首次重大转变：从多级选择视角看生命的起源
The first major transition: Origin of life from a multilevel selection perspective
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中文总结 AI 辅助
该研究从多级选择视角，通过数学建模提出生命起源的共生模型，确定携带复制子的原细胞进化固定的条件，阐明从化学集合到细胞的关键事件顺序。
中文摘要 AI 辅助
生命的起源可说是进化（MTE）中首个、最重要且最神秘的重大转变。与所有重大转变一样，只有在多级选择的概念框架内，才能对生命起源的转变进行建设性探讨。与生命起源相关的两个选择层级是复制子和繁殖子，即能够通过原始分裂形式进行繁殖的区室（原细胞）。本文提出的生命起源共生模型认为，细胞生命之前存在着含有原始代谢网络但不含遗传元件（复制子）的原细胞。复制子最初可能是原细胞内仅因复制效率被选择的自私元件，但随后会进化为共生体，使得繁殖子-复制子联合体成为新的集体选择单位。对复制子-繁殖子协同进化的数学建模，确定了携带复制子的原细胞能够胜过空原细胞的条件：为使携带复制子的原细胞在进化中固定，复制必须与原细胞分裂耦合，且对最高复制率的选择需被部分抑制。在进化的最早阶段，随机、随机的原细胞分裂比对称分裂更具优势。多级选择视角阐明了从化学集合到拥有基因组、对称细胞分裂及抗寄生虫防御系统的细胞的进化路线上关键事件的可能顺序。
英文摘要
The origin of life is the first, arguably, the most important and also the most enigmatic major transition in evolution (MTE). As all MTE, the transition at the origin of life can be constructively addressed only within the conceptual framework of multilevel selection. The two levels of selection relevant for the origin of life are replicators, and reproducers, that is, compartments (protocells) capable of reproduction via a primitive form of division. The symbiotic model for the origin of life presented here posits that cellular life was preceded by protocells that harbored proto-metabolic networks but not genetic elements (replicators), Replicators could have started as selfish elements inside protocells selected only for replication efficiency, but subsequently, would evolve into mutualists such that the reproducer-replicator union became a new, collective unit of selection. Mathematical modeling of replicator-reproducer coevolution identifies the conditions under which replicator-carrying protocells can outcompete empty protocells. For the replicator-carrying protocells to and get fixed in evolution, replication has to be coupled with protocell division, selection for the highest replication rate being partially suppressed. At the earliest stages of evolution, random, stochastic protocell division was advantageous compared to symmetrical division. The multilevel selection perspective illuminates the likely order of key events on the evolutionary route from ensembles of chemicals to cells endowed with genomes, symmetrical cell division and anti-parasite defense systems.
