Life-history Trade-offs and the Evolution of Multicellularity

生活多样化和生活世界等级组织的主要里程碑是一系列个性转变的结果，在这些转变中，以前独立的个体群体变得如此融合，以至于出现了一种新的个体。例如，这类事件包括第一个细胞的起源、多细胞生物体的进化和社会的进化。群体是如何以及为什么进化成个体的？这些是激励我们工作的中心问题。多细胞生物体的进化是将低级个体(细胞)整合为新的高级个体的典型例子，在这种新的高级个体中，细胞在与生存(不育的体细胞)或生殖(生殖细胞)相关的功能上进行合作和专业化(即分工)。这个项目以绿藻为实验模型系统，通过研究这些性状的遗传基础来研究体细胞是如何进化的。负责这一进化的过程将通过检验这一假设来检验，即繁殖成本随着身体大小的增加而增加，这一成本增加的选择是为了增加细胞对影响生殖或生存功能的专门化。该项目是开发Volvocine绿藻作为研究复杂性的模型系统的更大倡议的一部分，就像其他生物为遗传学和发育研究服务一样。该倡议包括Volvocales研究和教育中心，该中心将为高中制定学习计划和教学材料，以促进使用达尔文原理和Volvocine绿藻作为模式系统来研究复杂性。

The major landmarks in the diversification of life and the hierarchical organization of the living world are consequences of a series of transitions in individuality, whereby groups of previously independent individuals become so integrated that a new kind of individual emerges. Such events include, for instance, the origin of the first cell, the evolution of multicellular organisms, and the evolution of societies. How and why do groups evolve into individuals? These are the central questions motivating our work. The evolution of multicellular organisms is the premier example of the integration of lower level individuals (cells) into a new, higher-level individual in which cells co-operate and specialize (i.e., division of labor) at functions related to survival (sterile somatic cells) or reproduction (germ cells). Using the volvocine green algae as an experimental model-system, this project studies how somatic cells evolved by examing the genetic basis for these traits. The processes responsible for that evolution will be examined through tests of the hypothesis that the cost of reproduction increases with body size, with this increasing cost selecting for increasing cellular specialization for functions affecting either reproduction or survival.This project is part of a larger initiative to develop the volvocine green algae as a model system to study complexity, much as other organisms serve the studies of genetics and development. This initiative includes the Volvocales Research and Education Center that will develop study plans and instructional materials for high schools to facilitate the study of complexity using Darwin's principles and the volvocine green algae as a model-system.