To determine how males of the large carpenter bee, Xylocopa appendiculata, maximize access to females while minimizing energy cost and acquiring energy for territorial flights, we investigated the times of territorial flights by males and foraging by males and females. Males were present continuously in territories from 8:00 to 12:00. They approached, chased, and excluded conspecific males from their territories. In the laboratory, males showed higher locomotor and flight activities in the morning and lower activities in the afternoon. Both males and females visited flowers from 8:00 to 16:00, but the most frequent visits were earlier in females (10:00–12:00) than in males (12:00–13:00). Relative body weights in territorial males often increased. These results indicate that the males time their territorial flights to maximize contact with females and obtain nectar as fuel between and after the territorial flights. The time-related territorial flight in males might be based on a time-keeping system in the brain. Brain levels of serotonin and its precursor tryptophan were significantly higher in males collected at 16:00 than at 11:00, suggesting a relation between time-related territorial flight and serotonin synthesis in the brain.

中文翻译：

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雄性领土飞行的时间以及与大脑中5-羟色胺有关的大型木匠蜜蜂Xylocopa阑尾的觅食。

要确定大型木匠蜜蜂，Xylocopa appendiculata的雄性为了最大限度地利用女性，同时最大程度地降低能源成本并获取领土飞行的能量，我们调查了男性的领土飞行时间和男性和女性的觅食时间。从8:00到12:00，男性在该地区连续出现。他们接近，追捕并将同种的男性排除在其领土外。在实验室中，雄性在早晨表现出较高的运动和飞行活动，而在下午表现出较低的活动和飞行活动。雄性和雌性都在8:00到16:00之间访问花朵，但是雌性（10：00–12：00）的访问频率最高，雄性（12：00–13：00）的访问频率更高。领地男性的相对体重经常增加。这些结果表明，雄性为它们的领土飞行安排时间，以最大程度地与雌性接触，并在该领土飞行之间和之后获取花蜜作为燃料。男性与时间有关的领土飞行可能基于大脑中的计时系统。16:00采集的雄性动物的血清素和其前体色氨酸的脑水平显着高于11:00，表明时间相关的领土飞行与脑中5-羟色胺合成之间的关系。