What do you believe is the single most important factor driving up the cost of living in Nigeria?

Right now, human population growth is doing something long thought impossible—it's wavering. It's now possible global population could peak much earlier than expected, topping 10 billion in the 2060s. Then, it would begin to fall.

In wealthier countries, it's already happening. Japan's population is falling sharply, with a net loss of 100 people every hour. In Europe, America and East Asia, fertility rates have fallen sharply. Many middle or lower income countries are about to drop too.

This is an extraordinary change. It was only 10 years ago demographers were forecasting our numbers could reach as high as 12.3 billion, up from around 8 billion today.

For 50 years, some environmentalists have tried to save the environment by cutting global population growth. In 1968, The Population Bomb forecast massive famines and called for large-scale birth control.

Now we face a very different reality—population growth is slowing without population control, and wealthy country populations are falling, triggering frantic but largely ineffective efforts to encourage more children. What might a falling global population mean for the environment?

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