Excerpts from Slate Mag:
‘Moreover, the poor, highly fertile countries that once churned out immigrants by the boatload are now experiencing birthrate declines of their own’
Why is this happening? Scientists who study population dynamics point to a phenomenon called “demographic transition.”
“For hundreds of thousands of years,” explains Warren Sanderson, a professor of economics at Stony Brook University, “in order for humanity to survive things like epidemics and wars and famine, birthrates had to be very high.” Eventually, thanks to technology, death rates started to fall in Europe and in North America, and the population size soared. In time, though, birthrates fell as well, and the population leveled out. The same pattern has repeated in countries around the world. Demographic transition, Sanderson says, “is a shift between two very different long-run states: from high death rates and high birthrates to low death rates and low birthrates.” Not only is the pattern well-documented, it’s well under way: Already, more than half the world’s population is reproducing at below the replacement rate.
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If the Germany of today is the rest of the world tomorrow, then the future is going to look a lot different than we thought. Instead of skyrocketing toward uncountable Malthusian multitudes, researchers at Austria’s International Institute for Applied Systems Analysis foresee the global population maxing out at 9 billion some time around 2070. On the bright side, the long-dreaded resource shortage may turn out not to be a problem at all. On the not-so-bright side, the demographic shift toward more retirees and fewer workers could throw the rest of the world into the kind of interminable economic stagnation thatJapan is experiencing right now.
And in the long term—on the order of centuries—we could be looking at the literal extinction of humanity.
That might sound like an outrageous claim, but it comes down to simple math. According to a 2008 IIASA report, if the world stabilizes at a total fertility rate of 1.5—where Europe is today—then by 2200 the global population will fall to half of what it is today. By 2300, it’ll barely scratch 1 billion. (The authors of the report tell me that in the years since the initial publication, some details have changed—Europe’s population is falling faster than was previously anticipated, while Africa’s birthrate is declining more slowly—but the overall outlook is the same.) Extend the trend line, and within a few dozen generations you’re talking about a global population small enough to fit in a nursing home.