Dissertation Research: The Evolution of Eusociality in the Aphid Tribe Cerataphidini

群居性的进化为进化生物学提出了一个主要的悖论，因为它需要不育个体的进化。蚜虫部落Cerataphidini提供了一个理想的机会来研究群居性的进化，因为这个群体是一种相对原始的群居形式的多态，产生了一个生殖不育的“士兵”种姓。为了研究群居性的起源，pi将首先使用DNA序列数据重建角蚜虫的系统发育，然后将与士兵种姓进化相关的系统发育行为生态数据映射到该系统发育上。pi将通过使用最近开发的统计方法测试这些变量与士兵生产之间的显着关联来测试士兵种姓进化的几个假设。pi建议返回已收集到系统发育中的蚜虫物种的现场，以测量被认为对理解其社会行为进化至关重要的变量。pi将首先对每个物种的菌落进行取样，然后进行遗传分析，以估计菌落内和菌落之间的平均亲缘关系。考虑到空间和时间的变化，pi将测量个体出生率、士兵产量、蚂蚁相互作用、捕食和寄生。所获得的信息将有助于理解关于社会性的基本问题，以及它给这群植食者带来的种群成功或失败。

The evolution of eusociality presents a major paradox for evolutionary biology because it requires the evolution of sterile individuals. The aphid tribe Cerataphidini provides an ideal opportunity to investigate the evolution of eusociality because the group is polymorphic for a relatively primitive form of eusociality, the production of a reproductively sterile "soldier" caste. To examine the origins of eusociality, the PIs will first reconstruct a phylogeny for the cerataphidine aphids using DNA sequence data and then map onto this phylogeny behavioral ecological data pertinent to the evolution of a soldier caste. The PIs will test several hypotheses for the evolution of a soldier caste by testing for significant associations among these variables and soldier production using recently developed statistical methods. The PIs propose to return to field sites where species of aphids included in the phylogeny have been collected to measure variables that are believed critical to understanding the evolution of their social behavior. The PIs will first sample colonies of each species for later genetic analysis to estimate the average relatedness within and between colonies. Taking into account both spatial and temporal variation, the PIs will then measure individual birth rates, soldier production, ant interaction, predation and parasitism. The information obtained will be useful in understanding both fundamental questions about sociality and the population success or failure it brings to this group of plant feeders.