The Trivers-Willard hypothesis (TWH) states that individuals in good condition favor offspring of the sex that has a higher variance in reproductive value. Empirical studies with historical human populations suggest that the TWH might explain biased birth-ratios as well as biased parental investment in male or female offspring. However, empirical tests of the TWH in modern human populations are less conclusive.

In this study, we investigate whether parental investment in education might be skewed according to the TWH in an African sample (N = 314) that includes students from 8 different countries. The data show that male students who rate their family’s wealth high tend to report more parental involvement in their own education, whereas the opposite is true for female students. This pattern is in accordance with the TWH for parental investment. The results support the validity of evolutionary explanations of behavioral bias in the context of parental investment in offspring education.

特里弗斯-威拉德假说 (TWH) 指出，状况良好的个体更青睐生殖价值差异较大的性别的后代。对历史人口的实证研究表明，TWH 可以解释出生率的偏差以及父母对男性或女性后代的投资的偏差。然而，对现代人群 TWH 的实证检验还没有那么结论性。

在这项研究中，我们根据非洲样本 ( N  = 314) 的 TWH 调查父母对教育的投资是否可能出现偏差，该样本包括来自 8 个不同国家的学生。数据显示，对家庭财富评价较高的男学生往往表示父母更多地参与自己的教育，而女学生则相反。这种模式符合父母投资的TWH。结果支持了在父母对后代教育投资的背景下行为偏差的进化解释的有效性。