Deep TimeLife & Evolution

First mammals

225 million years agoTurning point

Small, warm-blooded, furry animals appear alongside the early dinosaurs. They nurse their young with milk.

Longest chain: The Big Bang → First stars ignite → Supernovae seed heavy elements → The Sun forms → Earth forms → First oceans → First life → Photosynthesis evolves → Great Oxidation Event → Complex cells (eukaryotes) → Multicellular life → First animals → Cambrian Explosion → First vertebrates → Jawed fish → Fish walk onto land → The amniotic egg → The Great Dying → First mammals

Community notes

Loading notes…

Learn more ranked by votes

Documentbritannica.com

Triassic Period: terrestrial reptiles and the first mammals (Britannica) ↗