The result of his experiment: the rooster's morning crow was over. At the time, Berthold did not know which substance in the rooster's testicles might be involved – we now know that it is the sex ...

Testosterone, a hormone commonly associated with male reproductive health ... The focus of future research is on refining our ...

“it’s a lot to pin on a simple molecule” which in fact, is: “neither the biological essence of manliness nor even ‘the male ...

At the time, Berthold did not know which substance in the rooster's testicles might be involved—we now know that it is the sex hormone testosterone. Although testosterone is also present in ...