Body Harvest/Fridge

Fridge Logic

 * The aliens cloned The Man In Black from a drop of Adam Drake's blood, which they are shown to acquire in the opening video, set in 2016. The Man In Black then leads the aliens' ground forces in past eras. The aliens are never shown to possess the same time travel abilities that the humans do, so how did The Man In Black even exist before the aliens found the blood?
 * Reverse genetic memory?