered with a little dust.”

But back to the population explosion. Can policy-makers possibly lower this 9 billion figure? From my non-wonk vantage point, the best hope seems to lie in empowering women. Historically, whenever women taste life freed from endless childbearing and husband-pleasing, they generally choose smaller families.

On the home front, here in America, I fervently hope that educated people do not return to blithely having large families. As individuals, we may not be able to do much about the population explosion. That requires concerted government policies, and even then we seem to be in mighty big trouble.

Yet as individuals, we remain responsible for how we lead our lives. Surely that includes how large we choose to make our families.