Hormones In The Darkness

After John Hunter, it wasn't until over 50 years later that there was a substantial advancement in the area of hormones. Keep in mind that at this point, the discovery of the concept of hormones were still not yet uncovered and that scientists across all around the world were still in the dark about this subject matter.

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In 1849, a man by the name of Arnold Berthold followed suit with John Hunter's previous experiments and made some new discoveries of his own.

Arnold castrated roosters as well but this time, he returned a testicle back into the body cavity of the corresponding castrated rooster. This led to the rooster showing normal sexual behavior and comb development. As a conclusion, the result was that the testes must have released something into the blood of the rooster. Now today, as we know, the consequence that was seen through this experiment was the responsibility of hormones.