One thing I love about Cultural Evolution is how it makes us look at ordinary things we do every day from a completely new angle. As an example, if you think about it, wearing pants, especially in warmer climates, is a very strange thing. It turns that there is a surprising explanation why we do it (check my posts on The Evolution of Pants).
Similarly, some characteristics of our modern societies are actually a result of decisions made by our distant ancestors thousands of years ago. Take the domestication of plants—this was one of the most momentous decisions made by humans, which enabled cities and civilization, sciences and arts, modern government and warfare, and many other things, good and bad.
So much is well known. What is less known is that a choice of particular cultivar can have unexpected and profound consequences down the line.
Consider China. In the cooler and drier north the grains that were domesticated included first millet and later wheat. In the hot and humid south, the grain of choice became rice.
Wheat and rice require very different cultivation methods that actually shape societal institutions. Paddy rice cultivation requires massive labor inputs, which are, however, limited in time. Labor requirements are so high that a single family cannot do it. So what rice farmers do is that several families cooperate. They stagger planting times in such a way that they all first take care of one family’s farm, then go to the next, and so on.
Farmers planting rice. 2004. Photo: Brad Collis
Growing wheat, on the other hand, doesn’t require such collective effort. A family can take care of its farm by spreading the work over a longer period of time.
Different cultivars require different technologies to grow; not just agricultural, but also social technologies—institutions. And these institutions left a long-lasting imprint on people’s psychology. A recent study in Science by Thomas Talhelm and coworkers found that people from rice-growing counties were more interdependent, collectivist, and holistic thinking than people in wheat-growing counties. Note, experimental subjects tested by Talhelm et al were not farmers; they simply grew up in local societies whose institutions and even ways of processing information co-evolved with subsistence technologies in the past.
In the psychological test illustrated below, people from rice-growing regions chose holistic answers; those from wheat-growing regions chose analytical answers.
Measuring analytical versus holistic thinking. From Henrich, Joseph. 2014. Rice, Psychology, and Innovation. Science 344:593-594.
And this is not all. Rice versus wheat agriculture affects not only psychology, it affects health. That was literally a life-and-death decision that the early adopters of plant cultivars made for their descendants.
In an article that was published in the last issue of Cliodynamics: The Journal of Quantitative History and Cultural Evolution, Ned Kock, an economist at the Texas A&M University, analyzes the China II data on diet and mortality in 69 counties of China (between 1983 and 1993). Kock found that as the proportion of wheat in diet increased, so did mortality from vascular disease, such as heart attacks and stroke:
From Kock, Ned. 2015. Wheat flour versus rice consumption and vascular diseases: Evidence from the China Study II data. Cliodynamics 6: 130–146.
As diet shifts from completely rice-based to completely wheat-based, heart-disease mortality increases by 50 percent! That’s a huge effect.
A very interesting question, of course, is what it is about wheat that is so lethal. Because we have only correlational data (so far), any conclusions must be speculative. Ned Kock thinks that
it may not be wheat flour consumption that is the problem, but the culture associated with it, which is characterized by decreased levels of physical activity, decreased exposure to sunlight, increased consumption of processed foods, and increased social isolation. Wheat flour consumption may act as a proxy for the extent to which this culture is expressed in a population.
Note that “increased social isolation” is an aspect of more individualistic, and less collectivist culture of wheat regions. This could be a contributing factor.
Yet, readers of my blog would probably guess that, unlike Kock, I would place blame squarely on wheat. Simply put, wheat is a much more poisonous grain than rice. Especially if you consume polished white rice because most of the toxins that rice uses to deter herbivory are located in the brown skin of the rice grain. I have asked Paul Jaminet, the author of the Perfect Health Diet to comment on Ned’s article, and I hope this comment will be published in the next issue of Cliodynamics. So more is to follow.
maybe it’s the wheat, maybe it’s the liquor made from wheat. [or millet] in the north they make a white lightning which in modern times is a very potent super-liquor, perhaps in the range of 120 proof.
Perhaps, but I still think it’s the wheat itself… Eating wheat products was really one of the worst decisions humans made.
The Tallheim study has been sharply critiqued–I’ve read both the study and the critiques, and am probably as knowledgeable as anyone in this area, and I can’t really say for sure. More and better studies are needed. You certainly can’t tell from testing some students and such about long-term agricultural effects. My gut tells me they’re probably right, in a very broad sense, but we need more work.
Gene, in some ways the results are almost too good to be true. Such a beautiful example of cultural evolution. So yes, I hope that this study will be replicated and extended.
I think the article by Ruan, Xie and Zhang (2015) can be considered a thorough replication and it is largely negative and highlights a number of significant problems with the original paper. Of course it’s just one study, but I think, at very least, it means that the Talhelm et al. finding should be treated with due caution (especially when it supports desired outcomes).
Just to clarify, Talhelm doesn’t JUST suggest “people from rice-growing counties were more interdependent, collectivist, and holistic thinking” it also suggest that “people from rice provinces were more likely to reward an honest friend and less likely to punish a dishonest one—a sign of the in-group favoritism that pervades collectivist groups.”
Hence the issues with in and out group cooperation and varying levels of cooperation as Fukuyama elaborates in his book Trust.
That’s right, and fits with the macrohistorical pattern that China was always unified from the North. The cooperation characterizing southern Chinese is clearly very narrow based. Works well when you need to cooperate in a small group to work the fields, but not so great when you need to build an ultrasociety.
Rice-growing collectivists vs wheat-growing individualist is an intriguing argument – I think Malcolm Gladwell makes a similar argument in “Outliers”. Insofar as this effect is significant, how do you think its influence propagates throughout society beyond the agricultural sector?
More concretely, as economies develop on the basis of agricultural surplus, how does aforementioned effect enter adjacent/derivative occupations/industries such as merchandizing, transportation, handicrafts? How about into activities further-afield such as exploration and colonization of faraway/foreign lands (commercially or in populace)?
Tangentially, the relative collectivism of China as a whole has sometimes been attributed to its long history as a hydraulic empire, beginning perhaps with the semi-legendary Xia dynasty founded by Yu who was responsible for directing waterworks to deal with the Chinese version of the great flood. Is the argument that rice-growing societies are more collectivist than wheat-growing counterparts analogous to how hydraulic-works-dependent societies are more collectivist than societies not as dependent on large public works?
Gladwell’s main thesis, if I remember correctly, is that rice-growers have a stronger work ethic, not that they are more collectivist. Rice yields more calories per acre, but requires more backbreaking work than growing dry grains.
I think that if you look through Chinese history, the rice-growing regions did tend to generate more per capita wealth than the wheat/millet/sorghum North, which tended to be poorer.
Also, there are several threads to disentangle here: China has also been a giant cohesive empire for a longer period of time than almost anywhere else. I can’t think of another collection of regions that large that has been united together in one polity for such a long period of time (even when you take in to account the gaps).
It’s not really ancients deciding which cultivars to grow rather than climate dictating what grains to cultivate. Pretty much all the regions in China where the climate is wet enough (and warm enough) to grow rice do so. That’s because in terms of calories per acre, rice beats any other grain known to the ancient Chinese. The places that couldn’t cultivate rice grew other grains.
Also, the North unifying the South in China may have more to do with the fact that North China is one big plain (so easy to conquer and unify), after which the big empire in the North can pick off the various fiefdoms in the mountainous and riverine South (though note that the mountanous interior of Fujian wasn’t fully under central control until some 15 centuries or so after the first Qin empire).
Oh no, on the question of China’s geography yous should see this blog of mine:
I’d replied in that post as well.
So I suppose that I should modify what I said to “the North unifying the South in China may have more to do with the fact that North China is one big plain (so easy to conquer and unify) and for most of Chinese history (until the end of the Tang dynasty), the bulk of the Chinese population was in the North, so the North had force of numbers.
After the Tang fell, the Song unified from the North, the Yuan were Mongol invaders conquering southward, the Ming unified from the South, the Qing were Manchu invaders conquering southward, the Nationalists unified from the South, and the Communists were pan-Chinese (you can argue that their final offensive was from the north to the south, but the Long March actually originated in the South).
So that’s 2 invaders (and China’s neighbors to the north and northwest were always more dangerous to its survival than its neighbors to the south and southwest), 1 unifier from the North, 2 unifiers from the South, and 1 pan-Chinese unifier.