Data from: Ants medicate to fight disease

Parasites are ubiquitous, and the ability to defend against these is of paramount importance. One way to fight diseases is self-medication, which occurs when an organism consumes biologically active compounds to clear, inhibit or alleviate disease symptoms. Here, we show for the first time that ants selectively consume harmful substances (Reactive Oxygen Species, ROS) upon exposure to a fungal pathogen, yet avoid these in the absence of infection. This increased intake of ROS, while harmful to healthy ants, leads to higher survival of exposed ants. The fact that ingestion of this substance carries a fitness cost in the absence of pathogens rules out compensatory diet choice as the mechanism, and provides evidence that social insects medicate themselves against fungal infection, using a substance that carries a fitness cost to uninfected individuals.寄生虫无处不在，生物体抵御此类寄生虫的能力至关重要。对抗疾病的途径之一为自我药疗（self-medication），即生物体通过摄入具有生物活性的化合物，以清除、抑制或缓解疾病症状。本研究首次证实，蚂蚁在接触真菌病原体时，会选择性摄入有害物质活性氧（Reactive Oxygen Species，ROS），而在未受感染的情况下则会规避此类物质。尽管这种增加的ROS摄入对健康蚂蚁具有危害性，但却能提升受感染蚂蚁的存活率。在未接触病原体的条件下摄入该物质会产生适合度代价（fitness cost），这一事实排除了补偿性饮食选择作为其作用机制的可能性，并为社会性昆虫通过使用对未感染个体存在适合度代价的物质，实现对真菌感染的自我药疗提供了实证依据。