An interesting finding is the fraternal birth order effect. The more older brothers you have, the more likely you are to be homosexual (for men). Seems to indic

An interesting finding is the fraternal birth order effect. The more older brothers you have, the more likely you are to be homosexual (for men). Seems to indicate in-utero mechanisms are involved. https://en.wikipedia.org/wiki/Fraternal_birth_order_and_male_sexual_orientation https://en.wikipedia.org/wiki/Fraternal_birth_order_and_male...