Scientists: African rats can "seal" their vaginas if they don't want children

Female African hamster rats (Cricetomys gambianus) "seal" their vaginas if they do not want to have offspring. This unusual method of contraception in animals has been studied by scientists.

According to Science Alert, these rats are very intelligent. They can be trained, in particular, to find landmines that need to be defused, sniff out tuberculosis, and so on. However, it turned out that they were extremely infertile.

"We wanted to understand their reproductive behavior and their olfactory abilities because they were very important in humanitarian work," explained behavioral ecologist Alex Ofiri when he first studied Cricetomys gambianus' breeding behavior.

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During the study, the scientist found that the life expectancy of these rats can be eight years, with some females "postponing reproduction" until they are four years old. And some stop breeding after a successful pregnancy.

The researchers say that female rats can "seal" their vaginas at will.

"In this morphological state, females had a smaller uterus and a fused vaginal opening. Moreover, their urine had a significantly different chemical composition than their neighbors with normal vaginal openings, who were actively reproducing," the scientists say.

Cornell University ethnologist Angela Freeman and her colleagues identified 23 transitions in reproductive states in 17 of the 51 female rats they observed. Some of the individuals went through the reproductive state more than once, and when one of the actively reproducing females died of old age, "the vaginas of seven colony members opened."

"From this, we assume that females can suppress the reproduction of others using volatile (pheromone) olfactory signals," the scientists explained.

That is, one female could manipulate other females to stop reproducing, becoming the "dominant reproductive female."

This study was published in Current Biology.

Earlier, we wrote about a rat that helped to clear fields of mines.

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