Earth’s Prehistoric Oceans Were Almost Unbelievable

A calm documentary for sleep through Earth's prehistoric oceans, from the first animals with eyes to the last great sea reptiles. A sea as hot as a bath, a reptile perhaps the length of a blue whale, and why those oceans still unsettle us. This is a slow, chronological descent through the oceans of the deep past, from the Cambrian, about 539 million years ago, to the asteroid that closed the Cretaceous. Along the way we meet Anomalocaris, straight-shelled giants the length of a canoe, the bladed jaws of Dunkleosteus, the spiral teeth of Helicoprion, ichthyosaurs, plesiosaurs and mosasaurs, and the plankton that fed them all. Five mass extinctions, each with a different cause, shape the journey. It's built on current research, with the uncertain parts marked as uncertain, and the narration stays quiet and unhurried, so you can follow every detail or drift off along the way. 00:00 — Half a Billion Years of Dangerous Seas 05:34 — The Sea Learns to See 15:06 — Into the Open Water 24:04 — Ice, Then the First Jaws 32:49 — Blades, Hearts and Mothers 41:29 — Older Than the Trees 49:53 — Spiral Teeth and Sea-Lily Gardens 59:53 — The Great Dying 1:08:06 — Reptiles Return to the Sea 1:16:24 — Giants Before the Rift 1:23:32 — Eyes Wider Than a Hand 1:31:41 — Four Flippers and a Giant Fish 1:41:23 — The Chalk Sea 1:50:55 — What the Ocean Kept SELECTED SOURCES Vermeij (1977), Paleobiology — the Mesozoic Marine Revolution and the escalation between predators and prey Paterson et al. (2011), Nature — the compound eyes of Anomalocaris Sun et al. (2012), Science — lethally hot seas after the end-Permian extinction Lomax et al. (2024), PLOS ONE — Ichthyotitan, a giant ichthyosaur from the end of the Triassic Natural History Museum, London — Mary Anning's ichthyosaur and plesiosaur Silence of the Earth makes slow, calm documentaries about deep time. If this one kept you company, consider subscribing.