Corrected entry: Note: Spoiler. The "good" race is said to be dying, while the "evil" race is flourishing. As the ending makes clear, each individual of each race is really half of one split individual. Thus, there must at all times be precisely the same number of individuals in each race.
CC
15th May 2004
Correction: Flourishing here seems to mean wealthy as opposed to population numbers. The "bad" race (Skeksis) were using the life force of other creatures in order to maintain their lives. There were no children shown of either race shown. This is not a mistake. Both races were dying. Did you see any children Mystics or Skekses? Also, the crystal had to be "healed" by the time of the great conjunction. It is possible that if it weren't healed, that the personalities would be separated permanently and therefore the Mystics would die and the Skekses would flourish.
Nikki