Data from: Effects of individual-based preferences for colour-banded mates on sex allocation in zebra finches

Sex allocation theory predicts that females mated to attractive males produce more sons than females mated to unattractive males. However, previous tests of this hypothesis have obtained mixed results. We suggest that females differ in the traits they find attractive. To test this proposition, we assessed female zebra finches' preferences for males banded with red or green plastic leg bands and then tested the sex allocation pattern of females paired with preferred and non-preferred males. Although most females preferred red-banded males, 34% of females consistently preferred green-banded males. The sex ratio at laying and hatching was not influenced by paternal preferred status. However, the fledging sex ratios differed between females paired with preferred and non-preferred males due to sex-biased chick mortality; sons of females paired with preferred males were born heavier and were more likely to survive than daughters. Our results indicate that female zebra finches show individual variation in their preferences for colour banded males, although females do not seem to adjust the offspring sex ratio in response to their mate's band colour. However, the differential post-hatch mortality suggests females may differentially allocate resources into male and female eggs according to their individual mate preferences.性分配理论（Sex Allocation Theory）预测：与具有吸引力的雄性交配的雌性，其产下的雄性后代比例高于与无吸引力雄性交配的雌性。然而，此前针对该假说的验证实验得到了混杂不一的结果。我们提出，雌性对雄性吸引力的评判性状存在个体差异。为验证这一命题，我们首先评估了雌性斑胸草雀（zebra finches）对佩戴红色或绿色塑料腿环的雄性的偏好，随后检验了与偏好雄性、非偏好雄性配对的雌性的性分配模式。尽管多数雌性更偏好佩戴红色腿环的雄性，但仍有34%的雌性始终偏好佩戴绿色腿环的雄性。产卵及孵化阶段的性比并未受父本是否为雌性偏好个体的影响。然而，由于雏鸟存在性偏向的死亡率，与偏好雄性、非偏好雄性配对的雌性的出飞期性比存在显著差异：与偏好雄性配对的雌性所产的雄性幼雏出生时体重更大，且存活率高于雌性幼雏。我们的研究结果表明，雌性斑胸草雀对佩戴彩色腿环的雄性的偏好存在个体差异，尽管雌性似乎并不会根据配偶的腿环颜色调整后代性比。不过，孵化后存在的差异化死亡率表明，雌性或可根据自身对配偶的个体偏好，对雄性和雌性卵分配差异化的资源。