2015 has been a good year for ants: Ant-Man was added to the roster of Marvel superheroes and now a recent paper has shown ants participating in zoopharmacognosy – a long, fancy name to describe self-medication by non-human animals.
While self-medicating has been observed in many animals – both vertebrate and invertebrate – it is often hard to discern whether that behavioral instance should be considered true self-medication or not. By developing a well thought out experimental setup, however, scientists from Finland have demonstrated that when ants are infected with a fungus they deliberately consume hydrogen peroxide (H2O2) laced food. H2O2 walks a fine line with these ants: it is clearly detrimental to the healthy ants, but for those infected with the fungus, it increases their chance of survival. More impressively, the fungus-ridden ants appear to know when to begin consuming H2O2 and how much of it they’re consuming.
There are still many questions to be asked: how does the ant know it’s infected; will a similar behavior be observed in other ant species; does self-medication differ in colonial and non-colony dwelling insects? For the moment the answer for most of these questions is, as Nick Bos, the leading author of the paper puts it, “we don’t know… yet.” But that’s how science works: an observation of self-medicating by ants causes one to ask, for instance, what triggers the ant to self-medicate after infection, and this question will go on to be answered, thus generating more questions in a vicious, yet fascinating cycle.
Managing Correspondent: Fernanda Ferreira
Acknowledgments: Special thanks to Leonora Bittleston, a Ph.D. student at Harvard’s Department of Organismic and Evolutionary Biology, and Dr. Nick Bos , first author of the paper and a postdoctoral research at the University of Helsinki, for their time, patience, and expert commentary.
Research Paper: Ants medicate to fight disease – not open access