Basal metabolic rate can evolve independently of morphological and behavioural traits

Quantitative genetic analyses of basal metabolic rate (BMR) can inform us about the evolvability of the trait by providing estimates of heritability but also of genetic correlations with other traits that may constrain the ability of BMR to respond to selection. Here we studied a captive population of zebra finches (Taeniopygia guttata) in which selection lines for male courtship rate have been established. We measure BMR in these lines to see whether selection on male sexual activity would change BMR as a potentially correlated trait. We find that the genetic correlation between courtship rate and BMR is practically zero, indicating that the two traits can evolve independently of each other. Interestingly, we find that the heritability of BMR in our population (h^2=0.45) is markedly higher than was previously reported for a captive zebra finch population from Norway. A comparison of the two studies shows that additive genetic variance in BMR has been largely depleted in the Norwegian p...

基础代谢率（BMR）的数量遗传学分析不仅能通过估算遗传力（heritability），还能通过估算其与其他可能限制BMR响应选择能力的性状间的遗传相关（genetic correlation），来揭示该性状的可进化性（evolvability）。本研究以已建立雄性求偶率选择系（selection lines）的圈养斑胸草雀（Taeniopygia guttata）种群为对象，测定了这些品系的BMR，以探究针对雄性性行为的选择是否会改变作为潜在相关性状的BMR。结果显示，求偶率与BMR之间的遗传相关几乎为零，表明这两个性状可独立进化。有趣的是，本研究种群中BMR的遗传力（h²=0.45）显著高于此前报道的挪威圈养斑胸草雀种群。两项研究的对比表明，挪威种群中BMR的加性遗传方差（additive genetic variance）已大幅耗尽……