Ted Turner says that, to save the planet, the whole world needs a one-child policy. The human population is predicted to reach 10 billion by 2050—that’s pretty soon—and Ted doesn’t think the planet can take it. I did do a little slogging around on Google, and it seems the current expert consensus is on that number for Earth’s maximum occupancy. So is Ted right? Let’s look into it… First, let’s consider the world fertility rate. The fertility rate is basically an estimate of how many children each woman will have in her lifetime. The replacement rate is two (2), meaning if every woman had just two kids in her lifetime, the population would remain unchanged. A tiny bit of math tells you that a one-child policy is half the replacement rate, and would reduce population. So, I found some data on the fertility rates from the United Nations Population Division (graph mine). Total world fertility (children per woman) Actual and projected, 1950-2050 The world’s fertility rate is dropping...