processes that involve organisms from different generations take place over a period of at least 1 to many generations
biogenesis is generation. metagenesis is alternation_of_generations. parental_generation is strain. degeneration is process. grandfather is direct_relative_two_generations_past. astrology has roots_in_prehistoric_times thelygeny is monogeny. arrhenogeny is monogeny. generation is reproduction. generation is time_period.