Maternal investment during egg laying and offspring sex: an experimental study of zebra finches
Maternal investment during egg laying and offspring sex: an experimental study of zebra finches
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产卵和后代性交过程中的母亲投资：斑胸草雀的实验研究
DOI：
10.1006/anbe.2002.1973
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发表时间：
2002
期刊：
影响因子：
2.5
通讯作者：
M. Cichoń
中科院分区：
文献类型：
--
作者：
J. Rutkowska;M. Cichoń
为了研究后代的性别是否与投放在卵上的资源数量有关，我们在斑马雀上进行了一项实验。通过操纵它们的食物供应，我们迫使两组雌性增加或减少对后续卵子的投资。由于斑马雀是两性二态的，雌性的生殖价值可能会随着母亲的营养状况而变化，我们预测雌性斑雀会根据卵子的质量来调整后代的性别。雌性在产卵前7周吃劣质食物，然后在产下第一个蛋后再吃补充蛋白质的食物，这会显著增加随后产卵的质量。在产卵前获得高质量食物并在开始产卵后经历食物变质的雌性中，卵质量随产卵顺序的增加不那么明显。在后一组中，产子在后续卵中的比例趋于增加(尽管这略显着)，但与另一组中的产卵顺序无关：这些模式在两组之间存在显着差异。仔鸡的性别与蛋重无关，但初孵化的公鸡比母鸡重。此外，雄卵的孵化成功率低于雌卵。我们认为，雌雄不同的孵化成功率和孵化时质量的性别差异可能是影响孵化性别比的重要因素。
To study whether offspring sex is related to the amount of resources invested in eggs we performed an experiment on zebra finches, Taeniopygia guttata. By manipulating their food supply, we forced two groups of females either to increase or to decrease investment in subsequent eggs. Since zebra finches are sexually dimorphic and the reproductive value of the sexes may vary with maternal nutritional status, we predicted that females would adjust the sex of their offspring to egg quality. Females that received poor-quality food for 7 weeks before egg laying, then food supplemented with proteins after they laid the first egg, significantly increased the mass of subsequent eggs. An increase of egg mass with laying sequence was less pronounced in females that received high-quality food before laying and experienced food deterioration after starting to lay. The proportion of sons in subsequent eggs tended to increase in the latter group (although this was marginally significant) but was not related to laying sequence in the other group: these patterns differed significantly between the groups. Offspring sex was not related to egg mass, but newly hatched male chicks were heavier than female chicks. Furthermore, the hatching success of male eggs was lower than that of female eggs. We suggest that differential hatching success of the sexes and sex differences in mass at hatching may constitute important factors shaping brood sex ratios.