Fact-checking the zeitgeist
19 November 2013
By LUIGI GUARINO | Director of Science and Programs
We use 43 muscles to frown but only 17 to smile. 89.2% of all statistics are made up on the spot. You can probably think of examples. Numbers such as these have been repeated so often they have entered the zeitgeist. You know, the spirit of the age. I’m not sure if agricultural research and development can be said to have a zeitgeist, but even we have numbers like these. Rice, wheat and maize together provide more than 50% of all the calories we consume. 75% of global crop diversity has been lost in the past 100 years. These statements may even be true, but people have forgotten where they came from, and everyone sort of just takes it for granted that they are.
Well, almost everyone.
David Lobell, who is a professor in Environmental Earth System Science at Stanford University, has just published a post on the G-FEED blog on The future of crop demand. G-FEED stands for Global Food, Environment and Economic Dynamics, by the way, which summarizes its concerns rather well. The factoid David deconstructed in his post was that food demand will increase by 70% -- perhaps even double, according to some sources -- by 2050.
So, is the statement true? Or at least truer than the one about loss of diversity? Well, David doesn’t quite put it this way, but it depends on what you mean by food, demand, and increase. Read his post, it’s not that long, and very illuminating. I’ll still be here when you get back...
Ok, ok, here’s the short version. FAO originally calculated the now much-quoted 70%-more-food-demand-by-2050 figure, based on quite reasonable assumptions about global income and population growth. They have since revised it down to 60%, however, but only because they revised upward their estimates of production during the baseline year of 2006. And that 60% actually refers to a bundle of agricultural products weighted for price. Aggregate demand can go up even if demand for several commodities goes down, as long as demand for a very pricey commodity goes up. If you just look at cereals, the calculations actually predict a 46% increase in demand between 2006 and 2050.
So, how bad is that? David looked at historical trends, and it turns out that cereal production has actually been increasing pretty steadily at about the sort of rate that would result in a 50% increase by 2050. Basically, all we have to do is continue doing what we’ve been doing since 1960 and we’ll meet demand, for cereals at last. Phew.
Not so fast. There’s much less money going into agricultural research and extension. We have climate change to contend with, remember? And we don’t want to expand agriculture onto new land, do we? Plus agricultural inputs cost more every year? Not to mention that there’s evidence of cereal yields (rather than total production) have been plateauing of late. What David’s analysis in fact shows is that -- even worse than Alice’s Red Queen -- we will have to run faster than we have been just to keep pace with demand for cereals.
No, we probably won't have to double production by 2050. But a 50% increase is plenty difficult enough to achieve. It certainly cannot be taken for granted, any more than David took for granted that the number is accurate in the first place. It means breeders will have to work faster and smarter, using all the tools at their disposal. And they will need all the diversity they can get their hands on. That’s the raw material of crop improvement, and it’s found in the world’s genebanks. Which is something else that I hope the zeitgeist won’t take for granted for much longer.