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The Beetles That Cannot Get Enough Alcohol

The Beetles That Cannot Get Enough Alcohol

Insects demonstrate a variety of seemingly strange behaviors that have yet to be explained by scientists. For example, it has long been known that ambrosia beetles are attracted to alcohol. One entomologist has commented on the beetles he has found within his beer mugs in the past. In fact, ambrosia beetles are a common sight around German beer halls. Ambrosia beetles have also been found boring through coffins in order to access the ethanol secreted by dead bodies. These beetles are considered serious tree pests in their native southeast Asia, as well as Europe and the United States. When trees become stressed as a result of environmental disasters, like floods, they secrete ethanol (alcohol). Naturally, scientists initially assumed that ambrosia beetles targeted stressed trees by sensing the alcohol that trees secrete. This would explain their attraction to alcohol. However, a group of researchers have shed some doubt on this hypothesis after conducting their own study into the odd beetle behavior.

Ambrosia beetles are fungus-farming insects, and they use trees for this purpose. Since alcohol kills microbes and fungi, researchers have wondered why these beetles prefer to cultivate fungus in alcohol-rich trees. Obviously, alcohol poses a threat to the fungi that the beetles cultivate. Therefore, it has been suggested that alcohol benefits ambrosia beetles in another unknown way. In order to explain the ambrosia beetles attraction to alcohol soaked trees, a team of researchers subjected the beetles to an experiment.

The study showed that alcohol influences which types of plants and fungi grow on trees. Beetles that inhabited stressed trees ended up cultivating better and more plentiful yields of symbiotic fungi. In other words, the alcohol promoted the growth of symbiotic fungus while also killing undesirable plant growth, like weeds. Fungus farms are often attacked by weed-like forms of vegetation, which can be disastrous for the insects involved. However, trees saturated in alcohol worked to protect fungus farms from these harmful weeds. Naturally, ambrosia beetles that choose sufficiently alcohol soaked trees thrive in the wild.

Do you believe that fungus-farming termites are also attracted to alcohol soaked trees for the same reason that ambrosia beetles are?