Towards understanding the evolution of workforce organization in social spiders

劳动分工的讨论构成了许多无脊椎动物社会进化文献的基础。劳动分工是一种劳动力组织，其中个人专门从事团队功能所需的维护任务的子集。高水平的个人任务专业化被认为是有益的，因为专家被预测在各自的任务上优于通才，而由不同专业个人组成的群体被预测优于同质群体。劳动分工的好处可能在群居昆虫中得到了最好的证明，然而，现有的数据表明，劳动分工可以提高非群居群体的表现，甚至是参与双亲合作照料的成对个体。尽管它具有直观的吸引力，但一些研究人员认为，任务专业化和加强劳动分工可能并不总是受到青睐，劳动力组织的各个方面，如动态任务转换，可能是社会群体成功的更重要决定因素。在对殖民地施加的要求随时间变化很大的环境中，这一点可能尤其正确。研究人员利用6个独立进化的社会性蜘蛛谱系，分别来自非洲蛛属（新大陆）和剑蛛属（旧大陆），提出：1)描述自然和实验群体的劳动力组织模式；2)测试个体特征与其任务表现之间的关联；3)研究群体间劳动力组织差异与群体成功的联系程度，以及这些关系如何根据周围栖息地（例如，低地雨林与云雾森林）发生变化；4)探索劳动力如何根据生态需求的变化改变其任务表现模式；5)审视自组织在产生社会性蜘蛛所见的劳动力组织模式中的作用。拟议的研究将以一种很少能实现的方式，批判性地评估劳动分工与劳动力组织的其他方面在对比环境中的适应性意义。就它们而言，这些社会性蜘蛛代表了一个非常容易驾驭和经过严格审查的系统，可以进行拟议的研究。

Discussions of division of labor form the basis of much of the literate on social evolution in invertebrates. Division of Labor is a kind of workforce organization where individuals specialize on a subset of the maintenance tasks required for group function. High levels of individual task specialization are argued to be beneficial because specialists are predicted outperform generalists at their respective tasks, and groups composed of diverse sets of specialized individuals are predicted to outperform homogeneous groups. The benefits of division labor are likely best documented in the eusocial insects, however, the available data suggest division of labor can enhance the performance of non-eusocial groups and even pairs of individuals engaged in cooperative biparental care. In spite of its intuitive appeal, some researchers have argued that task specialization and enhanced division of labor might not always be favored, and that aspects of workforce organization like dynamic task switching may be more important determinants of social group success. This may be particularly true in environments where the demands imposed on colonies vary widely through time. Using six independently evolved lineages of social spiders from across the Anelosimus (New World) and Stegodyphus (Old World) genera, we propose to 1) characterize patterns of workforce organization in natural and experimental colonies, 2) test for associations between individuals' traits and their task performance profiles, 3) examine the degree to which between-group differences in workforce organization are linked to group success and how these relationships change based on the surrounding habitat (e.g., lowland rain forests vs. cloud forests), 4) probe how workforces change their patterns of task performance in response to shifts in ecological demands, and 5) scrutinize the role of self-organization in generating the patterns of workforce organization seen in social spiders. The proposed studies will critically evaluate the adaptive significance of division of labor versus other aspects of workforce organization in contrasting environments in a manner rarely achievable. For their part, these social spiders represent are extraordinarily tractable and well vetted system for conducting the proposed studies.