Chapter 077
Brazilichthys: the 280-million-year-old fish with jaw holes
Brazilichthys, a fish from about 280 million years ago, could shut its mouth only because its upper jaw made room for its fangs.
An animated history of Earth
4.54 billion years, told one layer at a time.
Strata is the whole story of this planet, 366 chapters sited and counting — a new story every day, cut entirely from paper. It starts with a cloud of dust and ends with you.
366 chapters sited13 arcsOne every day
The latest chapter
Its lower fangs slid into holes in its upper jaw.
Latest chapters
Newest layers first.
Chapter 076
White Sands: Dunes Made From 280-Million-Year-Old Gypsum
Chapter 075
Mesosaurus: a 278-million-year-old embryo inside its mother
Chapter 074
Prehistoric Trackways: 280-million-year-old prints like a baby's hand
Chapter 073
Hallett Cove: a boulder a glacier carried more than 50 km
Chapter 072
Gaiasia: a giant hunter longer than a person, 280 million years old
Chapter 071
Pollen fossil insects: the oldest found, 280 million years old
Coming up · not out yet
- Tshekardocoleus
The dig plan
Thirteen arcs, read like a core sample.
The youngest rock always sits on top — so the story is told from the bottom up. Tap a layer to see what’s buried in it.
4.57 – 4.40 billion years ago
Birth of a Planet
Accretion, Theia, and the making of the Moon.
- Tent-pole
- The Theia impact
- Span
- 4.57 – 4.40 billion years ago
A chapter from this layer: “Theia — the day Earth had a twin, and ate it”
The clock we tell time by
If Earth’s history were one year
Every chapter stamps its date on the Earth Calendar: the planet’s 4.54 billion years mapped onto a single year. January crawls. December sprints.
Jan 1
Earth forms
A cloud of dust collapses into a planet.
Feb 21
First life
Chemistry becomes biology in the early oceans.
Jun 21
The air turns to poison
The Great Oxidation Event rusts the oceans.
Nov 18
The Cambrian explosion
Eyes, armor, hunters — animals arrive.
Dec 26
The dinosaurs die
An asteroid ends a 175-million-year reign.
Dec 31, 11:59:37 PM
All recorded history
Everything ever written happens in the last 23 seconds.
A whole planet’s past. One calendar year.
Earth forms on January 1. Each day on this calendar covers about 12.4 million years. The pins below mark positions stated in the published chapters.
Some chapters pause the Clock to follow a clue. A pin can mark the age of a rock even when the event is still hard to date. Choose a month and see what turns up.
Before January 1Chapter 001Chapter 002Chapter 003
A red pin marks a chapter position. Empty months have no published pin here.
January
- January 4Chapter 004 · Theia - the day Earth had a twin, and ate it
The closing narration reaches this day. It does not date the proposed collision to this day.
- January 4Chapter 005 · The Moon - it saved Earth before life existed
- January 5Chapter 006 · The Second Moon - it may still be up there, splattered across the far side
- January 5Chapter 007 · Earth - why didn't a planet built from collisions just stay molten?
- January 11Chapter 008 · The Core: What Is Inside the Earth, All the Way Down
- January 11Chapter 009 · Zircon - the oldest thing on Earth is smaller than a grain of sand
- January 12Chapter 010 · The First Rain - Earth's entire ocean fell out of the sky
- January 13Chapter 011 · The Water - Earth was born too dry
- January 13Chapter 012 · The Late Heavy Bombardment - the apocalypse that may never have happened
The chapter opens here. Its debated impact spike has no confirmed calendar pin.
Meet the cast
The character cabinet
Meet the worlds that crashed and the cells that kept going. Each portrait opens a story, with clues you can find in rock or living things.
Community
Dig with us.
Watch it layer by layer
A new chapter lands every day on YouTube, with cuts for every other platform you already live on.
Steer the dig
When a chapter strikes something you love, we stop and dig deeper — the comments literally reroute the plan.
Keep us honest
Spot an error? Say so. Corrections are credited in the next chapter’s notes.
