A new study published in the Journal of Sexual Medicine shows that men who have long term sex with animals are more likely to develop penis cancer. Scientist believe that the long-term sex with animals could produce micro-traumas in the human penile tissue. One researcher stated “the genital mucus membranes of animals could have different characteristics from human genitalia, and the animals’ secretions are probably different from human fluids. Perhaps animal tissues are less soft than ours, and non-human secretions would be toxic for us.”