Female exposure to androstenol increases the number and depth of female interactions with males.
Human females exposed to 5a-16-androsten-3a-ol (androstenol) overnight interact more with males than unexposed females do. The experimental procedure involved having students wear overnight a necklace designed to release androstenol. Next morning the subjects filled in a questionnaire regarding who they had interacted with (i.e. who they had spoken with, including greetings), who initiated the interaction, and the depth of the interaction ("i.e. the extent to which he/she felt the exchange encompassed personal involvement."). No effect was found for males, or for female interaction with females, but the females reported a significant increase in interactions with males.
While some human hairs can be argued to serve various purposes, such as protecting the head from the sun, or sexual signaling, or reducing friction during sex (pubic hairs), the underarm hairs are not located to keep us warm, nor to protect us from the sun, or even to be visible at a distance. The only plausible purpose appears to emit odors or pheromones. . . . Humans do appear designed to receive pheromones, since they have functioning odor detection and apparently functioning vomeronasal systems
The observed behavioral response is probably a mechanism for promoting bonding with mates, and evaluation of potential mates. Recognizing an evolutionary purpose for the female reaction to androstenol makes one feel more confident that the observed effects are real.


Click Here to read the entire article...