Monnin Thibaud, Cini Alessandro, Lecat Vincent, Fédérici Pierre, Doums Claudie
Laboratoire Ecologie et Evolution CNRS UMR 7625, Université Pierre et Marie Curie-Paris, 75005 Paris, France.
Proc Biol Sci. 2009 May 7;276(1662):1593-601. doi: 10.1098/rspb.2008.1739. Epub 2009 Jan 20.
Social insect societies are outstanding examples of cooperation and conflict. Individuals work together, yet seek to increase their inclusive fitness at each others' expense. One such conflict is over colony inheritance, when a queen inherits the colony following the death of the previous queen. Colony inheritance is common in the social wasp Polistes dominulus, and it can have dramatic fitness consequences. The subordinate inheriting the colony is often unrelated to the initial foundress (alpha) and the workers, who therefore get zero inclusive fitness. Workers are capable of mating and reproducing, so that inheritance by a subordinate rather than by a related worker is surprising. Using patterns of egg-laying and egg destruction, we show in 32 laboratory colonies that, upon the removal of alpha, workers fully accepted a subordinate as the new breeder. This new alpha monopolized reproduction to the same extent as alpha, and there was no increase in reproduction by workers and other subordinates. Why workers accept a potentially unrelated subordinate as breeder rather than a full-sister worker is unclear. They may be constrained to do so, and they may seek fitness benefits by producing males later in the season or by absconding the nest.
群居昆虫社会是合作与冲突的典型例子。个体们共同协作，但又试图以牺牲其他个体为代价来提高自身的广义适合度。其中一种冲突是关于蜂群继承，即当前任蜂后死亡后，一只新蜂后继承蜂群。蜂群继承在社会性黄蜂意大利黄蜂中很常见，并且可能产生巨大的适合度后果。继承蜂群的从属个体通常与最初的建群者（蜂后）以及工蜂没有亲缘关系，因此这些工蜂获得的广义适合度为零。工蜂具备交配和繁殖的能力，所以由从属个体而非有亲缘关系的工蜂继承蜂群是令人惊讶的。通过产卵和破坏卵的模式，我们在32个实验室蜂群中发现，当移除蜂王后，工蜂完全接受了一只从属个体作为新的繁殖者。这只新蜂后在独占繁殖方面与原蜂后程度相同，并且工蜂和其他从属个体的繁殖没有增加。为何工蜂会接受一只可能没有亲缘关系的从属个体作为繁殖者而非亲姐妹工蜂尚不清楚。它们可能是受到限制才这样做，并且可能通过在季节后期产雄蜂或者弃巢来寻求适合度利益。
