Rank and inheritance in a facultatively eusocial hover wasp
In each L. flavolineata colony only one 'dominant' female reproduces at a given time, but all of the females, apparently, have the potential to achieve dominant status. I provide detailed census data, which shows that the majority of wasps inherit dominance in an age-based manner, i.e. the oldest individual becomes the dominant when the previous dominant dies. However, I also provide evidence of 'cheats' that achieve dominance before older individuals. Focusing upon 'cheating' individuals, I look at their relative size and genetic relatedness in relation to their nestmates to provide clues as to how they are able to 'queue-jump'. This study reveals that queue jumpers tend to be the sisters of wasps they jump in the queue yet queue jumpers are generally no larger than the rest of their nestmates. I then proceed to look at the prior foraging effort of queue jumpers before the queue jump took place. I conclude that queue jumping is an opportunist act performed when the dominant shows cues as to the imminent arrival of her death. I provide data regarding the general genetic structure of L. flavolineata colonies, focusing particularly upon the relatedness of the dominant to subordinate ranks. This study reveals no correlation between rank and relatedness to the dominant. Finally, I look at foraging effort and how it corresponds to rank and group size. Cant and Field (2001) have developed a Kin Selection model in which they predict the optimum levels of foraging effort for a subordinate individual according to its rank and the group size of its nest. L. flavolineata is a suitable species upon which to test this model as rank is revealed to be independent of relatedness to the Dominant. The results shown here are in good agreement with the predictions of the Kin Selection model.