Only humans and two species of whale experiences menopause, and its purpose largely remains a mystery. Reproducing and passing on genes is such a large part of evolution that it seems strange for women to spend a significant portion of their lives unable to do so.
Theories regarding the positive impacts of the human menopause include the "mother hypothesis," which states that older women have a much higher chance of dying during childbirth, and the "grandmother hypothesis," which argues that there is a survival benefit when older generations help take care of their children's offspring. More recently, researchers proposed the "conflict hypothesis," which suggests that unrelated women across generations—mothers- and daughters-in-law—compete for resources when they have children at the same time. Because both women’s children would suffer in this situation, there would be a multi-generational benefit if the grandmother could not produce her own children any more.
These hypotheses were ...