Data from: The biased evolution of generation time

Many life-history traits are important determinants of the generation time. For instance, semelparous species whose adults reproduce only once have shorter generation times than iteroparous species that reproduce on several occasions – assuming equal development duration. A shorter generation time ensures a higher growth rate in stable environments where resources are in excess, and is therefore a positively selected feature in this situation. In a stable and limiting environment, all combinations of traits that produce the same number of viable offspring are selectively equivalent. Here we study the neutral evolution of life-history strategies with different generation times, and show that the slowest strategy represents the most likely evolutionary out- come when mutation is considered. Indeed, strategies with longer generation times generate fewer mutants per time unit, which makes them less likely to be replaced within a given time period. This ‘turnover bias’ favors the evolution of strategies with long generation times. Its real impact, however, depends on both the population size and the nature of selection on life-history strategies. The latter is primarily impacted by the relationships between life- history traits whose estimation will be crucial to understand the evolution of life-history strategies.诸多生活史特征（life-history traits）均为世代时间（generation time）的重要决定因子。例如，在发育时长相等的前提下，仅繁殖一次的一次生殖物种（semelparous species），其世代时间短于可多次繁殖的多次生殖物种（iteroparous species）。在资源充足的稳定环境中，更短的世代时间可带来更高的生长速率，因此在此类情境下属于正选择性状。在稳定且资源受限的环境中，所有可产生相同数量可存活后代的性状组合均具有选择等价性。本研究针对不同世代时间的生活史策略（life-history strategies）开展中性进化（neutral evolution）分析，结果显示，当考虑突变效应时，世代时间最长的策略为最有可能出现的进化结局。究其原因，世代时间更长的策略，单位时间内产生的突变体（mutants）数量更少，因此在给定时间段内被替代的概率更低。这种周转偏倚（turnover bias）会促进世代时间更长的策略的演化。然而，其实际影响同时取决于种群大小（population size）以及生活史策略所受选择的本质。后者主要受生活史特征间关联关系的影响，对这些关联关系的量化估算，将是解析生活史策略演化机制的关键所在。