Data files from Extreme lifespan extension in tapeworm-infected ant workers

Social insects are hosts of diverse parasites, but the influence of these parasites on phenotypic host traits is not yet well understood. Here, we tracked the survival of tapeworm-infected ant workers, their uninfected nest-mates and of ants from unparasitized colonies. Our multi-year study on the ant Temnothorax nylanderi, the intermediate host of the tapeworm Anomotaenia brevis, revealed a prolonged lifespan of infected workers compared to their uninfected peers. Intriguingly, their survival over 3 years did not differ from those of (uninfected) queens, whose lifespan can reach two decades. By contrast, uninfected workers from parasitized colonies suffered from increased mortality compared to uninfected workers from unparasitized colonies. Infected workers exhibited a metabolic rate and lipid content similar to young workers in this species, and they received more social care than uninfected workers and queens in their colonies. This increased attention could be mediated by their deviant chemical profile, which we determined to elicit more interest from uninfected nest-mates in a separate experiment. In conclusion, our study demonstrates an extreme lifespan extension in a social host following tapeworm infection, which appears to enable host workers to retain traits typical for young workers.

社会性昆虫是多种寄生虫的天然宿主，但此类寄生虫对宿主表型性状（phenotypic host traits）的影响迄今尚未得到充分解析。本研究针对绦虫短节异带绦虫（Anomotaenia brevis）的中间宿主尼德兰坦诺蚁（Temnothorax nylanderi）开展了长期追踪研究，监测了受感染工蚁、其未受感染的同巢伙伴以及来自未寄生蚁群的蚂蚁的存活情况。研究结果显示，受感染工蚁的寿命显著长于未受感染的同类个体。值得注意的是，受感染工蚁的3年存活率与未受感染的蚁后并无显著差异，而该物种蚁后的自然寿命可达20年。与之形成鲜明对比的是，来自受寄生蚁群的未受感染工蚁，其死亡率显著高于未寄生蚁群中的未受感染工蚁。受感染工蚁的代谢速率与体内脂质含量与该物种的幼年工蚁相近，且它们在蚁群中获得的社会照料量多于未受感染的工蚁与蚁后。这种额外的照料行为可能源于其异常的化学信号特征：我们在独立对照实验中证实，这类特征可引发未受感染同巢伙伴的更多关注。综上，本研究证实，受绦虫感染的社会性宿主工蚁会出现极端的寿命延长现象，且这类受感染工蚁似乎能够维持幼年工蚁的典型性状特征。