The competition of the sperm and ensuring the subsistence of the species seem to be decisive so that, in certain situations, men ejaculate a greater quantity of semen and that it also has greater motility and speed. This has been witnessed by the latest study carried out by the University of Florida, The College of Wooster and the Center for Reproductive Medicine at the Cleveland Clinic (USA), which shows that when men have sexual relations with a Different woman, for the first time, her ejaculation is more intense, faster and of better quality .
For the experiment, the scientists involved 2 3 heterosexual men between the ages of 18 and 23 . Each of them had to masturbate in each session with a specific pornographic film. The volunteers provided 7 semen samples over the course of 15 days. 6 of the 7 films they viewed were starred by the same actress and only one of them featured a different actress.
The results revealed that the amount of semen each of the men produced increased substantially when exposed to the film with the new actress , demonstrating that sperm competition also exists within the human race. According to experts, to ensure the subsistence of the species, men ejaculate in greater quantities when they meet a ‘new’ woman, as there is an increase in the chances of offspring.
That is, throughout the experiment, no difference was observed between the first and sixth ejaculation; however, the volume and total sperm count increased considerably when a different woman appeared – in this case in the movie with explicit sex. Furthermore, the ejaculation time also decreased significantly .
The study has been published in the journal Evolutionary Psychological Science .
