Secret female contraceptive weapons of female dolphins

Some female dolphins evolve secret genital weapons to avoid conception with unwanted partners.

Researchers at Georgetown University, Washington, USA found that female bottlenose dolphins have special evolution in genital organs to prevent conception with the males they did not want, New Scientist said. through the news.

Bottled dolphins change the genitals to prevent males from fertilizing.(Photo: FLPA).

By technique of tomography, researcher Janet Mann discovered mouse dolphins and female bottlenose dolphins with many folds extending in the genitals, which could prevent the male's penis from entering to conceive.

Male bottlenose dolphins often form an alliance of 2-4 strong pups to prevent competitors from approaching females. When faced with such an alliance, female dolphins have very few options for pairing partners. However, the vaginal fold gives it privilege."It is not possible to choose mating partners, but it is possible to choose which male or female sperm is fertilized or which sperm is more accurate , " Mann said.

In all four species in the study, the ideal location for successful fertilization is the male on the female. This conclusion is consistent with the researchers' observations of natural dolphins and paired dolphin beaks.

The combination of precise posture and complex vaginal structure allows the female to prevent fertilization through small movements during the pairing process. "In terms of behavior, it seems that the females are very passive. But considering the reproductive surgery, we find that they have all the tricks to control motherhood," said Dara Orbach of Dalhousie University. , Canada, said.