Early Cambrian
From Palaeos
| Cambrian period 542-488 | |||||||||
|---|---|---|---|---|---|---|---|---|---|
| Early Cambrian 542-521 | Middle Cambrian 521-501 | Furongian 501-488 | |||||||
| Series 2 521-510 | Series 3 510-501 | ||||||||
| Fortunian 542-535 | Stage 2 535-521 | Stage 3 521-517 | Stage 4 517-510 | Stage 5 510-506 | Drumian 506-503 | Guzhangian 503-501 | Paibian 501-496 | Stage 9 496-492 | Stage 10 492-488 |
| Cambrian topics: Stratigraphy | Geography | Climate | Life | Important Fossil Sites | References | Links | |||||||||
542.0 to 513.0 million years ago
| Top: Geological Timescale |
| Up: Cambrian Period |
| [[Next: Middle Cambrian]] |
| Early Cambrian |
| Scientific History | Geography | Climate | Life | Important Fossil Sites | References | Links |
This was a time of great change across a wide spectrum, from tectonic (the breakup of the early Rodinia and Pannotia supercontinents) through geographical (marine transgressions as the ocean invaded the land creating shallow continental seas that allowed primitive life to flourish), atmospheric, (rising oxygen and falling carbon dioxide levels), biogeochemical (changing ocean chemistry, promoting biomineralization; especially the upwelling of high phosphorous levels (large phosphorite deposits), enabling organisms to develop skeletons of calcium phosphate), and ecological (the appearance of predation and algae grazers, which meant an end of the Ediacaran idyll). This combination of events would seem to have been responsible for the sudden and remarkable diversification of metazoan life at this time.
