Worker Policing in Social Hymenoptera

群居的蚂蚁、蜜蜂和黄蜂提供了动物世界中令人着迷的合作范例。然而，现代进化理论认为，在一个昆虫群体中，应该存在着相当大的繁殖冲突。特别是，个体工人和女王之间应该有关于男性生产的冲突。(工蚁、蜜蜂和黄蜂都是雌性。在大多数物种中，工蜂不能交配，但可以产下未受精卵，这些卵发育成雄性。)理论表明，个体工蜂应该更愿意抚养自己的儿子，而不是自己的兄弟，也就是蚁后的儿子，因为从基因上讲，它们与儿子的关系比兄弟更密切。在一些群居昆虫物种中，例如大黄蜂，工蜂会产生许多蜂群中的雄性，而在其他物种中，例如蜜蜂和黄马蜂，所有的雄性都是蜂王的儿子。工蜂产生的雄性蜜蜂的缺失被认为是由于工蜂相互吃对方的卵，从而阻止对方繁殖。这种“工蜂监管”显然是在蜜蜂中进化出来的，因为蜂王与许多雄性交配。这导致工人与女王的儿子的基因关系比与其他工人的儿子（大多数是同父异母的姐妹）更密切，因此阻止其他工人繁殖符合每个工人的基因利益。相比之下，大黄蜂女王只与一只雄蜂交配，因此工蜂与工蜂的儿子（他们都是直系姐妹）的关系比与女王的儿子的关系更密切，并且不应该阻止彼此的繁殖。这个研究项目将更详细地研究蜜蜂的工蜂监管机制，并观察黄马蜂，看看这些昆虫是否也会通过不同的卵移除来进行工蜂监管。一个重要的研究领域将调查工蜂如何通过寻找蜂王产生的化学物质（信息素）来区分工蜂产下的雄卵和蜂王产下的雄卵，这种化学物质可能会给它们的卵带来独特的气味。此外，该项目将量化正常蜂箱中工蜂产卵的产出率，并观察工蜂进入含有雄性卵的蜂房的行为，以确定一些工蜂是否是特殊的“警察蜂”。

Colonies of social ants, bees, and wasps provide fascinating examples of cooperation in the animal world. However, modern evolutionary theory suggests that there should be considerable conflict over reproduction within an insect colony. In particular, there should be conflict between individual workers and the queen over male production. (Worker ants, bees, and wasps are females. In most species, workers cannot mate but can lay unfertilized eggs, which develop into males.) Theory suggests that individual workers should prefer to rear their own sons rather than their brothers, the sons of the queen, because they are more genetically related to sons than brothers. In some species of social insects, for example, bumble bees, workers produce many of the colony's males, whereas in others, for example, honey bees and yellowjacket wasps, all the males are sons of the queen. The absence of male honey bees produced by workers is thought to result from workers preventing each other from reproducing by eating each other's eggs. This "worker policing" has apparently evolved in the honey bee because the queen mates with many males. This leads to workers being more genetically related to the queen's sons than to the sons of other workers (who are mostly half-sisters), so that it is in each worker's genetic interest to stop other workers from reproducing. In contrast, bumble-bee queens mate with only one male, so that workers are more related to the sons of the workers (who are all full sisters) than to the queen's sons, and should not stop each other from reproducing. This research project will examine in more detail the mechanism of worker policing in honey bees, and also look at yellowjacket wasps to see if worker policing by differential egg removal occurs in these insects as well. One important area of research will investigate how worker honey bees can distinguish queen- from worker-laid male eggs, by looking for a queen-produced chemical (pheromone) that may give their eggs a distinctive odor. In addition, the project will quantify the rate of production of worker-laid eggs in normal bee hives, and will look at the behavior of worker bees entering cells containing male eggs to see if some workers are special "police bees."