Research reveals that male masturbation has evolved from 40 million years ago to wash away pathogens from the reproductive tract



Masturbation is a common behavior throughout the animal kingdom, including cats, dogs, dolphins, and horses, but it has been observed as a prominent behavior, especially in primates, including humans. Masturbation was thought to be a pathological or sexually arousing behavior, but little research has been done on its evolutionary history or significance. However, a research team led by Matilda Brindle, an anthropologist at University College London, said, ``Masturbation in primates is a characteristic behavior that has continued since ancient times, increasing reproductive success and preventing sexually transmitted diseases. There is a possibility of preventing it, ”the research result was announced.

The evolution of masturbation is associated with postcopulatory selection and pathogen avoidance in primates | Proceedings of the Royal Society B: Biological Sciences

https://doi.org/10.1098/rspb.2023.0061



Study explains the evolutionary origins and advantages of masturbation

https://phys.org/news/2023-06-evolutionary-advantages-masturbation.html

Masturbation May Actually Protect Against Pathogens. Here's Why. : ScienceAlert
https://www.sciencealert.com/masturbation-may-actually-protect-against-pathogens-heres-why

Jacking Off Has Evolutionary Benefits Going Back 40 Million Years, Study Says
https://www.vice.com/en/article/qjvvjx/jacking-off-has-evolutionary-benefits-going-back-40-million-years-study-says

Brindle et al.'s research team said, ``There are few systematic conventional comparative studies on masturbation, and its evolutionary history is unknown,'' and in order to eliminate this gap, primate masturbation The analysis included 246 academic papers and 150 survey results from primatologists and primate keepers. As a result of the analysis, it was revealed that ``masturbation in primates has a remarkable frequency of male masturbation in species where females mate with multiple males.'' The research team reported that ``the frequency of masturbation decreased significantly in species where females mate with a single male, but no decrease in frequency was observed in species where females mate with multiple males.'' .

Therefore, the research team's discovery that masturbation is patterned rather than accidental suggests the possibility that masturbation is not just for sexual pleasure.

The research team also used comparative methods in phylogeny to analyze the evolutionary pathway of masturbation in primates over time. As a result of the survey, masturbation has a long evolutionary history among primates, and masturbation in apes has become common since the ancestors of primates diverged into monkeys such as tarsiers and apes 40 million years ago. It has been suggested that there is a possibility that We also found that masturbation in primates may have evolved since then.



Brindle et al. List two types of benefits for the seemingly meaningless act of masturbation: the ``post-mating selection hypothesis'' and the ``pathogen avoidance hypothesis''.

The `` post-copulatory selection hypothesis '' raises the possibility that male primates masturbate in preparation for mating with females, so that higher quality sperm can be used during mating. In addition,

previous research suggests that masturbating may increase the probability of fertilization by expelling old sperm in advance and ejaculating new sperm during mating with an actual female. I'm here. According to the research team, male masturbation may have evolved in competition with other males over females.

The 'pathogen avoidance hypothesis' is a hypothesis that masturbating can cleanse the urethra, which is the site of infection for many sexually transmitted diseases. Masturbating ejaculation has been shown to reduce the risk of sexually transmitted infections after mating with a female by flushing pathogens that cause sexually transmitted diseases from the reproductive tract. ``In the absence of pathogens that lead to sexually transmitted diseases, the frequency of masturbation decreased at a very high rate, whereas in the presence of pathogens, the frequency of masturbation did not decrease.'' said.

On the other hand, the research team reported that the importance of female masturbation was not clear due to the small number of reports, and the research team said, ``In order to clearly understand the evolutionary role of female masturbation, it is necessary to understand female sexuality. We need more data on behavior.'



``Our findings shed light on the history and function of masturbation, a common but poorly understood behavior, and produced important findings in our understanding of masturbation,'' said Brindle. The fact that masturbation has been observed in many primates, both wild and captive, indicates that masturbation is not just for recreational purposes and is part of a healthy, wholesome sexual repertoire. ' said.

Brindle also argues that ``primates may masturbate as needed, depending on the complex situation they find themselves in.''

in Science, Posted by log1r_ut