Life as a pen-tailed tree shrew in the tropical forest can seem like a party. The pen-tailed tree shrew is the first non-human mammal known to display alcoholic behavior. As these cute little creature feed on fermented bertam palm nectar without ever getting “drunk”.

The bertam palm plant flowers nearly year-around in the rain forest, so they make perfect food source. The tree shrew spend about two hours per night drinking up the nectar. A nectar with 3.8% alcohol content, much like beer.

Pen-tailed tree shrew are native to the tropical rain forest of Southeast Asia. They look a bit like squirrels and are about the same size.

This little tree shrew looks more like a bat or mouse with an unusual tail.  The tail looks more like wheat then than a pen… maybe an old fashioned pen.  Those tiny fingers and toes are really good at gripping the branch too.  Photo from National Geographic.

Frank Wiens, a biologist at the University of Bayreuth (Germany) checked to see the animals’ alcohol consumption by testing hair samples for ethyl glucuronide.

Wiens found that the tree shrews consume alcohol at rates that would be dangerous to most mammals. It seem their body is able to metabolize the alcohol differently then humans and do no get drunk from these nightly nectar.

Wiens also adds that the palm flower also benefits from the tree shrew too. And if alcohol production appears critical to the palms’ reproduction because it entices tree shrews to pollinate their flowers. So Wiens wonder, “If alcohol is crucial for an ecological relationship [like the pollinator relationship], then it should also exert some sort of beneficial effect to the animals and we can only speculate on those effects.”

Looks more like a mouse in this illustration.  From Wikipedia.

Palm wine is also a common beverage that is obtained from the tapping of the cut flower of the palm tree.  Due to the natural yeasts in the air, palm sap begins fermenting immediately after collection.  Within a few hours, the fermentation yields sweet palm wine of up to 4% alcohol content.

“Palm trees are all different. Some take 30 days to fill a two-litre bottle, others will take just a week. But I know my trees very well, so I know when the bottle will be full. I used to use gourds but birds make holes in them, so now I often use old plastic water bottles. It used to rain much more than now and the trees would produce more wine.” - Photo from BBC News

Palm tapping is a career for many people in southern Senegal. Some say it’s better then growing peanuts or rice.

But the pen-tailed tree shrew just tap the nectar as fun survival activity.