Lesbian and heterosexual women respond differently to specific human odours, a brain-scanning study has found. The homosexual women showed similar brain activity to heterosexual men when they inhaled certain chemicals, which may be pheromones, the researchers say.
All clownfish are born male. When they become adults, the largest, most dominant fish becomes a female, and the second largest becomes the breeding male. If the breeding female disappears, the breeding male (now the largest of the group) will become a female, and so on. In other species of tropical fish, when the ratio between males and females becomes imbalanced, dominant females may become males.