Hagbery Jessica, Nieh James C
Section of Ecology, Behavior, and Evolution, Division of Biological Sciences, University of California, San Diego, 9500 Gilman Drive, MC0116, La Jolla, CA 92093-0116, USA.
Naturwissenschaften. 2012 Oct;99(10):821-32. doi: 10.1007/s00114-012-0964-7. Epub 2012 Sep 11.
Foraging specialization plays an important role in the ability of social insects to efficiently allocate labor. However, relatively little is known about the degree to which individual bumble bees specialize on collecting nectar or pollen, when such preferences manifest, and if individuals can alter their foraging preferences in response to changes in the colony workforce. Using Bombus impatiens, we monitored all foraging visits made by every bee in multiple colonies and showed that individual foragers exhibit consistent lifetime foraging preferences. Based upon the distribution of foraging preferences, we defined three forager types (pollen specialists, nectar specialists, and generalists). In unmanipulated colonies, 16-36 % of individuals specialized (≥90 % of visits) on nectar or pollen only. On its first day of foraging, an individual's foraging choices (nectar only, pollen only, or nectar and pollen) significantly predicted its lifetime foraging preferences. Foragers that only collected pollen on their first day of foraging made 1.61- to 1.67-fold more lifetime pollen foraging visits (as a proportion of total trips) than foragers that only collected nectar on their first foraging day. Foragers were significantly larger than bees that stayed only in the nest. We also determined the effect of removing pollen specialists at early (brood present) or later (brood absent) stages in colony life. These results suggest that generalists can alter their foraging preferences in response to the loss of a small subset of foragers. Thus, bumble bees exhibit individual lifetime foraging preferences that are established early in life, but generalists may be able to adapt to colony needs.
觅食专业化在群居昆虫有效分配劳动力的能力中起着重要作用。然而，对于单个熊蜂在采集花蜜或花粉方面的专业化程度、这种偏好何时显现，以及个体是否能根据蜂群劳动力的变化改变其觅食偏好，我们了解得相对较少。我们以熊蜂为研究对象，监测了多个蜂群中每只蜜蜂的所有觅食出行情况，结果表明个体觅食者在其一生中表现出一致的觅食偏好。基于觅食偏好的分布情况，我们定义了三种觅食者类型（花粉专家型、花蜜专家型和通才型）。在未受操控的蜂群中，16% - 36%的个体仅专门（≥90%的出行）采集花蜜或花粉。在觅食的第一天，个体的觅食选择（仅花蜜、仅花粉或花蜜和花粉）能显著预测其一生的觅食偏好。在觅食第一天仅采集花粉的觅食者，其一生的花粉觅食出行次数（占总出行次数的比例）比在觅食第一天仅采集花蜜的觅食者多1.61至1.67倍。觅食者明显比只待在蜂巢里的蜜蜂体型更大。我们还确定了在蜂群生活的早期（有幼虫）或后期（无幼虫）阶段移除花粉专家型觅食者所产生的影响。这些结果表明，通才型觅食者能够根据一小部分觅食者的损失改变其觅食偏好。因此，熊蜂表现出在生命早期就确立的个体一生觅食偏好，但通才型觅食者可能能够适应蜂群的需求。
