You start where the story starts: with Ivanov's first hybrid experiments at Askania-Nova. Every correct answer carries you deeper into the archive of Soviet biomedical ambition. Answer them all and you reach the Bion space monkeys, the strange last flowering of the primate station Ivanov's contemporaries founded.
Wrong answer? You fall back to the last experiment you passed on the ladder. Three 50:50 jokers and two skips are in your desk drawer, comrade.