The mechanistic basis of slow-fast phenotypic diversity and its functional and evolutionary significance in social groups

为什么有些动物像野兔一样快，而另一些动物像乌龟一样慢，这个问题不仅引起了生物学家的兴趣，也引起了哲学家和广大公众的兴趣。有时也被称为生活节奏，这些生理、行为和生活史上的慢快差异，整合成一组对比鲜明的特征，可以沿着沿着一条慢快轴区分不同物种或一个物种内的不同个体。由于能量使用率或代谢率对动物的整体生活方式有很大的影响，该项目将利用两种蜜蜂的遗传品系，这些蜜蜂已经被培育为低代谢率和高代谢率，以了解慢-快差异的根本基础。更重要的是，由于蜜蜂群体是超个体，它们允许人们问一个集体的慢-快表型如何从群体成员的多样性中出现，并在群体水平上定义性能。在不同种类的蜜蜂中也可以看到慢-快的差异，例如在洞穴中筑巢的蜜蜂比在开放中筑巢的蜜蜂具有更快的克里思。该项目还将对四种不同的物种进行比较研究，以了解生态如何塑造慢-快多样性。这项研究的结果将增加我们对慢-快差异的理解，以及它如何有助于社会行为的进化。随着目前对人为变化的关注，了解这些行为和生活史的差异对蜜蜂的健康和管理有影响。该项目还将为学校科学计划中使用的模块做出贡献，该计划支持K-5科学课程，并为对动物行为感兴趣的本科生建立学生导师计划。生理、行为和生活史的快慢差异是行为和进化生态学中的经典和基本概念，其历史源于r-和k-选择。最近，代谢率（MR）和认知方式被认为是这些表型差异的主要驱动因素，在生活节奏框架下被建模为一组相关性状。这种慢-快多样性在社会群体的背景下特别有趣，其中群体水平上的表型表达是其成员的表型多样性的紧急结果，这也使得群体有可能超越个体水平上不同性状之间的协方差可能施加的一些约束。使用慢（低MR）和快（高MR）蜜蜂遗传系的实验杠杆作用（Apis mellifera），本项目将采取一种综合方法，以Tinbergen的四个问题为模型，了解（1）慢-快差异的机制和发育基础，（2）群体水平上慢-快表型多样性的功能后果，（3）通过与A. mellifera与其它3种蜜蜂的差异不显著，A. cerana，中华绒螯蟹A. dorsata和A. florea，前两个是腔巢，后两个是开放巢。总之，这些研究将提供一个慢-快的表型多样性，表征不同层次的生物组织的意义的全面理解。这个奖项反映了NSF的法定使命，并已被认为是值得通过评估使用基金会的智力价值和更广泛的影响审查标准的支持。

Why some animals are fast as hares and others as slow as tortoises is a question that has not only intrigued biologists but also philosophers and the public at large. Sometimes referred to as the pace of life, these slow-fast differences in physiology, behavior and life history, integrated into a set of contrasting characteristics, can distinguish different species or different individuals within a species along a slow-fast axis. Since the rate of energy use, or metabolic rate, can have a large impact in defining the overall lifestyle of an animal, this project will take advantage of two genetic lines of honeybees that have been bred for their low and high metabolic rates, to understand the fundamental basis of slow-fast differences. Even more importantly, since honeybee colonies are superorganisms, they allow one to ask how a collective slow-fast phenotype can emerge from the diversity among colony members and define performance at the group level. Slow-fast differences are also seen among the different species of honeybees such that the ones which nest in cavities have a faster tempo than the ones which nest in the open. This project will also undertake a comparative study of the four different species to understand how ecology shapes slow-fast diversity. The results of this study will add to our understanding of slow-fast differences and how it contributes to the evolution of social behavior. With the current concern about anthropogenic changes, understanding these differences in behavior and life history has implications for honeybee health and management. This project will also contribute to modules for use in the Science for School program which supports K-5 science curriculum and establish a student mentorship program for undergraduates with interests in animal behavior. It will also provide students with opportunities to travel and participate in research internationally.Slow-fast differences in physiology, behavior and life history is a classic and fundamental concept in behavioral and evolutionary ecology, owing its history to r- and k-selection. More recently, metabolic rate (MR) and cognitive style have been cited as the primary drivers of these phenotypic differences, modeled as a set of correlated traits under the pace-of-life framework. Such slow-fast diversity is especially interesting in the context of a social group where the phenotypic expression at the group level is an emergent outcome of the phenotypic diversity of its members, which also makes it possible for the group to potentially override some of the constraints that might be imposed by the covariance among the different traits at the individual level. Using the experimental leverage of the genetic lines of Slow (low MR) and Fast (high MR) honeybees (Apis mellifera) that were bred, this project will take an integrative approach modeled on Tinbergen’s four questions to understand (1) the mechanistic and developmental bases of slow-fast differences, (2) the functional consequences of slow-fast phenotypic diversity at the group level, and (3) the evolutionary basis of slow-fast phenotypic differences and its ecological drivers using a comparative approach integrating the work with A. mellifera with that in the other three honeybee species, A. cerana, A. dorsata and A. florea, the first two being cavity-nesters and the latter two being open-nesters. Together, these studies will provide a comprehensive understanding of the significance of slow-fast phenotypic diversity that characterizes different levels of biological organization.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.