Cyclic dominance offers not just a way to maintain biodiversity, but also serves as a sort of defensive alliance against an external invader. Interestingly, a new level of competition can be observed when two cyclic loops are present. Here the inner invasion speed plays a decisive role on the evolutionary outcome, because faster invasion rate provides an evolutionary advantage to an alliance. In this Letter we demonstrate that the heterogeneity of inner invasion rates makes an alliance vulnerable against a loop where group members are equal. Quite surprisingly, a loop where invasion rates are uniform can still dominate an alliance formed by heteregeneous rates even if the average speed of invasion is significantly higher in the latter group. At a specific range of parameter space, when intergroup invasion or the average inner invasion is moderate, the heterogeneous alliance with higher internal invasion speed may prevail, or the system terminates onto a novel 4- or 5-species solution.

中文翻译：

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平等伙伴在防御性联盟中做得更好

周期性优势不仅提供了一种维持生物多样性的方式，而且还充当了一种抵御外部入侵者的防御联盟。有趣的是，当存在两个循环循环时，可以观察到新的竞争水平。在这里，内部入侵速度对进化结果起着决定性作用，因为更快的入侵速度为联盟提供了进化优势。在这封信中，我们证明了内部入侵率的异质性使联盟容易受到群体成员平等的循环的影响。相当令人惊讶的是，即使平均入侵速度在后一组中明显更高，入侵率均匀的循环仍然可以主导由异构率形成的联盟。在特定的参数空间范围内，当群间侵入或平均内侵入中等时，