Trophic level as a measure of economic development?

I will return this this new Nature article in another post, since it brings up a lot of interesting points, but I think this ancillary point was worth highlighting (even though the authors don't make this case): Looking at where humans sit in the food chain might be a useful (or at least interesting) measure of economic development.  In rich countries, land is used to feed animals that we eat.  In poor countries, people eat a higher fraction of crops themselves.  We've known about this phenomenon for a while now, but this map from the paper is striking because of its fully global perspective:

Here we show the fraction of the world’s total cropland that is dedicated to growing food crops (crops that are directly consumed by people) versus all other crop uses, including animal feed, fibre, bioenergy crops and other products. Averaged across the globe, 62% of total crop production (on a mass basis) is allocated to human food, 35% for animal feed (which produces human food indirectly, and less efficiently, as meat and dairy products) and 3% for bioenergy crops, seed, and other industrial products. There are striking disparities between regions that primarily grow crops for human consumption (such as Africa, South Asia, East Asia), and those that mainly produce crops for other uses (such as North America, Europe, Australia).
Copyright: Nature


  1. Is this true at a micro-level? Are vegans economically worse off than omnivores?

  2. I don't think this applies to voluntary vegans. But people who are too poor to purchase animal food products may be involuntary vegans are a different story.  This famous paper by Jensen and Miller shows that as people become poorer (due to changes in prices), they eat more grains and less meat.