Accurately estimating genetic variance components is important for studying evolution in the wild. Empirical work on domesticated and wild outbred populations suggests that dominance genetic variance represents a substantial part of genetic variance, and theoretical work predicts that ignoring dominance can inflate estimates of additive genetic variance. Whether this issue is pervasive in natural systems is unknown, because we lack estimates of dominance variance in wild populations obtained in situ. Here, we estimate dominance and additive genetic variance, maternal variance, and other sources of nongenetic variance in eight traits measured in over 9000 wild nestlings linked through a genetically resolved pedigree. We find that dominance variance, when estimable, does not statistically differ from zero and represents a modest amount (2‐36%) of genetic variance. Simulations show that (1) inferences of all variance components for an average trait are unbiased; (2) the power to detect dominance variance is low; (3) ignoring dominance can mildly inflate additive genetic variance and heritability estimates but such inflation becomes substantial when maternal effects are also ignored. These findings hence suggest that dominance is a small source of phenotypic variance in the wild and highlight the importance of proper model construction for accurately estimating evolutionary potential.

中文翻译：

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在野生种群的进化数量遗传分析中可以忽略显性遗传方差吗？

准确估计遗传方差分量对于研究野外进化很重要。对驯化和野生远交种群的实证研究表明，优势遗传方差代表了遗传方差的很大一部分，理论工作预测忽略优势会夸大加性遗传方差的估计值。这个问题在自然系统中是否普遍尚不清楚，因为我们缺乏对原位野生种群优势方差的估计。在这里，我们估计了在 9000 多只野生雏鸟中测量的 8 个性状的优势和加性遗传方差、母本方差和其他非遗传方差来源，这些特征是通过遗传解析的谱系联系起来的。我们发现优势方差，当可估计时，与零没有统计学差异，代表了适度数量 (2-36%) 的遗传变异。模拟表明（1）对平均特征的所有方差分量的推断是无偏的；(2) 检测优势方差的能力低；(3) 忽略优势会轻微地夸大加性遗传方差和遗传力估计，但当母体效应也被忽略时，这种膨胀会变得很大。因此，这些发现表明优势是野外表型变异的一个小来源，并强调了正确构建模型对于准确估计进化潜力的重要性。(3) 忽略优势会轻微地夸大加性遗传方差和遗传力估计，但当母体效应也被忽略时，这种膨胀会变得很大。因此，这些发现表明优势是野外表型变异的一个小来源，并强调了正确构建模型对于准确估计进化潜力的重要性。(3) 忽略优势会轻微地夸大加性遗传方差和遗传力估计，但当母体效应也被忽略时，这种膨胀会变得很大。因此，这些发现表明优势是野外表型变异的一个小来源，并强调了正确构建模型对于准确估计进化潜力的重要性。