The effect of group size on the interplay between dominance and reproduction in XXXX .

@entity5681 @entity20993 @entity146
Social insects provide good model systems for testing trade-offs in decision-making because of their marked reproductive skew and the dilemma workers face when to reproduce. Attaining reproductive skew requires energy investment in @entity146 or fertility signaling, creating a trade-off between reproduction and dominance. This may be density-dependent because the cost of achieving dominance may be higher in larger groups. We investigated the effect of group-size in @entity20993 queenless workers on two major reproduction-dominance correlates: between-worker @entity146 , and @entity5681 production, aiming at mimicking decision-making during the transition of worker behavior from cooperation and sterility to aggressive reproductive competition in whole colonies. Despite the competition, reproductive division of labor in colonies can be maintained even during this phase through the production of a sterility signal by sterile workers that has an appeasement effect on dominant nestmates. @entity146 , ovary activation, and production of sterility-appeasement signals may therefore constitute components of a trade-off affecting worker reproduction decisions. By constructing queenless groups of different size and measuring how this affected the parameters above, we found that in all groups @entity146 was not evenly distributed with the a-worker performing most of the aggressive acts. Moreover, @entity146 by the a-worker increased proportionally with group-size. However, while in small groups the a-worker monopolized reproduction, in larger groups several workers shared reproduction, creating two worker groups: reproductives and helpers. It appears that despite the increase of @entity146 , this was evidently not sufficient for the a-worker to monopolize reproduction. If we compare the a-worker to the queen in full-sized colonies it can be hypothesized that worker reproduction in @entity20993 colonies starts due to a gradual increase in the worker population and the queen's inability to physically inhibit worker oviposition. This may shift the trade-off between cost and benefit of worker reproduction and trigger the competition phase.
