Territorial behavior is widespread throughout the animal kingdom, with responses to
conspecific intruders differing depending on various ecological, life history, and social …

Drawing on an idea proposed by Darwin, it has recently been hypothesized that violent
intergroup conflict might have played a substantial role in the evolution of human …

Conflict with conspecifics from neighbouring groups over territory, mating opportunities and
other resources is observed in many social organisms, including humans. Here we …

The evolution of cooperative breeding has been traditionally attributed to the effect of kin
selection. While there is increasing empirical evidence that direct fitness benefits are …

The group augmentation (GA) hypothesis states that if helpers in cooperatively breeding
animals raise the reproductive success of the group, the benefits of living in a resulting …

We review the literature on various approaches to modeling animal intergroup conflict
behavior in theoretical biology, highlight the intricacies emerging in the process of adding …

The 30 species of Turdoides babblers range from communal to cooperative, most displaying
some degree of social behavior. Distributed across much of the African continent and …

Out-group conflict is rife in the natural world, occurring from primates to ants. Traditionally,
research on this aspect of sociality has focused on the interactions between groups and their …

In social species, conflict with outsiders is predicted to affect within-group interactions and
thus influence group dynamics and the evolution and maintenance of sociality. Although …

Group territory defence poses a collective action problem: individuals can free-ride,
benefiting without paying the costs. Individual heterogeneity has been proposed to solve …