First star-forming gas clouds were much denser. (Early Universe was smaller and prior to stellar fusion also had more hydrogen.) Did not most first generation stars leave Black Holes behind when the rapidly completed their life cycle? How much did the universe expanded while the first stars ran their life cycle and typically formed a pair of gravitationaly bound black holes? Did the typical star pair of the second generation also leave a pair of black holes behind when it died? How many generations before the typical star did not leave a black hole behind? How does the number of these early-generation stellar-core black holes compare with the total number of currently luminious stars? Are there enough black holes to account for "dark matter"? I.e. what fraction of the matter that "condensed" from Big Bang energy is now in black holes?