When I hear the term “drunken monkey,” I first think of the Chinese martial art, a kind of Kung Fu. There’s also a surprising number of bars and restaurants called Drunken Monkey this or that. But in searching for information on beer in Saint Kitts and Nevis, the Caribbean island nation who celebrates their independence day today, I found an old news report that there are real drunken monkeys. In Beware of Alcoholic Monkeys on St. Kitts, they recount how these monkeys were “originally imported to the island by pirates, [and] were introduced to the tantalizing effects of umbrella-laden mojitos and shots of tequila by tourists a few decades ago. Not surprisingly, they developed a heavy hankering for it.”

A group of scientists from McGill University in Montreal, Canada, along with a foundation on the islands, saw an opportunity and captured 600 monkeys to study their drinking behavior. The monkeys drinking habits broke down into somewhat predictable groups:

• Social drinkers: the majority of the monkeys. They prefer alcohol diluted in fruit juice, will only drink in the company of other monkeys, and not before lunch.
• Regular drinkers: fifteen percent of the monkeys prefer their alcohol “neat” or diluted in water, not sweetened or diluted with fruit juice. Interestingly, steady drinkers do very well in social groups, and are good leaders. They run troops well, they keep order well, and they’re very dominant. This type of alcoholic monkey is a very functional animal.
• Binge drinkers: five percent of the monkeys drink their alcohol fast, get in fights, and drink themselves into a coma. Just as in humans, there are more young males in this group. If this group has unrestricted access to alcohol, they will drink themselves to death within 2-3 months. Binge drinkers differ from regular (or “steady”) drinkers by their drinking patterns rather than by the amounts of alcohol they consume.
• Teetotaler: fifteen percent of the monkeys prefer little or no alcohol.

So that breaks down like so:

• 65% = Social Drinkers
• 15% = Regular Drinkers
•  5% = Binge Drinkers
• 15% = Non-Drinkers

That looks similar to what I’d expect for people, too. Does anybody know how the same groups shake out for Americans, or humans across the world?

The UK’s Guardian summarized the results.

For many years, alcoholism in humans was thought to be purely a learned behaviour — the result of environmental factors. But more recent studies indicate that in humans, the tendency towards alcohol addiction has a genetic component: it tends to run in families. Research has found three regions on the human genome that may be linked to alcoholism. Unfortunately, since these areas contain up to 300 genes, it may be some years before specific “alcohol genes” are identified.

I think it is interesting that, despite living in a tropical paradise, without any economic problems or deprivation, this video clearly documents that some monkeys still become alcoholics. Additionally, this video shows how vervet monkeys’ alcohol use mirrors that of humans, suggesting that they too, have a genetic component. Further, human and vervet monkey DNA shares an 84.2% similarity. So even though it is difficult to study humans’ genetics and patterns of alcohol consumption, researchers can study vervet monkeys. So research is ongoing in these monkeys to better understand their patterns of alcohol use and abuse — valuable since scientists can carefully control the monkeys’ environment and the monkeys can be selectively bred so researchers can better understand the effects of particular genes on behaviour.

The study itself, Alcohol consumption in vervet monkeys: biological correlates and factor analysis of behavioral patterns, doesn’t reveal too much in the abstract, so I have to take the word of the two reports. But it certainly would be interesting to see if it does correlate to human behavior.