Data from: Lack of aggression and apparent altruism towards intruders in a primitive termite

In eusocial insects, the ability to discriminate nest-mates from non-nest-mates is widespread and ensures that altruistic actions are directed towards kin and agonistic actions are directed towards non-relatives. Most tests of nest-mate recognition have focused on hymenopterans, and suggest that cooperation typically evolves in tandem with strong antagonism towards non-nest-mates. Here, we present evidence from a phylogenetically and behaviourally basal termite species that workers discriminate members of foreign colonies. However, contrary to our expectations, foreign intruders were the recipients of more rather than less cooperative behaviour and were not subjected to elevated aggression. We suggest that relationships between groups may be much more peaceable in basal termites compared with eusocial hymenoptera, owing to energetic and temporal constraints on colony growth, and the reduced incentive that totipotent workers (who may inherit breeding status) have to contribute to self-sacrificial intergroup conflict.

在真社会性昆虫（eusocial insects）中，区分巢友与非巢友的能力广泛存在，该能力可确保利他行为仅指向亲属，而争斗行为则针对非亲属。目前绝大多数巢友识别相关实验均以膜翅目昆虫（Hymenoptera）为研究对象，相关结果提示，合作行为的演化通常伴随对非巢友的强烈敌对行为。本研究从系统发育与行为学层面均属于基干类群的白蚁（termite）物种中获取实验证据，显示其工蚁能够辨别外来蚁群的个体。然而与我们的预期相悖，外来入侵者获得的合作行为反而更多，且未受到增强的攻击。我们推测，相较于真社会性膜翅目昆虫，基干类群白蚁的群体间关系可能更为和平，这一现象可归因于：群体生长受到能量与时间的双重限制，且全能型工蚁（可继承繁殖地位）参与牺牲自我的群体间冲突的动机显著降低。