Effects of social organization and resource availability on brood parasitism in the facultatively social nocturnal bee Megalopta genalis
Effects of social organization and resource availability on brood parasitism in the facultatively social nocturnal bee Megalopta genalis
复制标题
社会组织和资源可用性对兼性群居性夜行性蜜蜂大翅蜂巢寄生的影响
DOI：
10.1007/s00040-017-0590-7
复制
发表时间：
2018
期刊：
影响因子：
1.3
通讯作者：
W. Wcislo
中科院分区：
文献类型：
--
作者：
Adam R. Smith;Christine Harper;K. Kapheim;M. Simons;Callum Kingwell;W. Wcislo
要理解社会合作的演变，关键是要理解群体生活而不是独自生活的进化可能选择的生态效益。对寄生虫和捕食者等天敌的防御通常被认为是一种好处，但大多数研究只关注捕食者。在蜜蜂中，寄生是幼虫死亡的主要来源。在这里，我们使用夜间活动的、新热带的兼性群居蜜蜂Megalopta genalis(Halictidae)来直接比较同一地点的群居和独居蜂巢在资源可获得性高和低的时候的寄生率。我们关注四种寄生虫：一种吃一些花粉但不杀死寄主后代[苍蝇Fiebrigella sp(绿蝇科)]和三种杀死寄主后代的寄生虫(甲虫Macrosiagon gracilis(Rhipiphoridae)、黄蜂Lophostigma cincta(Mutillidae)和同属蜜蜂M.Noctoraptor byroni)。我们发现四种寄生虫在社交巢和孤巢之间的寄生率没有差别。在所有巢中，25-31%的孵化细胞被棉铃虫寄生，从旱季到雨季，这种寄生增加，尽管这种季节性影响仅在群居巢中显著。只有4%的孵化细胞被其他三种寄生虫中的一种寄生，并且只在社会寄主巢中发现了 ~ byroni。我们的数据显示，Megalopta的总体寄生率很低，这不是社会组织或资源可用性的函数。有限的夜间觅食时间和与白天寄生虫活动模式的抵消可能会在保持低寄生率方面发挥更大的作用。
Understanding the ecological benefits that may select for the evolution of living in groups rather than solitarily is key to understanding the evolution of social cooperation. Defense against natural enemies, such as parasites and predators, is generally acknowledged to be such a benefit, but most studies focus only on predators. Among the bees, parasitism is a major source of brood mortality. Here we use the nocturnal, Neotropical, facultatively social bee Megalopta genalis (Halictidae) to directly compare parasitism rates between social and solitary nests at the same site during times of high and low resource availability. We focus on four parasites: one that eats some pollen but does not kill host offspring [the fly Fiebrigella sp (Chloropidae)] and three that kill host offspring (the beetle Macrosiagon gracilis (Rhipiphoridae), the wasp Lophostigma cincta (Mutillidae), and the congeneric bee M. Noctoraptor byroni). We found no difference in parasitism between social and solitary nests for the four parasites tested. Across all nests, 25–31% of brood cells were parasitized by Lophostigma sp., with parasitism increasing from the dry to wet season, although this seasonal effect was significant only for social nests. Only ~ 4% of brood cells were parasitized by one of the other three parasites, and M. byroni was only found in social host nests. Our data reveal that Megalopta have low rates of parasitism overall, and that this is not a function of social organization or resource availability. Limited nocturnal foraging time and foraging offset from the activity patterns of diurnal parasites may instead play a larger role in keeping parasitism rates low.