Multilevel societies (MLSs), stable nuclear social units within a larger collective encompassing multiple nested social levels, occur in several mammalian lineages. Their architectural complexity and size impose specific demands on their members requiring adaptive solutions in multiple domains. The functional significance of MLSs lies in their members being equipped to reap the benefits of multiple group sizes. Here, we propose a unifying terminology and operational definition of MLS. To identify new avenues for integrative research, we synthesise current literature on the selective pressures underlying the evolution of MLSs and their implications for cognition, intersexual conflict, and sexual selection. Mapping the drivers and consequences of MLS provides a reference point for the social evolution of many taxa, including our own species.

多层次社会（MLS）是包含多个嵌套社会层次的较大集体中的稳定核社会单位，它发生在几个哺乳动物谱系中。它们的体系结构复杂性和规模对其成员提出了特定要求，这些成员需要在多个领域中提供自适应解决方案。MLS的功能意义在于其成员具备从多个小组规模中受益的能力。在这里，我们提出了MLS的统一术语和操作定义。为了确定整合研究的新途径，我们综合了有关MLS进化的潜在选择压力及其对认知，性冲突和性选择的影响的现有文献。绘制MLS的驱动因素和后果，为包括我们自己物种在内的许多生物分类的社会进化提供了参考。