Review: Allee effects in social species

摘要: Allee effects have important implications for many aspects of basic and applied ecology. The benefits aggregation conspecific individuals are central to effects, which led the widely held assumption that social species more prone effects. Robust evidence this assumption, however, remains rare. Furthermore, previous research on has failed adequately address consequences different levels organisation within species' populations. Here, we review available model role demographic behavioural factors may combine dampen or strengthen in species. We use examples across various with contrasting structure, including carnivores, bats, primates eusocial insects. Building this, provide a conceptual framework allows integration Social characterised by nested organisation. cooperation, measured mean individual fitness, can be observed at both population group levels, giving rise "population level" "group respectively. also speculate possibility third level, reporting per capita (e.g. castes insects). show size heterogeneity intergroup interactions affect strength population-level Populations higher groups cooperate demonstrate weakest thus an explanation why extinctions due rare More accounting will improve our understanding ecological evolutionary cooperation