Why Does Pregnancy Last 9 Months?

If human newborns came out as fully developed as chimp babies, human pregnancy would have to last at least twice as long. In a new theory, researchers argue that how much energy mothers can spare is the key factor in how long pregnancy lasts.

Source: http://www.npr.org/blogs/health/2012/08/28/160174038/why-does-pregnancy-last-9-months?ft=1&f=1007

new orleans saints mark sanchez tebow jets new york jets