Females in a variety of taxa adjust offspring sex ratios to prevailing ecological conditions. However, little is known about whether conditions experienced during a female’s early ontogeny influence the sex ratio of her offspring. We tested for past and present ecological predictors of offspring sex ratios among known-age females that were produced as offspring and bred as adults in a population of house wrens. The body condition of offspring that a female produced and the proportion of her offspring that were male were negatively correlated with the size of the brood in which she herself was reared. The proportion of sons within broods was negatively correlated with maternal hatching date, and varied positively with the quality of a female’s current breeding territory as predicted. However, females producing relatively more sons than daughters were less likely to return to breed in the population the following year. Although correlative, our results suggest that the rearing environment can have enduring effects on later maternal investment and sex allocation. Moreover, the overproduction of sons relative to daughters may increase costs to a female’s residual reproductive value, constraining the extent to which sons might be produced in high-quality breeding conditions. Sex allocation in birds remains a contentious subject, largely because effects on offspring sex ratios are small. Our results suggest that offspring sex ratios are shaped by various processes and trade-offs that act throughout the female life history and ultimately reduce the extent of sex-ratio adjustment relative to classic theoretical predictions.

中文翻译：

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产妇的出生环境和繁殖地区可预测后代的状况和性别比。

各种分类单元中的雌性会根据当前的生态条件调整后代性别比例。然而，关于雌性早期发育过程中所经历的状况是否影响其后代的性别比例知之甚少。我们测试了过去和现在关于已知年龄的雌性的性别预测指标，这些雌性是在一群w中作为后代生产并成年后繁殖的。雌性产生的后代的身体状况和雄性的后代比例与她自己所饲养的育雏尺寸负相关。如所预期的，育雏中的儿子比例与母体孵化日期呈负相关，与母本育种区域的质量呈正相关。然而，第二年，育有较儿子多于女儿的雌性，较不可能再繁殖。尽管是相关的，但我们的结果表明，饲养环境可以对以后的孕产妇投资和性别分配产生持久的影响。此外，儿子相对于女儿的过度生产可能会增加女性剩余生殖价值的成本，从而限制了在高质量育种条件下儿子的繁殖程度。鸟类的性别分配仍然是一个有争议的话题，主要是因为对后代性别比例的影响很小。我们的研究结果表明，后代性别比例是由贯穿整个女性生活史的各种过程和权衡决定的，相对于经典的理论预测而言，最终减少了性别比例调整的程度。