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Campus Moncloa
Campus of International Excellence
Cambrian
541-485 M.a.
Cambrian derives its name from rock outcrops in an area of the United Kingdom which the Romans called Cambria.
![Mapamundi Cambrian Mapamundi](http://www.campusmoncloa.es/img/actuaciones/reloj/Cámbrico2.jpg)
Pannotia has broken up into four continents: Laurentia (approximately America and Greenland), Baltica (approximately Northern Europe), Siberia and Gondwana. The latter is a supercontinent containing South America, Africa, India, Australia, Antarctica and much of Asia and Europe, including the Iberian Peninsula.
In a short period of time, in geological terms, an explosion of life occurs. The main groups of marine invertebrates appear: arthropods, molluscs, brachiopods, annelids and the first jawless vertebrates, among others. Many of them fossilise well because they have shells and have left us characteristic fossils like trilobites or archaeocyathids.
![Opabinia a marine arthropod specimen Opabinia a marine arthropod specimen](http://www.campusmoncloa.es/img/actuaciones/reloj/cambrico-opabinia-antropodo-marino.jpg)
Opabinia, a marine arthropod specimen.
![Reproduction of Cambrian fauna. Cambrian fauna.](http://www.campusmoncloa.es/img/actuaciones/reloj/cambrico-recreacion-fauna.jpg)
Reproduction of Cambrian fauna.
Hadean | ~4600-4000 M.a. |
Archean | 4000-2500 M.a. |
Proterozoic | 2500-541 M.a. |
Cambrian | 541-485 M.a. |
Ordovician | 485-443 M.a. |
Silurian | 443-419 M.a. |
Devonian | 419-359 M.a. |
Carboniferous | 359-299 M.a. |
Permian | 299-252 M.a. |
Triassic | 252-201 M.a. |
Jurassic | 201-145 M.a. |
Cretaceous | 145-66 M.a. |
Paleogene | 66-23 M.a. |
Neogene | 23-2,6 M.a. |
Quaternary | 2,6 M.a.-act. |