With our species’ long history of creating alcoholic beverages, it is easy to forget that alcohol occurs in nature too. All kinds of wild animals routinely consume alcohol, including non-human apes, birds, and flies. The western honeybee has even emerged as a model species for studying the effects of alcohol consumption.
Honeybees consume alcohol when wild yeast grows in flower nectar. The yeast in nectar produces ethanol through fermentation in the same way that brewers’ yeast produces ethanol in beer. In the lab, honeybees will readily drink sugar water spiked with alcohol, which mimics this yeasty nectar. Using this method, scientists have shown that honeybees can get intoxicated and eventually build up a tolerance when they drink alcohol regularly.
Although alcohol use disorder in humans is driven by a complex set of biological and social factors, studying honeybees may help us understand some of the fundamental physiological processes underlying it. With this goal in mind, a research team in Poland ran an experiment to see if honeybees showed one of the key features of alcohol addiction: withdrawal.
In their recently published study, the researchers fed half of the bees sugar water with ethanol, and the other half without ethanol, for three weeks. After that, half of the bees in each group were switched to the opposite diet for three days. The researchers then tested how eager the bees were to drink alcohol-spiked sugar water.
The bees that had never encountered alcohol before consumed the least of it, while the bees that had been cut off after three weeks of alcohol-drinking consumed the most. These bees drank more alcohol than any of the other groups, including those that had consumed alcohol continuously throughout the experiment.
The researchers concluded that honeybees show signs of alcohol withdrawal after just a few days of deprivation. Of course, more research is needed to fully understand the basis of the bees’ behavior and what it means for alcohol studies more broadly. But it is evident that at least some of alcohol’s impacts on animal behavior are more widespread than we once believed.