A Sip for the Ancestors: The True Story of Civilization’s Stumbling Debt to Beer and Fungus

[1]? With agriculture came settlements, kings, waterworks, social classes, complex buildings, politics, writing, recorded history and the iPad. All of this came with a startling inevitability. Similar trajectories unfolded independently around the world^. Nothing could be more straightforward than making a hole in which to put a seed. You push your fingers into the Earth. You take the seed. You drop it in and cover it and pull the weeds. What has grown is unfathomably complex. It is a modern world held aloft by the leaves, or more literally the descendants of that first farmed plant. The question is why we planted that seed, and whether it could really have anything to do with beer.

Today, you, like most humans, depend on agriculture. The atoms in your body come from relatively few crops. Essentially none of your atoms are derived from wild plants or animals. If you were born in the U.S., more than half of your body may be composed of atoms derived originally from corn. We tend to see agriculture as an invention for which we have failed to record the inventor, akin to the telephone or the cotton gin. Somewhere far enough back in time there is, in this telling, a Henry Ford of the wheat seed. But maybe it makes more sense to assume agriculture would and could be invented, but to ask, why? Agriculture led to progress, but also sorrow. Lifespans shortened and a range of health metrics, such as height, bone density and pathology, worsened.  Class structures developed. The poor and rich came into existence. Why would any society choose the path to a harder life? Katz thinks the answer is beer.

The first beers would have been accidental. A mash of wild wheat and sprouted barley was left out, in a clay pot, on a clay shelf, in among the mud. Perhaps yeast fell in and fermentation began. The same is true of the average backyard. Someone drank the result (we have all known someone who would) and thought it worth making more. They would have used whatever yeast fell down out of the sky. Yeast is everywhere; in our studies of homes the average living room is host to more than a dozen kinds of yeasts. Put food out and yeast will fall in. Yeasts are single-celled fungi. They eat simple sugars. As they do, they produce more complex compounds and alcohol. The first beer would not have been high in alcohol content. But, if someone drank enough, they would have started to feel the party coming on [2].

Beer and bad decisions are no strangers. You have your examples. I have mine. The city of Raleigh, where I live, was founded when a local landholder, over too many beers, convinced government officials to buy his land to build a city. The land, it would later become clear, was no good for farming, far from rivers and oceans and otherwise a humble place to begin (out of which a lovely city has nonetheless grown). The first bad decision beer led to though might have been agriculture.

By the time agriculture became a possibility, people would have been living in densities greater than any experienced before by a primate. They were densities sufficient to cause social problems-a kind of proto-urban pathological strife. Beer and other intoxicants might have quelled some of these problems. “Dude, I’m sorry man, I did not mean that about your mom. Have you tasted my fermented wheat? Its all cool.” Beer also had other things to offer. Thanks to yeast, beer has more of several key nutrients, such as the B vitamins, than do the seeds out of which it is made. Beer also allowed food to be stored, as beer. And then there is disease…

Epidemiologists refer to the emergence of diseases associated with settlement as the first epidemiological transition. Beer might have made this transition more bearable. As Katz put it, “beer drinkers would have had a ‘selective advantage’ in the form of improved health for themselves and ultimately for their offspring.” But even as beer might have saved us, it asked something in return. To make enough beer to satisfy early demand we had to begin to farm. Wheat and barley, Katz imagines, were domesticated in order to produce beer and then, only as an afterthought, food. [3] What Katz envisions, as he put it in an interview with the New York Times several years ago, is that “the initial discovery of a stable way to produce alcohol provided enormous motivation for continuing to go out and collect these seeds and try to get them to do better.”

That beer has nutritional value absent from wheat and barley is indisputable, as is the observation that beer makes us feel good (at least initially). But, let’s return to the issue of disease. Katz did not dwell on disease, but disease definitely dwelled in the pre-agricultural settlements in which civilization began. High densities of people lead to more opportunities for diseases to pass body to body. The greatest challenge in being a parasite, whether a worm, bacteria or virus is getting from one host to another. When hosts are rare and far apart, a parasite has trouble finding them. Imagine having to find a single rare species out in the Amazon or the Serengeti. The task is harder still if, as is the case for many parasites, you are unable to walk or fly. Many parasites depend instead on riding the wind, the water or the hairy body of a mosquito. If you are a parasite that lives by such chance, most of your children will die and so you make many children and favor common hosts, like settled humans.

As humans began to build permanent homes and stopped migrating seasonally, large groups the odds a good wind, a river’s flow or a mosquito’s flight, would take a pathogen from one human to another increased, dramatically. As those odds increased, not only did many parasites and pathogens evolve the ability to “use” humans, many switched to using humans exclusively.

Nearly all water borne diseases of humans evolved after humans settled; these diseases enter the water when we poop and then colonize other humans when they drink the resulting contaminated water. Once humans began to live in permanent or semi-permanent settlements the presence of both humans and human feces in water was a near inevitability (as it remains in many parts of the world), an inevitably that allowed water borne diseases to succeed. Perhaps it was in this context that the need for agriculture arose, at least in the fertile, crescent. Beer makes you feel good, has nutritional value AND might kill pathogens and so drinking beer and other fermented beverages would save lives from diseases like typhoid and cholera by preventing them from being passed from one person to the next. Beer was the last wall of defense between life and death.

The first alcoholic beverages were low in alcohol content. High alcohol content drinks depend on alcohol tolerant yeasts that appear to have evolved only after many generations of beer and eventually wine brewing. The first beer was light on both buzz and taste. You might add some honey or dates. It would then taste better, but not good, not compared with foods that could be gathered, foods like figs, berries and wild meat [4]. The first beers were not the garden’s delicious fruits but instead its bitter, medicine.

Katz offered his beer before agriculture hypothesis early in his career but struggled to think of how it might be tested. Of course, he could look at the archaeological evidence, which he did. He predicted that the evidence for making beer should find pre-date that for making bread. It appears to. He also predicted settlements would be discovered from the time before agriculture, large settlements; they have been. But this wasn’t enough. Few scientists followed up on Katz’s idea and he drifted off into other studies. It lay fallow, at once interesting and untended. Science can be beautiful, powerful and elegant. It can also be frustrating. Ideas can wait generations to find their moment. Sometimes good, right, true and elegant ideas never find their time. They sit like seeds, expecting light that might not come. Katz’s idea seemed as though it might become one of those ideas. Then, just last year a group, led by Todd Schlenke at Emory University, working on, of all things, fruit flies, made a major discovery. Schlenke and his students did not know about the work of Katz, but what they did know was how to test whether animals drink booze to kill their pathogens.

Header photo: Saccharomyces cerevisiae cells in DIC microscopy, Masur | Wikimedia Commons