Cricetomys gambianus or African giant rats fascinate with their intelligence. These large rodents are so smart that they have helped save lives on several occasions. Some were specially trained Defuse landmines or track down tuberculosis. Others have learned to carry small backpacks to rescue people in disaster areas.
Unfortunately these intelligent mammals are not productive. Breeders are desperate for more breeding females because there is not enough supply to meet demand. And yet other rodents are known for their ability to breed wildly.
Fascinated, Alex Ophir, behavioral ecologist, leaned over the reproductive behavior of this kind in 2019.
Female giant rats seal their vaginas to stop reproduction
In reality, Cricetomys is gambianus closer to the hamster than the rat. This animal is about one meter long from the mustache to the end of the tail and can live up to eight years. To the great surprise of breeders, however, many females do not breed until they are four years old. Worse, some of them Stop after a successful pregnancy.
Photo credit: BBC
Baffled by this phenomenon, researchers took a closer look. They discovered that many women just didn’t have gave up having more children, but that they had literally closed their vaginas. Scientists believe that it is a hormonal manipulation of dominant females so that once they are sterilized, the others take care of them.
Nonbreeders reopen their vaginas when the dominant dies
Significant changes occur in female Cricetomys that have ceased reproduction. In this particular morphological state, their The uterus has shrunk and its vaginal opening has grown together. In addition, the chemical composition of their urine differs from that of their breeding-active conspecifics. The researchers also found that this phenomenon is reversible.
Ethologist Angela Freeman and her colleagues at Cornell University counted as many as 23 transitions in 17 female rats. Even if one of the active breeding bitches died of old age, the vaginas of the other members of the colony have opened. Keep in mind that other mammals also have hormone-modulated reproduction, such as B. those whose reproduction is seasonal.
SOURCE: SCIENCE ALERT