Flexible parents: joint effects of handicapping and brood size manipulation on female parental care in Nicrophorus vespilloides

Parental care is highly variable, reflecting that parents make flexible decisions in response to variation in the cost of care to themselves and the benefit to their offspring. Much of the evidence that parents respond to such variation derives from handicapping and brood size manipulations, the separate effects of which are well understood. However, little is known about their joint effects. Here we fill this gap by conducting a joint handicapping and brood size manipulation in the burying beetle Nicrophorus vespilloides. We handicapped half of the females by attaching a lead weight to their pronotum, leaving the remaining females as controls. We also manipulated brood size by providing each female with 5, 20 or 40 larvae. In contrast to what we predicted, handicapped females spent more time provisioning food than controls. We also found that handicapped females spent more time consuming carrion. Furthermore, handicapped females spent a similar amount of time consuming carrion regardle...

亲本抚育（parental care）存在高度变异，反映出亲本可依据自身抚育的成本与后代获得的收益的变化做出灵活决策。当前支持亲本响应此类变异的证据，大多来自负重操控（handicapping）与窝大小操控（brood size manipulations）两类实验，二者各自的效应已得到充分阐明。然而，目前对二者的联合效应却知之甚少。本研究以斑埋葬甲（Nicrophorus vespilloides）为实验对象，通过同时开展负重与窝大小操控填补了这一研究空白。我们为半数雌性个体的前胸背板（pronotum）附着铅坠以施加负重，剩余雌性作为对照；同时通过为每头雌性提供5、20或40头幼虫来操控窝大小。与我们的预测相反，负重雌性的食物投喂时长显著长于对照个体。此外，负重雌性的腐肉（carrion）取食时长也更长；且负重雌性的腐肉取食时长与……