New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand.
Phys Biol. 2013 Jun;10(3):035001. doi: 10.1088/1478-3975/10/3/035001. Epub 2013 Jun 4.
The evolution of multicellular organisms from unicellular counterparts involved a transition in Darwinian individuality from single cells to groups. A particular challenge is to understand the nature of the earliest groups, the causes of their evolution, and the opportunities for emergence of Darwinian properties. Here we outline a conceptual framework based on a logical set of possible pathways for evolution of the simplest self-replicating groups. Central to these pathways is the recognition of a finite number of routes by which genetic information can be transmitted between individual cells and groups. We describe the form and organization of each primordial group state and consider factors affecting persistence and evolution of the nascent multicellular forms. Implications arising from our conceptual framework become apparent when attempting to partition fitness effects at individual and group levels. These are discussed with reference to the evolutionary emergence of individuality and its manifestation in extant multicellular life-including those of marginal Darwinian status.
多细胞生物是从单细胞对应物进化而来的，这涉及到达尔文个体性从单个细胞向群体的转变。一个特别的挑战是要理解最早的群体的本质、它们进化的原因，以及达尔文属性出现的机会。在这里，我们概述了一个基于最简单的自我复制群体进化的可能途径的逻辑集合的概念框架。这些途径的核心是认识到遗传信息可以在单个细胞和群体之间传递的有限途径。我们描述了每个原始群体状态的形式和组织，并考虑了影响初生多细胞形式的持久性和进化的因素。当试图在个体和群体水平上划分适应度效应时，我们的概念框架所产生的影响就变得明显了。我们将这些影响与个体的进化出现及其在现存多细胞生命中的表现（包括那些具有边缘达尔文地位的生命）进行了讨论。
