Cambrianera

Cambrianera refers to the Cambrian period, the first period of the Paleozoic Era in the geologic timescale. It lasted roughly 541 to 485.4 million years ago. The term Cambrianera is sometimes used in non-technical contexts or in languages where Cambrian Period is rendered as Cambrianera; in English, Cambrian Period is the standard name. The term Cambrian comes from Cambria, the Latin name for Wales, where rocks of this age were first studied.

The Cambrian era is best known for the Cambrian explosion, a rapid diversification of multicellular life in the oceans that results in the appearance of most major animal phyla in the fossil record. Life was predominantly marine, with early skeletonized arthropods, mollusks, brachiopods, echinoderms, and early chordates among the notable groups. The development of hard parts such as shells and exoskeletons greatly enhanced fossil preservation and produced an abundant, recognizable fossil record.

Fossil evidence from the Cambrian includes famous Lagerstätten that provide insight into early animal life, such as the Burgess Shale deposits in what is now Canada and the Chengjiang fossil beds in China. These sites preserve a wide range of soft-bodied organisms, complementing the better-known hard-shelled fossils.

Geographically, landmasses were arranged differently from today, with much of the area covered by shallow seas. Global climate was generally warm, with high sea levels that created expansive epicontinental basins.

The Cambrian is conventionally divided into lower, middle, and upper phases, sometimes referred to as series or stages. It ends with the base of the Ordovician, marking the transition to further diversification and subsequent extinctions.