Bumblebees Self-Medicate with Quercetin to Fight Fungal Infections 2026

Bumblebees self-medicate with quercetin, a plant compound, when infected by a specific fungal pathogen, according to a study by researchers at the Universities of Leuven and Valladolid. This finding adds to growing evidence that animals can tailor their medication to the specific disease they face.

Humans are often considered the most prolific self-medicating animals, but many species use plants to treat illnesses or disinfect wounds. The new research shows that bumblebees (Bombus terrestris) can go further: they appear to detect which medication they need for a given infection.

Study reveals bumblebees self-medicate with quercetin for fungal infections

The scientists observed 18 bumblebee colonies placed in a flight chamber and divided them into three groups over two weeks. One group was exposed to the fungus Ascosphaera apis, another was infected with the bacterium Serratia marcescens, and a third was fed sterile pollen and sugar water without pathogens.

The chamber contained eight robotic flowers capable of releasing specific substances. The researchers found that bumblebees infected with the fungus sought out quercetin, while those infected with the bacterium did not show the same preference. This indicates that the bees can distinguish between infections and choose the appropriate treatment.

How the experiment worked

The robotic flowers allowed the researchers to control the availability of quercetin and observe the bees' behavior. The bees exposed to the fungus consumed more quercetin than those in the other groups, suggesting a targeted response to the fungal infection.

This is not the first example of self-medication in insects. Previous studies have shown that ants and fruit flies can also use plant compounds to combat infections. However, the ability to select the right substance for a specific pathogen is a more sophisticated behavior.

Why this matters for bee health and agriculture

Bumblebees are important pollinators for many crops and wild plants. Fungal infections like those caused by Ascosphaera apis can weaken colonies and reduce pollination services. Understanding how bees combat diseases naturally could help beekeepers and farmers support healthier populations.

The study also raises questions about how bees detect pathogens and decide which plant compounds to seek. The researchers suggest that the bees may use chemical cues from the infection or learn from previous experiences.

• Bumblebees infected with a specific fungus consume more quercetin, a plant compound with antifungal properties.
• They do not show the same behavior when infected with a bacterium, indicating pathogen-specific self-medication.
• The study used robotic flowers to control the availability of quercetin and observe bee behavior.
• This behavior adds to evidence that insects can tailor their medication to the disease.
• Understanding self-medication could inform strategies to support pollinator health.

What the researchers found

The team from Leuven and Valladolid monitored the bees' consumption of quercetin and other substances. They found that fungus-infected bees had a higher intake of quercetin compared to the other groups. This increased consumption was not seen in bacteria-infected bees or in the control group.

The researchers also noted that the bees did not simply increase their intake of all substances when infected; they specifically targeted quercetin. This suggests a level of specificity in their self-medication behavior.

Implications for understanding animal self-medication

This study adds to a growing body of research on animal self-medication. From primates eating medicinal plants to birds selecting specific leaves for nest building, many animals use natural substances to improve their health.

The bumblebee study is notable because it demonstrates that even insects with small brains can perform complex behaviors: detecting a pathogen, choosing an appropriate treatment, and adjusting their behavior accordingly. This challenges the idea that self-medication requires advanced cognition.

Future research could explore how bees learn to associate specific plant compounds with recovery from illness. It could also investigate whether other pollinators exhibit similar behaviors. The background to this story is set out in Moscardón Bumblebee: Giant Patagonian Pollinator Faces Extinction. A related thread runs through Energy Utilities: latest articles. Earlier coverage in Japan's Stray Cat Invasive Species Plan Sparks Backlash shows how the argument developed.

What to watch next

As researchers continue to study self-medication in animals, we may discover more examples of targeted medication use. For bumblebees, understanding how they combat diseases could lead to better ways to protect colonies from infections. A closer look at the same subject appears in Dolphin Forces Prey to Vomit: A New Form of Cleptoparasitism. Anyone following the wider picture can start with Saltwater Crocodiles Surf Ocean Currents to Travel 590 Kilometers. The same theme surfaces in The 1945 Superdog Experiment: 500 Puppies, 13 Years, and a Genetic Dead End, which takes a different angle.

Farmers and gardeners can support bee health by planting diverse flowers that provide a range of beneficial compounds. This may help bees naturally manage diseases and reduce the need for chemical treatments. Context on how this played out before sits in Animal Valentine Puns: 275+ Sweet Lines That Spark Laughter (Guide). A companion piece, Bumblebees Self-Medicate with Quercetin to Fight Fungal Infections, approaches the same subject from another angle.