Thursday, October 31, 2013
The ratio of women to men decreases as the population ages.
According to the book, “Gender Gap: The Biology of Male-Female Differences” by David Barash and Judith Eve Lipton, worldwide there are approximately 107 baby boys born for every 100 baby girls.
But all human embryos actually start out as females for the first six weeks of life.
After that sixth week of development, if the embryo is male, a certain gene on the Y chromosome will begin to produce androgens that encourage the development of male characteristics.
Men have a life expectancy of 64.52 years, as compared to a life expectancy of 68.76 for women, says information from The Harvard Medical School.
Also, male babies are 25 percent more likely to die in infancy than female babies.