The quantitative genetics of fitness in a wild seabird

Additive genetic variance in fitness is a prerequisite for adaptive evolution, as a trait must be genetically correlated with fitness to evolve. Despite its relevance, additive genetic variance in fitness has not often been estimated in nature. Here, we investigate additive genetic variance in lifetime and annual fitness components in common terns (Sterna hirundo). Using 28 years of data comprising ca. 6000 pedigreed individuals, we find that additive genetic variances in the Zero-inflated and Poisson components of lifetime fitness were effectively zero, but estimated with high uncertainty. Similarly, additive genetic variances in adult annual reproductive success and survival did not differ from zero, but were again associated with high uncertainty. Simulations suggested that we would be able to detect additive genetic variances as low as 0.05 for the Zero-inflated component of fitness, but not for the Poisson component, for which adequate statistical power would require c. two more de...

适合度的加性遗传方差是适应性进化的先决条件，因为某一性状需与适合度存在遗传相关才能发生进化。尽管其具有重要意义，但自然界中适合度的加性遗传方差尚未得到频繁估算。本文研究了普通燕鸥（Sterna hirundo）终生适合度与年度适合度组分的加性遗传方差。利用涵盖约6000个系谱个体的28年数据，我们发现终生适合度的零膨胀（Zero-inflated）和泊松（Poisson）成分的加性遗传方差实际为零，但估算结果存在高度不确定性。类似地，成鸟年度繁殖成功率与存活率的加性遗传方差与零无显著差异，且同样具有高度不确定性。模拟结果表明，我们能够检测到适合度零膨胀成分中低至0.05的加性遗传方差，但无法检测泊松成分的；若要获得足够统计效力，泊松成分还需约两倍的……