A quantitative study of worker reproduction in queenright colonies of the Cape honey bee Apis mellifera capensis

Reproduction by workers is rare in honey bee colonies that have an active queen. By not producing their own offspring and preventing other workers from producing theirs, workers are thought to increase their inclusive fitness due to their higher average relatedness towards queen-produced male offspring compared with worker-produced male offspring. But there is one exception. Workers of the Cape honey bee Apis mellifera capensis are able to produce diploid female offspring via thelytokous parthenogenesis and thus produce clones of themselves. As a result, worker reproduction and tolerance towards worker-produced offspring is expected to be more permissive than in arrhenotokous (sub)species where worker offspring are male. Here we quantify the extent to which A. m. capensis workers contribute to reproduction in queenright colonies using microsatellite analyses of pre-emergent brood. We show that workers produced 10.2% of workers and 0.48% of drones. Most of the workers' contribution towar...在有王蜂群中，工蜂自行繁殖的现象极为罕见。学界普遍认为，工蜂通过放弃自身繁殖并抑制其他工蜂繁殖，可提升自身的广义适合度（inclusive fitness）：相较于工蜂产下的雄性后代，工蜂与蜂王产下的雄性后代拥有更高的平均亲缘系数。但存在一类例外：开普蜜蜂（Apis mellifera capensis）的工蜂可通过产雌单性生殖（thelytokous parthenogenesis）产生二倍体雌性后代，从而实现自身克隆。由此可见，相较于后代均为雄性的产雄单性生殖（arrhenotokous）（亚）物种，开普蜜蜂的工蜂繁殖行为以及对工蜂后代的容忍度理应更为宽松。本研究通过对预羽化蜂幼虫开展微卫星（microsatellite）分析，量化了有王蜂群中开普蜜蜂工蜂的繁殖贡献占比。研究结果显示，工蜂产下的后代占工蜂种群的10.2%，占雄蜂种群的0.48%。工蜂的繁殖贡献大多