Exponental: @op, come again, I dont understand!

anisylva: Why do women go into
menopause? “The ovaries basically shut down,” explains West
Penn Hospital OBGYN Dr. Emily Lebovitz. “Why
exactly that occurs we don’t know.” Around age 50, women end their reproductive
years — an event called menopause. Hormones
change, menstrual cycles stop, and natural
childbearing is no longer a possibility. Menopause could be nature’s way of matching
motherhood to younger bodies. “It’s certainly healthier for them to have children in
their 20s, 30s, 40s, and then it becomes much more
difficult,” Dr. Lebovitz continues. But a Canadian researcher says it’s because of men,
and because of competition. Using computer modeling, he found competition
among men of any age for younger mates left older
females with less chance of reproducing. He says the result is that genes favoring
menopause got passed down through the
generations, so that now it’s a normal part of the
female genetic blueprint. But there are problems with this theory. “That’s an assumption that they made when they
started their computer model, that men do like
younger mates, and I don’t think you can make
that assumption,” says Dr. Lebovitz. What’s more, if menopause is genetically
determined and influenced by the environment,
you would expect that some women would not go
through menopause, or with increased life
expectancy, the length of fertility might
proportionally lengthen. But that hasn’t been the case. “We haven’t seen a change in the age of
menopause in general. It’s somewhat preposterous
to assume this has to do with men’s choices,” Dr.
Lebovitz says. “Computer studies are difficult.
Certainly population based studies can have more
validity.”