Yale Environment 360: Until just a couple weeks ago, the great global food challenge was how to feed 9 billion people in 2050. But no longer -- the number of mid-century mouths just jumped. Now its projected to be 9.6 billion, closing in on double-digit billions. And forget about expectations that world population will stabilize this century: By 2100, according to the latest projections, the number of people on the planet will hit 10.9 billion -- and will still be growing by 10 million a year. These hundreds of millions...