Providing chicks with extra food lowers male but not female provisioning in the H ouse S parrow P asser domesticus
Providing chicks with extra food lowers male but not female provisioning in the H ouse S parrow P asser domesticus
复制标题
为雏鸟提供额外的食物会降低家麻雀的雄性供给量，但不会降低雌性麻雀的供给量
作者：
Cleasby I
我们评估了成年家麻雀是否会根据雏鸟营养状况的实验增加而调整它们的供给。当我们直接给小鸡补充额外的食物时，雄性父母减少了它们的供给，而不是雌性父母。对雄性的结果，而不是雌性，与之前在这个物种中进行的实验相反。此外，雌性饲料与育雏规模和育雏年龄均呈正相关。相比之下，尽管雄性的供给量与育雏规模呈正相关，但雄性的供给量并没有随着雏鸟的年龄增长而增加。雄性，而不是雌性，在供给上表现出可重复性。食物补充对小窝雏鸟存活率的积极影响大于大窝雏鸟。总的来说，雄性和雌性在如何决定对当前后代的亲代投资水平方面似乎存在根本差异。
We assessed whether adult House SparrowsPasser domesticusadjusted their provisioning in response to an experimental increase in the nutritional condition of their nestlings. When we supplemented chicks directly with additional food, male parents, but not female parents, reduced their provisioning. The results for males, but not females, run contrary to a previous experiment in this species. In addition, female provisioning was positively associated with both brood size and the age of the brood. In contrast, whereas male provisioning was positively associated with brood size, males did not increase provisioning as their chicks grew older. Males, but not females, exhibited repeatability in their provisioning. Food supplementation had a larger positive effect upon nestling survival in smaller broods than in larger broods. Overall, there appear to be fundamental differences between males and females in how decisions regarding the level of parental investment in the current brood are made.