Every entry, in stratigraphic order
The 200 entries of Deep Time, grouped by the unit of the geological time scale they belong to, oldest first.
Hadean11 entries
- The Earth Grew by Collision~4.54 billion years ago
- When the Whole Planet Was Molten~4.5 billion years ago
- The Collision That Made the Moon~4.5–4.4 billion years ago (debated)
- The First Air~4.45 to 4.3 billion years ago
- Where Earth's Water Came From~4.5 to 4.4 billion years ago (origin debated)
- The Oceans Came Early~4.4 billion years ago
- The Gold Came Late~4.4 billion years ago
- Life's Ingredients Fell from the Sky~4.3 billion years ago
- The Ancestor of Everything Alive~4.2 billion years ago (estimates 4.3 to 3.5 Ga)
- Where Life May Have Started~4.2 billion years ago (setting debated)
- One Molecule Doing Two Jobs~4.1 billion years ago (a stage, not a date)
Archean20 entries
- The Oldest Rock You Can Touch~4.03 billion years ago (older claims to 4.3 Ga)
- The Magnetic Shield Switches On~3.9 billion years ago (claims reach 4.2 Ga)
- The Bombardment That May Never Have Happened~3.9 billion years ago (existence disputed)
- The Oldest Traces of Life~3.7 billion years ago (claims 3.95–3.5 Ga)
- The Rust at the Bottom of the Sea~3.5 to 1.8 billion years ago
- Lava Too Hot to Exist Today~3.5 to 2.7 billion years ago
- A Sky Full of Methane~3.5 to 2.4 billion years ago
- The Proof That the Air Had No Oxygen~3.5 to 2.4 billion years ago
- The First Methane Makers~3.46 billion years ago
- The Oldest Reef, Built by Microbes~3.43 billion years ago
- The First Photosynthesis~3.4 billion years ago
- Life Reaches Dry Land~3.22 billion years ago
- Life Pulls Nitrogen Out of the Airat least 3.2 billion years ago
- The First Continents~3.2 to 2.5 billion years ago
- Photosynthesis Learns to Split Water~3.2–2.8 billion years ago
- Plate Tectonics Begins~3 billion years ago (estimates 3.8 to 2.2 Ga)
- The First Ice Age~2.9 billion years ago
- The Greatest Gold Field~2.9 to 2.78 billion years ago
- Oxygen Before the Oxygenation~2.7 to 2.5 billion years ago
- A Contested Whiff of Oxygen~2.5 billion years ago (disputed)
Siderian3 entries
Rhyacian4 entries
Orosirian7 entries
- The Largest Crater on Earth~2.02 billion years ago
- Our Microbial Ancestor~2 billion years ago
- The Nineteen-Hour Day~2 to 1 billion years ago
- How Plants Got Their Chloroplasts~1.9 billion years ago
- The Cell That Swallowed a Bacterium~1.9 billion years ago (order of events debated)
- The Crater That Became a Mine~1.85 billion years ago
- The Iron Stops Settling~1.85 billion years ago
Statherian7 entries
- The First Supercontinent We Can Map~1.8 to 1.4 billion years ago
- The First Complex Cells~2.0–1.8 billion years ago
- The Boring Billion~1.8 to 0.8 billion years ago
- When the Deep Sea Turned Toxic~1.8 to 0.8 billion years ago
- Nature's Nuclear Reactors~1.7 billion years ago
- A Lost World, Read in Its Molecules~1.64 billion to 800 million years ago
- Cells That Stayed Together~1.6 billion years ago
Calymmian3 entries
Stenian4 entries
Tonian4 entries
Cryogenian4 entries
Ediacaran9 entries
- The Layer That Ends a Snowball~635 million years ago
- The First Phosphate Boom~630 to 574 million years ago
- Fossils Caught Mid-Division~609 million years ago
- The Glaciation That Was Not a Snowball~581 to 580 million years ago
- Large Life, Soft and Unarmed~575 to 539 million years ago
- The Largest Carbon Swing Ever Recorded~574 to 567 million years ago
- The First Trails~560 to 539 million years ago
- The End of the Ediacara Biota~550 to 539 million years ago
- The First Skeletons~550 million years ago
Cambrian8 entries
- A Rain of Millimetre Shells~539 to 521 million years ago
- The Cambrian Explosion~540–518 million years ago
- The First Animal Reefs~525 to 510 million years ago
- Animals Learn to Dig~521 to 509 million years ago
- The First Backbones~518 million years ago
- The Window on Soft Bodies~518 to 500 million years ago
- The First Eyes~515 million years ago
- The Teeth That Were Not Ours~515 million years ago
Ordovician4 entries
Silurian3 entries
Devonian12 entries
- Life Leaves the Seafloor~410 to 360 million years ago
- The Shell That Rolled Up~409 to 393 million years ago
- The Partnership Under the Soil~407 million years ago
- A Hot Spring That Petrified a Swamp~407 million years ago
- The Invention of Wood~393 to 383 million years ago
- The Largest Reefs Earth Has Had~390 to 372 million years ago
- Vertebrates Walk onto Land~390 million years ago
- The First Forests~385 million years ago
- Jaws Without Teeth~382 to 358 million years ago
- The Invention of the Seed~372 million years ago
- Late Devonian Extinctions~372 to 359 million years ago
- The Long Ice Age~360 to 260 million years ago
Carboniferous6 entries
- Pangaea~335 to 175 million years ago
- The Age of Giant Insects~330 to 260 million years ago
- Insects Take to the Air~325 million years ago (molecular estimates up to 406 Ma)
- The Amniotic Egg~318 million years ago (tracks suggest ~356 Ma)
- The Line That Leads to Us~315 to 300 million years ago
- The Coal Forests Break Up~305 million years ago
Permian3 entries
Triassic8 entries
- Reptiles Go Back to the Sea~250 to 242 million years ago
- Feathers Before Flight~240 to 160 million years ago
- The Shell Crushers~235 to 66 million years ago
- The Two Million Year Rain~234 to 232 million years ago
- Warm Blood~233 million years ago
- Dinosaurs Start Small~233–230 million years ago
- The First Flying Vertebrates~220 million years ago
- The First Mammals~220–205 million years ago
Jurassic5 entries
Cretaceous8 entries
- The First Flowers~140 million years ago (origin debated)
- How Snakes Lost Their Legs~128 to 95 million years ago
- Bees and Flowers~123 to 100 million years ago
- When the Ocean Ran Out of Oxygen~120 to 94 million years ago
- The Chalk Seas~100 to 66 million years ago
- The Hottest the World Has Been~94 to 83 million years ago
- Dinosaurs in the Dark~80 to 66 million years ago
- The Lava That Shares the Blame~66 million years ago
Paleogene9 entries
- The Asteroid That Ended the Dinosaurs66.0 million years ago
- The Mammals Fill the Gap~66 to 56 million years ago
- The Last Time Carbon Rose This Fast~56 million years ago
- First Primates~55 million years ago
- Flight, Then Sonar~52 million years ago
- Whales Return to the Sea~50 to 38 million years ago
- The Fern That Cooled the Arctic~49 to 48 million years ago
- A Plateau Makes a Monsoon~40 to 10 million years ago
- Antarctica Freezes~34 million years ago
Neogene8 entries
- The Spread of Grasslands~10 to 3 million years ago
- The First of Our Own Branch~7 million years ago
- The Mediterranean Dries Out~5.96 to 5.33 million years ago
- The Largest Animal Ever~4.5 million years ago
- Walking Upright~3.7 to 3.2 million years ago
- Oldest Stone Tools~3.3 million years ago
- The First of Our Genus~2.8 million years ago
- Two Americas Become One~2.8 million years ago (contested)
Quaternary50 entries
- The Ice Ages~2.6 million to 11,700 years ago
- The First Departure~2.1 to 1.8 million years ago
- The Control of Fire~1 million years ago (habitual use by ~400,000 years ago)
- The Small People of Flores~700,000 to 50,000 years ago
- Neanderthals~430,000 to 40,000 years ago
- Homo sapiens Emerges~300,000 years ago
- The Denisovans~300,000 to 50,000 years ago
- The Toba Eruption~74,000 years ago
- The First Sea Crossing~65,000 years ago
- Out of Africa~60,000 years ago
- Ice Age Art~51,000 years ago
- The Megafauna Extinction~50,000 to 4,000 years ago
- The First Domestic Animal~23,000 years ago (estimates 40,000 to 14,000)
- The Last Continent~23,000 to 15,000 years ago (earliest dates disputed)
- The Cold Snap in the Middle of the Thaw~12,900 to 11,700 years ago
- Farming Begins~11,500 years ago
- When the Sahara Was Green~11,000 to 5,500 years ago
- The Coldest Century of the Holocene~8,200 years ago
- Drinking Milk as an Adult~7,500 years ago
- The Black Death1347 to 1352 CE
- The Industrial Revolution1750 to 1950 CE
- No Vestige of a Beginning1788 CE
- The First Vaccine1796 CE
- Naming the Chapters1815 to today
- Descent with Modification1859 CE
- The Rules of Inheritance1866 CE
- The Sixth Extinctionsince about 1900 CE
- Genes Live on Chromosomes1902 to 1915 CE
- The Mould That Killed Bacteria1928 to 1945 CE
- DNA Carries the Message1944 to 1952 CE
- Counting Atoms to Tell Time1949 CE
- The Great Accelerationsince 1950 CE
- The Structure of DNA1953 CE
- Four and a Half Billion Years1956 CE
- Measuring the Air1958 to 2016 CE
- The Genetic Code1961 to 1966 CE
- Reading Time in Proteins1962 to 1965 CE
- The Sea Floor Is a Conveyor1963 to 1968 CE
- Cutting and Pasting Genes1973 CE
- A Third Branch of Life1977 CE
- Reading DNA1977 CE
- A Layer of Iridium1980 CE
- A Species Deliberately Ended1980 CE
- Copying DNA at Will1983 to 1985 CE
- Reading the Dead1984 to 2010 CE
- The Hole We Closed1985 to 2016 CE
- The Human Genome2001 to 2022 CE
- Eight Hundred Thousand Years of Air2004 CE
- CRISPR Genome Editing2012 CE
- The Epoch That Was Refused2024 CE