An older-brother effect seems to play a role in sexual orientation among

Question

Quizplus · Accepted Answer

The older-brother effect is a phenomenon in which men who have older brothers are more likely to be gay. This effect is thought to be due to the fact that older brothers produce a hormone that masculinizes the brains of their younger brothers in the womb. This hormone exposure makes younger brothers more likely to be interested in men and less likely to be interested in women.

An Older-Brother Effect Seems to Play a Role in Sexual