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Absolutely! Let’s make a comprehensive timeline table of life on Earth based on The Wonder of Life on Earth, including major evolutionary milestones and all the recognized mass extinctions. I’ll combine geologic time, key life forms, and mass extinction events so it’s clear and educational.
🌍 Timeline of Life on Earth with Mass Extinctions
| Time (Million Years Ago) | Key Evolutionary Events & Life Forms | Mass Extinction Events |
|---|---|---|
| 4600–4000 MYA | Formation of Earth; cooling crust; first oceans form | — |
| 4000–3500 MYA | First chemical systems → first primitive life (prokaryotes) | — |
| 3500–2500 MYA | Photosynthesis evolves → oxygen begins to accumulate | — |
| 2500–2000 MYA | Great Oxidation Event; first eukaryotes (cells with nuclei) | — |
| 1200–800 MYA | Multicellular life appears | — |
| 600–541 MYA | Ediacaran biota: soft-bodied multicellular organisms | — |
| 541 MYA | Cambrian Explosion – rapid diversification of marine life | — |
| 485 MYA | First land plants appear | — |
| 444 MYA | Ordovician-Silurian Extinction (~85% species lost) | Mass Extinction #1 |
| 419–359 MYA | First jawed fishes, insects; first forests | — |
| 359 MYA | Late Devonian Extinction (~75% species lost) | Mass Extinction #2 |
| 359–252 MYA | Amniotes evolve; first reptiles; Pangaea forms | — |
| 252 MYA | Permian-Triassic Extinction (~96% species lost, “The Great Dying”) | Mass Extinction #3 |
| 252–201 MYA | Rise of reptiles, early dinosaurs, first mammals | — |
| 201 MYA | Triassic-Jurassic Extinction (~80% species lost) | Mass Extinction #4 |
| 201–145 MYA | Dinosaurs dominate; first birds | — |
| 145–66 MYA | Flowering plants diversify; marine reptiles abundant | — |
| 66 MYA | Cretaceous-Paleogene Extinction (~75% species lost; dinosaurs extinct) | Mass Extinction #5 |
| 66–23 MYA | Mammals diversify; primates evolve | — |
| 23–2.6 MYA | Early hominins appear; grasses spread; modern continents form | — |
| 2.6 MYA–12,000 YA | Ice ages; evolution of Homo sapiens; agriculture emerges | — |
| 12,000 YA–Present | Human civilizations; industrialization; climate impact | Anthropocene/modern biodiversity crisis (sometimes called a 6th mass extinction) |
✅ Notes on Mass Extinctions
Ordovician-Silurian (~444 MYA) – Climate change and glaciation; major loss of marine species.
Late Devonian (~359 MYA) – Oceanic anoxia; reef ecosystems collapse.
Permian-Triassic (~252 MYA) – Largest extinction in history; 96% of marine species lost.
Triassic-Jurassic (~201 MYA) – Many marine reptiles and terrestrial species disappear; allows dinosaurs to dominate.
Cretaceous-Paleogene (~66 MYA) – Asteroid impact; dinosaurs and many marine reptiles vanish.
Holocene/Anthropocene (modern) – Rapid species loss due to human activity; considered the 6th mass extinction by many scientists.
This timeline maps major evolutionary innovations alongside catastrophic events, showing how life both adapts and is reset by mass extinctions.
If you want, I can convert this into a visually striking infographic with icons for each life form and extinction — perfect for learning or presentations.
Do you want me to do that next?
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