Data from: Policing is more effective against eggs of non-natal versus natal workers at early colony stages in a bumblebee

Eusocial insect colonies are vulnerable to exploitation by egg-laying
workers arising either as natal reproductive workers or as non-natal
reproductive 'drifting' workers (intraspecific social
parasites). Worker egg-laying is potentially costly to the colony, but
queens and workers can counter its costs via egg-eating (queen or worker
policing). Bumblebee colonies exhibit egg laying by both natal and
non-natal workers: natal workers collectively lay more eggs but do so only
after a specific point in the colony cycle, the ‘competition point’,
whereas non-natal workers potentially lay eggs throughout the colony
cycle. These features create a special opportunity to investigate whether
policing of worker-laid eggs is context-dependent (i.e. depends on worker
origin of eggs and/or colony stage). We introduced artificial egg cells
containing eggs laid by either natal or non-natal workers into colonies of
the bumblebee Bombus terrestris both before and after their competition
points, and observed the fate of introduced egg cells and eggs. In both
colony stages, the majority of introduced egg cells and eggs were policed,
demonstrating that policing was not activated only after the competition
point. However, in the pre-competition point stage alone, a smaller
proportion of non-natal workers' eggs (15%) remained after 20 h
compared to the proportion of natal workers' eggs remaining (24%).
More effective policing of non-natal workers' eggs early in the
colony cycle potentially represents an adaptive, context-dependent
response to the stage in the cycle when all worker-laid eggs are normally
unrelated to the natal colony.

真社会性昆虫（eusocial insect）群落易遭产卵工蜂的寄生性剥削，此类工蜂既可为本巢繁殖工蜂（natal reproductive workers），也可为异巢繁殖的“漂移”工蜂（non-natal reproductive 'drifting' workers，即种内社会寄生虫（intraspecific social parasites））。工蜂产卵会对群落产生潜在代价，但蜂王与工蜂可通过食卵行为——即蜂王监督与工蜂监督（queen or worker policing）——抵消该类代价。熊蜂群落中，本巢工蜂与异巢工蜂均存在产卵行为：本巢工蜂的总产卵量更高，但仅在群落周期的特定节点“竞争点（competition point）”之后才启动产卵；而异巢工蜂则可在整个群落周期内随时产卵。上述特征为探究工蜂所产卵的清除行为是否具备情境依赖性（即取决于卵的产用工蜂来源和/或群落发育阶段）提供了独特研究契机。我们将分别携带本巢工蜂卵与异巢工蜂卵的人工卵室（artificial egg cells），植入于地熊蜂（Bombus terrestris）群落的竞争点前后两个阶段，并持续观测植入卵室及卵的最终去向。结果显示，在两个群落发育阶段中，绝大多数植入的卵室与卵均被清除，这表明卵监督行为并非仅在竞争点之后才被激活。然而，仅在竞争点前阶段，异巢工蜂卵在20小时后的留存比例（15%）显著低于本巢工蜂卵的留存比例（24%）。在群落周期早期对异巢工蜂卵实施更高效的清除行为，或代表了一种适应性的情境依赖响应，适配于整个群落周期内所有工蜂所产卵均与本巢无亲缘关系的发育阶段。