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  • Writer's pictureLushmuddled

Drunken Monkeys

Updated: Jul 11, 2021

An Admittedly Incomplete History of Booze

I know, I know. We've all had that high school class where the teacher awkwardly talks about alcohol to underage kids. Alcohol is a social lubricant, it lowers your inhibitions, it can increase aggression yada yada. This is not what I'm talking about. Alcohol, in a social context, has been studied to death and there's not much I can add to that conversation. Anyone who knows me knows that I'm an historian; I believe that the reasons why we hairless apes joyfully imbibe a toxin has just as much to do to with evolution and history as it does social interaction.

In the beginning...

Not too appetising, really

At some point, we decided that we didn't want to live in the trees anymore. The problem is that we liked to eat fruit and fruit tends to grow in the tree tops. But, with a little bit of patience, the fruit would ripen and drop to the forest floors. This meant we could pick it up and eat it without having to climb. As anyone who has ever seen a fruit tree in the backyard or the wild would know, fallen fruit is usually somewhere on the spectrum between ripeness and rot - this means fermentation. Fruit in this state frequently contains 1% ethanol, but it can be as high as 8%.

This is called the Drunken Monkey Hypothesis.

Basically, we evolved to eat these fermented fruits. Ethanol at this level is a poison to most animals, causing the same effects as excessive drinking to us - dizziness, lethargy, nausea - but, about 10 million years ago, our primate ancestors evolved the ADH4 enzyme which meant alcohol could be converted into energy. Those drunken monkeys which could tolerate a higher ethanol content had the evolutionary advantage of being able to eat more of this fruit.

Nature's biggest lush - the pen-tailed tree shrew

We see this enzyme in humans, gorillas, bonobos and chimpanzees, which are all part of the same evolutionary branch. The aye-aye, a distant relative, evolved this independently on the island of Madagascar. The Malaysian pen tailed tree shrew puts us all to shame though. It is the only animal to have a higher tolerance for alcohol than humans and its diet consists entirely of fermented nectar. It drinks the equivalent of 10 glasses of wine every night and is, enviably, sober by morning.

So why did we evolve to tolerate alcohol? It's calorie dense. 7 calories per gram, it is an efficient source of energy for the mammal on the go. Only fat, at 9 calories per gram, has a higher concentration. Given that alcohol also stimulates the appetite (late night kebabs, anyone?), it also means that our ancient relatives were more likely to overeat, keeping them prepared long periods without food.

But the advantages for our distant ancestors don't stop there.

Image courtesy of Discover Magazine

What are the some socially disastrous affects of alcohol - increased aggression, decreased pain receptivity and decreased inhibitions (say no to drunk dialling!) - would have been very useful from an evolutionary viewpoint. Predators tend to attack when their prey is distracted by sleeping, drinking or eating. I don't know about you, but if I were a monkey, I would rather fight a sabre-toothed tiger while pleasantly buzzed, with 20 other drunk monkeys, rather than having to do it sober.

[PSA: Please don't get drunk with your friends and fight the wildlife. We don't live in caves anymore and sabre-tooth tigers are extinct. Even if you fight a lion, you'd all be arrested for killing an endangered animal. Just...don't. Okay?]

Fast forward...

You're not living in caves anymore, but a hut. You're not a monkey anymore either. In fact, you're a new species. You're human. But you still have those urges to consume alcohol, and it's still a good idea. Why?

This pot is 8000 years old and held 300L of wine

A lot of people forget that safe drinking water is a new thing (let's not start on lead piping). You can't just go to a river and drink. Cholera is a real possibility. Diarrhoea can cause fatal dehydration. Maybe an animal has defecated, or died, upstream now everything downstream is contaminated. This is why spring water was so precious to many ancient civilisations. It came from the ground and it was clean. But your local spring is running dry this time of year.

Hang on a second, you think, isn't there a harvest coming up? Isn't your body able to tolerate alcohol? What if, you excitedly tell your friends, what if instead of eating those grapes, we crushed them and fermented the juice?

And this is why humans began drinking beer and wine. Evidence from the Huan province in China suggests that we started making wine, deliberately, 9000 years ago. The oldest evidence of human building, Goblekli Tepe in Eastern Turkey, dates to 10 000 - 11 600 years ago and has evidence of beer production. The argument has been made that agriculture started because we wanted to make alcohol rather than bread. Not only is fermentation an effective way to preserve nutrients (think of making beer and wine like pickling fruits - alcohol is a natural preservative), it created a relatively safe drink. With only natural fermentation available, you'd still get drunk off the stuff, but it's likely that you'd see lower alcohol content across the board. Maybe around 8% - 12% for wine, and 3% to 5% for beer.

Mesopotamian seal c2600BC. Drinking beer with a straw

Ever wonder why there are so many booze-related deities, and not a lot to do with drinking water? That's your reason. The water could kill you. Beer, mead and wine was safe. It also gave you a really nice feeling which could only be divine. And, again, it's calorie dense. The Egyptian slaves were given beer as a meal, and they built pyramids on the stuff. It was a great drink for the pre-modern human - it slices, it dices, it even juliennes.

That's not to say that there aren't issues with alcohol consumption. I'm 33 years old. By history's standards, I'm lucky to be alive. I would have seen diseases, famines and war. The ancient Greeks would have called me an old man. It wasn't until the 1900s that the average life expectancy of the world began to creep past 30 years. The problems of long term alcohol consumption (heart disease, blood pressure, some cancers and, of course, cirrhosis) wouldn't have had time to properly take effect throughout history. The longer we live, the more careful we have to be with how we treat this toxin. Simply put, even in the 1800s, dysentry, plague or factory accidents were likely to get you long before anything alcohol related - unless you stumbled into the Thames or happened to insult someone much bigger than you while on the turps.

And now for something completely different...

Bar Brawl, by Anton Fischer, 1924

Like I mentioned above, alcohol can increase aggression in individuals. Humans are hardwired, throughout history and culture, to be able to maintain relationships with 150 - 250 different people. This, funnily enough, fits nicely with the average number of Facebook friends you're likely to have (check out Dunbar's Number if you're interested in this). We have bigger towns and cities and, while people still drink in communal areas, you're much less likely to exist within a community of just 150 - 250 people. Unlike the local bar 100 years ago where everyone knew everyone, we drink surrounded by many more strangers. Unless you're in a European town during soccer season where everyone is wearing their colours, the old world community with rival clans and family feuds doesn't really exist. It's simply not okay to slap someone with a glove and call for pistols at dawn, and the rollicking bar brawls you see in old Westerns and Errol Flynn movies are a thing of the past (and possibly Hollywood imagination).

Drinking alcohol is as much evolutionary as it is social. This is not to say that we need to drink alcohol. We don't. Not anymore. I'm lucky enough to have access to clean water and fresh juices. Much like meat, humans can easily survive without alcohol, but its role in our evolution is undeniable. The reality is that our circumstances are vastly different to those of our ancestors, human or simian. But we continue to drink and we continue to make merry. That glass of wine between friends has led to many a good conversation. Poems, stories, screenplays and blogs (especially this one) have seen the aid of a little liquid inspiration. Maybe there is something divine going on after all.

This is a light hearted look at alcohol consumption from a particular viewpoint. We may have evolved to drink alcohol, but excessive alcohol consumption has serious consequences. Please drink responsibly.

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