Gobin Bruno, Heinze Jürgen, Strätz Michaela, Roces Flavio
Laboratory of Entomology, K.U. Leuven, Naamsestraat 59, B-3000 Leuven, Belgium.
J Insect Physiol. 2003 Aug;49(8):747-52. doi: 10.1016/s0022-1910(03)00111-2.
In a variety of social animals, individuals can secure reproductive rights through aggressive dominance. Direct individual benefits of aggression are widely recognized, but underlying costs affecting group productivity, and thus indirect benefits, are less clear. Costs of aggressive regulation of reproduction are especially important in small social insect colonies, where individual workers could potentially dominate male production. We estimated the energetic costs associated with the regulation of worker reproduction in the ponerine ant Pachycondyla obscuricornis, using the total CO2 emission of a colony as a measure. The level of CO2 emission of 12 experimental colonies varied significantly during five periods with varying levels of aggression and egg-laying. Overall, CO2 emission increased with the degree of fighting in a colony, but was not associated with differences in egg-laying. Aggressive regulation of reproduction and the formation of a dominance hierarchy thus pose an energetic cost to the colony. Furthermore, workers reduce their work-activities immediately after experimental orphaning, giving a further cost to the colony. These costs might influence the outcome of conflicts over male production in ants. This paper presents the first quantification of energetic costs of aggressive behavior regulating reproduction in ants.
在多种群居动物中，个体可通过攻击性优势获得繁殖权。攻击行为的直接个体益处已得到广泛认可，但影响群体生产力的潜在成本以及由此产生的间接益处却不太明确。在小型社会性昆虫群体中，攻击性调节繁殖的成本尤为重要，因为在这类群体中，单个工蚁可能会主导雄蚁的生产。我们以群体的总二氧化碳排放量为衡量标准，估算了猛蚁科暗角厚结猛蚁群体中调节工蚁繁殖所产生的能量成本。在五个具有不同攻击水平和产卵水平的时期内，12个实验群体的二氧化碳排放水平差异显著。总体而言，二氧化碳排放量随群体内战斗程度的增加而上升，但与产卵差异无关。因此，攻击性调节繁殖以及优势等级制度的形成给群体带来了能量成本。此外，在实验性孤雌生殖后，工蚁会立即减少其工作活动，这又给群体带来了额外成本。这些成本可能会影响蚂蚁在雄蚁生产方面的冲突结果。本文首次对蚂蚁中调节繁殖的攻击行为的能量成本进行了量化。
