fossils

Physics & Space

Earth History & Geology

• Cambrian ExplosionThe Cambrian explosion is the interval early in the Cambrian when the animal fossil record suddenly becomes much richer and many major body-plan lineages become recognizable. The current international boundary for the start of the Cambrian is 538.8 ± 0.6 million years ago.
• Earliest Life: Fossils, Inference and the Road to OxygenThe oldest surviving evidence of life supplies a minimum antiquity, not a birthday. If a convincing fossil is 3.48 billion years old, life was present by then; it may have begun much earlier. Nor does finding life in one habitat prove that life originated there.