In the study, scientists measured the IQ of 2500 brothers and sisters and they found an uneven number of men not only in the top two percent, but also in the bottom two percent.

• 科学家共对2500名男女进行了智商测验。结果发现，男性的智商水平分布极不平衡，得分最高的2%25和最低的2%25都是男性。