The UN's new population forecast for the world has some eye-popping figures, especially about Africa in general and Nigeria in particular

Its charts show that Nigeria, about the size of Texas, will surpass the entire United States in population by 2050. By 2100, it is expected to have an astonishing 1 billion people and be poised to overtake China. (The latter country will be shrinking and likely headed for a demographic nightmare.) As for the African continent, it will see a population explosion nearly unprecedented in human history. The biggest nation in 2100, however, is expected to be India, with a population somewhere around 1.5 billion. But its growth will level off around 2065 — meaning Nigeria looks on track to be No. 1 in the subsequent decades. As for the United States, its growth will rise slowly but steadily over the century and should be around 500 million by 2100. The world's overall population, now at 7.2 billion, is expected to be at 11 billion by then.