Jakarta –
Most mammals remain fertile until the end of their lives. For people who experience it, menopause occurs when the ovaries stop functioning. This biological experience involves a decrease in reproductive hormones such as estrogen and progesterone, which causes symptoms such as hot flashes and brain fog.
In humans, menopause tends to occur between the ages of 45 and 55 years. Menopause was long thought to be an experience unique to humans and some species of toothed whales. But now, a study shows that female chimpanzees also live quite a long time after their ovaries retire.
Wild Chimpanzees Also Menopause
Thanks to 21 years of field studies, the fact that wild chimpanzees also experience menopause has been revealed. Between 1995 and 2016, a group of scientists observed the behavior of a community of chimpanzees living in the dense rainforest of Kibale National Park in Uganda.
During that period, scientists measured the mortality and fertility rates of 185 women in the Ngogo community. The research, published in the journal Science, later revealed that the community’s urine samples also contained varying levels of hormones. Hormone levels are often the main indicator of menopause in humans.
They are between 14 and 67 years old and have different reproductive abilities. The results of this study also show that hormone levels are also a marker of menopause in chimpanzees.
In fact, scientists found that female chimpanzees live about 20 percent of their lives in a post-reproductive state. After the age of 30, chimpanzee fertility begins to decline and scientists have not observed any births to chimpanzee mothers over 50 years old.
Why Can Chimpanzees Menopause?
No one knows why in evolution there was a menopause or why humans experience it, while few other mammals do. One theory regarding this is the “grandmother hypothesis”, namely that women live to help raise their children.
But according to research, chimpanzees are actually bad grandmothers. They often live far from their daughters and do not help raise their grandchildren.
Instead, the researchers speculate that chimpanzees at Ngogo today may enjoy good ecological conditions, including abundant food supplies and low predation rates, meaning they can live longer post-reproduction. This is consistent with the fact that chimpanzees in captivity who receive food and medical care, have lived well beyond their reproductive years.
In contrast, other chimpanzee populations may experience negative impacts from humans such as increased disease, and thus never live long enough to experience menopause.
A conclusive answer to why chimpanzees survive beyond their reproductive years is still a question mark. However, the researchers hope this discovery will help us learn more about the evolution of menopause in humans.
According to evolutionary biologist Prof Michael Cant, who was not involved in this research, he considers this research to explain and raise questions about the evolution of menopause. He added that these findings could change fundamental understanding of human biology and behavior.
Watch the video “5 strange animals resulting from genetic engineering”
(nah/nwk)
2023-10-30 12:00:18
#Research #Wild #Chimpanzees #Experience #Menopause
