2007-01-30 12:59:26 · 3 answers · asked by grumpycandy_0 1 in Science & Mathematics ➔ Biology
The person above is right as to why it is about 50/50, but the reason for more males being born is not correct. it is actually due to the fact that males die more often (for various reasons) up until age 25, after which males and females are about 50/50 again. Evolution has compensated for this by making slightyl more males be born!
2007-01-30 13:39:29 · answer #1 · answered by Anonymous · 0⤊ 0⤋
According to the CDC, the difference is not 5%, it is .05% more males than females. The reason that the proportion of males to females is about the same goes back to genetics. Men have an x chromosome and a y chromosome to give away to determine the sex of a child, and since half of his sperm carry the x (girl) and half carry they y (boy), we have almost a 50/50 proportion of males to females.
A possible explanation of why males have a slightly higher birth rate than girls is that scientists have found that sperm that will create a boy ( the y carrying sperm) are slightly faster swimming than x carrying sperm, so they win the race to the egg slightly more often. (However, the sperm carrying the x chromosome have more endurance!)
2007-01-30 13:22:54 · answer #2 · answered by bio rocks! 3 · 0⤊ 0⤋
Actually... That's not True... There are more females born (about 55%) then males. 5% is a rather large difference.
2007-01-30 13:07:07 · answer #3 · answered by Andrew L 2 · 0⤊ 0⤋