School of Biological Sciences, University of East Anglia, Norwich Research Park, Norwich, Norfolk NR4 7TJ, UK.
Biol Lett. 2013 May 1;9(3):20130056. doi: 10.1098/rsbl.2013.0056. Print 2013 Jun 23.
In eusocial insects, inclusive fitness theory predicts potential queen-worker conflict over the timing of events in colony life history. Whether queens or workers control the timing of these events is poorly understood. In the bumble-bee Bombus terrestris, queens exhibit a 'switch point' in which they switch from laying diploid eggs yielding females (workers and new queens) to laying haploid eggs yielding males. By rearing foundress queens whose worker offspring were removed as pupae and sexing their eggs using microsatellite genotyping, we found that queens kept in the complete absence of adult workers still exhibit a switch point. Moreover, the timing of their switch points relative to the start of egg-laying did not differ significantly from that of queens allowed to produce normal colonies. The finding that bumble-bee queens can express the switch point in the absence of workers experimentally demonstrates queen control of a key life-history event in eusocial insects. In addition, we found no evidence that workers affect the timing of the switch point either directly or indirectly via providing cues to queens, suggesting that workers do not fully express their interests in queen-worker conflicts over colony life history.
在社会性昆虫中，适合度理论预测潜在的蜂王-工蜂冲突，即关于群体生活史中事件发生时间的冲突。蜂王或工蜂是否控制这些事件的发生时间还知之甚少。在熊蜂 Bombus terrestris 中，蜂王表现出一个“转换点”，在此期间，它们从产二倍体卵（产生雌性个体，即工蜂和新蜂王）转变为产单倍体卵（产生雄性个体）。通过饲养发现者蜂王，在蛹期去除其工蜂后代，并使用微卫星基因分型对其卵子进行性别鉴定，我们发现，即使在完全没有成年工蜂的情况下，蜂王仍会表现出转换点。此外，它们的转换点相对于产卵开始的时间与允许产生正常群体的蜂王相比，并没有显著差异。这一发现表明，熊蜂蜂王可以在没有工蜂的情况下表达转换点，这从实验上证明了蜂王对社会性昆虫关键生活史事件的控制。此外，我们没有发现工蜂通过向蜂王提供线索直接或间接地影响转换点时间的证据，这表明工蜂并没有完全表达它们对群体生活史中蜂王-工蜂冲突的兴趣。
