Collaborative Research: Evolutionary Transition from Solitary to Gregarious Development in Parasitoid Wasps

合作研究：寄生蜂从独居发育到群居发育的进化转变。Paul Ode1，James Whitfield 2和George Heimpel31北达科他州立大学2伊利诺伊大学香槟分校3明尼苏达大学双胞胎大学摘要：卵子大小的研究是行为生态学和生活史理论中最古老和最有成效的领域之一。一个中心主题是父母和后代在分配有限的资源和最佳的卵子大小方面的冲突。寄生黄蜂(寄生蜂)一直是研究产卵大小的有利生物，因为它们的宿主代表着明确界定的资源，后代在上面发育。如果每个寄主只有一只幼虫完成发育，则寄生蜂被归类为单亲幼虫，如果每个寄主发育出多个非吸血寄生后代，则寄生蜂被归类为群居幼虫。系统发育模式表明，独居发育是群居的祖先，这种转变已经发生过多次。种群遗传模型表明，有利于非杀姐妹行为传播的条件是严格的，但如果出现以下一个或多个因素，则可能会放松：亲子关系内的性别分配行为增加，幼虫活动丧失，获得区分亲属和非亲属的能力，近亲繁殖，或减少重寄生性。虽然大多数寄生蜂分类群的系统发育关系还不是很清楚，但茧蜂属的系统发育研究得很好，可以详细研究上述因素是否与该属内聚集性的进化有关。从更多的Cotesia物种收集DNA序列将进一步加强系统发育。行为学研究将评估杀害兄弟姐妹、流动性、性别分配和亲属歧视在群居关系演变中的作用。田间和实验室研究将确定近亲交配和重寄生对群居进化的影响。

Collaborative Research: The evolutionary transition from solitary to gregarious development in parasitoid wasps. Paul Ode1, James Whitfield2, and George Heimpel31North Dakota State University2University of Illinois at Urbana-Champaign3University of Minnesota-Twin CitiesAbstract:The study of clutch size is one of the oldest and most productive fields in behavioral ecology and life history theory. A central theme is the conflict between parents and offspring over the allocation of limiting resources and optimal clutch size. Parasitic wasps (parasitoids) have been favored organisms for clutch size studies because their hosts represent well-defined resources on which offspring develop. Parasitoids are classified as solitary if only one, typically siblicidal, larva completes development per host or gregarious if more than one non-siblicidal offspring develops per host. Phylogenetic patterns suggest that solitary development is ancestral to gregariousness and that this transition has occurred many times. Population genetic models suggest the conditions favoring the spread of non-siblicidal behavior are stringent but may be relaxed if one or more of the following factors occur: sex allocation behaviors increase within brood relatedness, loss of larval mobility, acquisition of the ability to distinguish relatives from non-relatives, inbreeding, or reduced superparasitism. While the phylogenetic relationships of most parasitoid taxa are not well understood, the well-studied phylogeny of the braconid genus Cotesia allows detailed study of whether the aforementioned factors were associated with the evolution of gregariousness within this genus. Collection of DNA sequences from additional Cotesia species will further strengthen the phylogeny. Behavioral studies will assess the role of siblicide, mobility, sex allocation, and kin-discrimination in the evolution of gregariousness. Field and laboratory studies will determine the effects of inbreeding and superparasitism on the evolution of gregariousness.