In order to trace the history and development of anabolic steroids from their beginning to their present day form, we first need to look back towards ancient times, when it was known that the testicles were required for both the development and maintenance of male sexual characteristics. In modernity, this concept was further developed, by a scientist named Berthold and his experiments on cockerels done in 1849. He removed the testes from these birds, and they lost several of the characteristics common to the male of their species, including sexual function. So, we knew as early as 1849 that the testicles functioned to promote what we consider to be primary male sexual properties; in other words, they are what "make men into men". Berthold also found that if the testicles were removed and then transplanted to the abdomen, the sexual function of the birds was largely unaffected. When the birds were dissected, it was found that no nervous connections were formed, but a vastly extensive series of capillarization took place. This provided strong evidence that "the testes act upon the blood" and he further concluded that this blood then had a systemic effect on the entire organism. Anabolic Steroid history, therefore, can be truly said to have made its first step with this simple series of experiments.