Max Planck Institute for Chemical Ecology, Jena, Germany.
Institute of Integrative Biology, ETH Zürich, Zürich, Switzerland.
Nat Commun. 2023 Aug 26;14(1):5233. doi: 10.1038/s41467-023-40983-7.
In social groups, infection risk is not distributed evenly across individuals. Individual behaviour is a key source of variation in infection risk, yet its effects are difficult to separate from other factors (e.g., age). Here, we combine epidemiological experiments with chemical, transcriptomic, and automated behavioural analyses in clonal ant colonies, where behavioural individuality emerges among identical workers. We find that: (1) Caenorhabditis-related nematodes parasitise ant heads and affect their survival and physiology, (2) differences in infection emerge from behavioural variation alone, and reflect spatially-organised division of labour, (3) infections affect colony social organisation by causing infected workers to stay in the nest. By disproportionately infecting some workers and shifting their spatial distribution, infections reduce division of labour and increase spatial overlap between hosts, which should facilitate parasite transmission. Thus, division of labour, a defining feature of societies, not only shapes infection risk and distribution but is also modulated by parasites.
在社交群体中，感染风险在个体之间的分布并不均匀。个体行为是感染风险变化的一个关键来源，但它的影响很难与其他因素（如年龄）区分开来。在这里，我们结合了流行病学实验和化学、转录组和自动化行为分析，在克隆蚁群中，个体行为在相同的工蚁中出现。我们发现：（1）秀丽隐杆线虫寄生在蚂蚁头上，影响它们的生存和生理；（2）感染的差异仅来自行为的变化，并反映了空间组织的劳动分工；（3）感染通过使受感染的工蚁留在巢中而影响蚁群的社会结构。通过不成比例地感染一些工蚁并改变它们的空间分布，感染会减少劳动分工并增加宿主之间的空间重叠，这应该有助于寄生虫的传播。因此，劳动分工，社会的一个决定性特征，不仅塑造了感染风险和分布，而且还受到寄生虫的调节。
