Mommy gene may explain birth rate

ScienceDaily: Mommy gene may explain birth rate: "'...The drive to leave a legacy through offspring can be side-tracked by an attraction to legacy through other things like career, fame, and fortune -- distractions that, until recently, were only widely available to men,' he said. He speculates the trend will eventually subside because over time genetic traits influencing women away from motherhood will necessarily be 'bred out.'"