In the presence of territorial dominant ant species, lower-ranked ants change their foraging strategy by shifting their activity in time and space and by switching to suboptimal food sources. Although important for many insect species, pollen is a rarely used food source by ants. Occasional pollen consumption was demonstrated only in a handful of ant species that are mainly lower-ranked in the competitive hierarchy. We hypothesized that the consumption of pollen by subordinate ants might be enhanced by competitive pressure exerted by dominant species. In the frame of the current study, we assessed the food preference of ant species within a supercolony of the territorial wood ant Formica polyctena by offering them pollen and animal protein baits. Subordinate ant species, especially Myrmica ants, exploited both pollen and animal protein, while F. polyctena foraged only for animal protein. The Myrmica ants exploited pollen sources more intensively on plots where F. polyctena dominated animal protein baits, thus interspecific competition was stronger. As suggested by our study, under suboptimal conditions, where food availability is hindered, e.g. by the presence of superior competitors, pollen can, indeed, be used as a food source by subordinate ants.

中文翻译：

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领土的竞争压力促进了欧洲温带林地下属蚂蚁对不寻常食物来源的利用

在存在领土优势蚂蚁物种的情况下，排名较低的蚂蚁通过在时间和空间上转移活动并转向次优食物来源来改变其觅食策略。虽然对许多昆虫物种很重要，但花粉是蚂蚁很少使用的食物来源。偶尔花粉消耗仅在少数主要在竞争等级中排名较低的蚂蚁物种中得到证实。我们假设优势物种施加的竞争压力可能会增强从属蚂蚁对花粉的消耗。在当前研究的框架内，我们通过向蚂蚁提供花粉和动物蛋白诱饵来评估领地木蚁 Formica polyctena 超级群落内的蚂蚁物种的食物偏好。从属蚂蚁物种，特别是 Myrmica 蚂蚁，利用花粉和动物蛋白，而 F. polyctena 只为动物蛋白觅食。Myrmica 蚂蚁在 F. polyctena 以动物蛋白诱饵为主的地块上更密集地利用花粉来源，因此种间竞争更强。正如我们的研究所表明的那样，在次优条件下，食物供应受到阻碍，例如存在优势竞争者，花粉确实可以被下属蚂蚁用作食物来源。