A closer look at the fertility behavior of the poor is important because of the extensive literature on the "replacement effect" of high infant mortality.
When professionals were going through the footage they had collected on John F. Kennedy’s assassination, they found an unknown woman lurking in the shadows with a camera in front of her face.
He did this by having them watch movie clips that either invoked happy or sad emotions, and asking them to dwell on positive or negative aspects of their own lives.
Closer examination revealed the two hull sections had split exactly where the ship broke in two, making them a possible key to the mystery of the ship's final moments.
Inheritors of some of the viewpoints of early twentieth-century Progressive historians such as Beard and Becker, these recent historians have put forward arguments that deserve evaluation.