SPEAKER_02: Amazing, fascinating stories of inventions, ideas and innovations. Yes, this is the podcast about the things that have helped to shape our lives. Podcasts from the BBC World Service are supported by advertising.
SPEAKER_01: 50 things that made the modern economy with Tim Harford.
SPEAKER_00: In the early 1900s, newlyweds Kathy and Cappy Jones left Connecticut to start a new life as farmers in northwest Mexico's Yaqui Valley. It was a little-known place, a few hundred kilometres south of the border with Arizona. Dry, dusty and largely destitute. But for the Joneses, it became home. They raised two daughters. When Cappy died in 1931, Kathy decided to stay on. Just down the road, the state's ambitious governor set up an agricultural research centre, the Yaqui Valley Experiment Station. Impressive stone pillars went up at the entrance, irrigation canals were dug. For a while, the centre raised cattle, sheep and pigs. It grew oranges, figs and grapefruit. And then it fell into disuse. By 1945, the fields were overgrown, the fences fallen, the buildings windows shattered and roof tiles missing. The place was infested with rats. But then Kathy heard strange rumours. Some crazy gringo had set up camp in this dilapidated place, despite the lack of electricity or sanitation or running water. And he hadn't brought machinery. He'd been digging with a hoe. Kathy drove over to investigate. She learned that the young man was from Iowa and he was working for the Rockefeller Foundation, trying to breed wheat that could resist stem rust, a disease that had ruined many a crop. Further south, where he was supposed to be based, you had to sow in spring and harvest in autumn. Up here with a different climate, you could sow in autumn and harvest in spring. By relocating for a few months, perhaps he could find varieties of wheat that would grow in diverse conditions and do his experiments twice as quickly. But there was a problem. Mexico's government stipulated which regions the Rockefeller Foundation could work in, and this wasn't one of them. His bosses told him he could go if he wanted, but they couldn't pay for a tractor or to make the place habitable. Officially they'd know nothing about it. Kathy took pity on the determined young Iowan. He later admitted he couldn't have survived without Mrs Jones. She invited him round for weekly meals and to have a bath and to wash his clothes. She taught him Spanish and she drove him into the nearest town to do his shopping. Twenty-three years later, the main street of that town was renamed in his honour, Calle de Dr Norman E Borlaug. That same year, in 1968, Stanford biologist Paul Ehrlich published an explosive book. In The Population Bomb, Ehrlich noted that in poor countries such as India and Pakistan, populations were growing more quickly than food supplies. In the 1970s, he predicted, hundreds of millions of people are going to starve to death. Thankfully, Ehrlich was wrong because he didn't know what Norman Borlaug had been doing. The crazy gringo later got a Nobel Prize for the years he spent shuttling between Mexico City and the Yaqui Valley, growing thousands upon thousands of kinds of wheat and carefully noting their traits. This kind resisted one type of stem rust but not another, this kind produced good yields but made bad bread and so on. He couldn't sequence the wheat's DNA to figure out which genes caused which traits. That technology was decades away. The best Borlaug could do was cross the varieties that had some good traits and hope that one of the crossbreeds would happen to have all the good traits and none of the bad. It was painstaking work but eventually it paid off. Borlaug produced new kinds of dwarf wheat that resisted rust, yielded well and crucially had short stems so they didn't topple over in the wind. Through further tests, he worked out how to maximise their yield, how far apart to plant them, how deep with how much fertiliser and how much to irrigate. By the 1960s Borlaug was travelling the world to spread the news. It wasn't easy, many couldn't conceive that another way was possible. But eventually developing countries started to import Borlaug's seeds and his methods and from 1960 to 2000 their wheat yields trebled. Similar work followed on corn and rice. It was dubbed the Green Revolution. Ehrlich had predicted mass starvation. In fact the world's population more than doubled. And yet worries about overpopulation never entirely go away. Perhaps that's to be expected. It's one of the oldest questions in economics dating back to the world's first professor of political economy, Thomas Robert Malthus. In 1798 Malthus published an essay on the principle of population. It made a simple argument, populations increase exponentially. Two, four, eight, sixteen, thirty-two. Food production doesn't. Sooner or later there are bound to be more people than food with consequences that won't be pleasant. Happily for us it turned out that Malthus had underestimated how as people get richer they tend to want fewer children so populations grow more slowly. Malthus also underestimated Norman Borlaug. Over the years human ingenuity has meant food yields have kept pace. At least so far. But while population growth has slowed the UN projects will add another few billion people before the century's end. By one reckoning food yields need to keep rising at 2.4% a year. And they're not. Progress has slowed and problems are mounting up. Climate change, water shortages, pollution from fertilisers and pesticides. These are problems the Green Revolution itself has made worse. Some say it even perpetuated the poverty that keeps the population growing. Fertilisers and irrigation cost money which many peasant farmers lack. Paul Ehrlich, now in his eighties, maintains he wasn't so much wrong as ahead of his time. Perhaps if Malthus were still alive in his two hundred and fifties he'd say the same. As one expert put it to the author Charles Mann, the breeders have been pulling rabbits out of their hats for fifty years. They're starting to run out of rabbits. Or are they? Since genetic modification became possible it's mostly been about resistance to diseases, insects and herbicides. And while that does increase yields it hasn't been the direct aim. That's starting to change. And agronomists are only just beginning to explore the gene editing tool CRISPR which can do what Norman Borlaug did much more quickly. As for Borlaug, he saw that his work had caused problems that weren't handled well. But asked a simple question. Would you rather have imperfect ways to grow more food or let people starve? It's a question we may have to keep asking in the decades to come. For more on Norman Borlaug see Our Daily Bread
SPEAKER_01: the essential Norman Borlaug by Noel Wietmayer. For a full list of our sources please see bbcworldservice.com slash 50 things.