Alcohol is not the sole preserve of humans. Researchers from the University of Exeter have revealed that ethanol consumption is quite widespread in the animal kingdom. From jungles to orchards and tropical islands, many wild species regularly indulge in the pleasures of natural fermentation. “ We are moving beyond the idea that alcohol is a substance solely linked to human activity. In reality, ethanol is widely present in nature » explains researcher Anna Bowland, who participated in this research.
A drunken feast millions of years old
The appearance of flowering plants marked the beginning of a heady era in natural history. Their fruits and sweet nectars, once fermented by yeast, produce ethanol at varying concentrations. While most fruits contain between 1% and 2% alcohol, some, like palm fruits, can reach cocktail-worthy levels of up to 10%. In this natural open-air bar, there is no shortage of guests !
Scientists have captured astonishing scenes in Guinea: chimpanzees (Pan troglodytes verus) greedily drinking fermented palm sap. In Panama, spider monkeys (Ateles geoffroyi) do not shy away from their pleasure in front of the fruits of the Mombin Plum, a local tropical tree. The latter, with a tangy taste and pleasant smell, are full of nectar containing up to 2.5% alcohol. These distant cousins of man seem to have developed, like us, a certain taste for fermented drinks.
When animals lose control
As for us, alcohol abuse, for certain animals, does not necessarily succeed. While some species manage their alcohol consumption remarkably well, others end up in trouble from time to time. Cedar Waxwings (Bombycilla cedrorum), a species of American passerine, sometimes have the painful experience: after having gorged themselves on overripe Brazilian pepper berries, these birds can end their flight against fences, victims of fatal drunkenness.
Very surprisingly, it is on the side of insects that the negative effects of alcohol can be verified more easily. Certain species of fruit flies or fruit flies bear the brunt, and alcohol has a negative influence on their reproductive behaviors. Male fruit flies drown their sorrows in ethanol after a refusal from a female, while the latter become less selective in their choice of partners after a few sips. A behavior that can appear to be very close to ours, even though we are still very far from these species from an evolutionary point of view.
Only one species seems to tolerate alcohol ingestion very well: the oriental hornet (Vespa orientalis), a species of hornet native to the Middle East and North Africa, whose populations have extended to the south of France, particularly Marseille. These insects are capable of ingesting solutions containing up to 80% alcohol without suffering the slightest harmful effect. It is a study from Tel Aviv University which recently highlighted this exceptional tolerance.
Ethanol consumption in certain animals is therefore not a simple question of food availability. In some cases, it is well linked to adaptations to particular environments (tropical regions where fruits ferment quickly) and would play an important role in social interactions. It was Boris Vian who said: “ Man is the only animal that agrees to die as long as he derives pleasure from it (drugs, alcohol, etc.)” ; modern science would therefore have proven him wrong ?
- Researchers have discovered that ethanol consumption is common in the animal kingdom, by observing animals drinking naturally fermented liquids.
- Some species, such as monkeys and birds, show signs of drunkenness, and for some, excessive drinking can even be fatal.
- The oriental hornet, on the other hand, is distinguished by its exceptional tolerance to alcohol, being able to ingest solutions containing up to 80% alcohol without problem.
