The Cambrian Explosion
Days 29–56 cover the sudden proliferation of complex animal life — the Cambrian explosion — when the seas filled with the ancestors of every major animal body plan alive today: trilobites, the strange creatures of the Burgess Shale, and the first nervous systems.
גדי has 28 days and covers days 29–56 of the Gaian year · Gaiad chapters 29–56.