Biology's Big Bang: The Cambrian Explosion

Picked one by one from a mixed channel. Transcript check: both title readers certain; 3 of 5 sampled certain picks confirmed by transcript, none failed. Channel rule: Include only the expert-interview episodes with descriptive titles that explain a specific historical, archaeological or paleontological topic. Exclude any title using 'Shocking' or similar hooks, film/TV verdicts, 'VS/battle' debate framing, and episodes built around historical-fiction authors rather than scholars.