The Cambrian (/ ˈ k æ m b r i. ə n, ˈ k eɪ m-/ KAM-bree-ən, KAYM-) is the first geological period of the Paleozoic Era, and the Phanerozoic Eon. [5] The Cambrian lasted 51.95 million years from the end of the preceding Ediacaran period 538.8 Ma (million years ago) to the beginning of the Ordovician Period 486.85 Ma. [1]

4 天之前 · Cambrian Period, earliest time division of the Paleozoic Era and Phanerozoic Eon, lasting from 538.8 million to 485.4 million years ago. The Cambrian System, named by English geologist Adam Sedgwick for slaty rocks in southern Wales and southwestern England, contains the earliest record of abundant and varied life-forms.

4 天之前 · Cambrian Period - Fossils, Rocks, Animals: Cambrian rocks have a special biological significance, because they are the earliest to contain diverse fossils of animals. These rocks also include the first appearances of most animal phyla that have fossil records.

Learn more about a time period marked by an intense burst of evolution. The Cambrian period, part of the Paleozoic era, produced the most intense burst of evolution ever known. The Cambrian...

2012年10月28日 · The Cambrian* Period begins the Phanerozoic Eon, the last 542 million years during which fossils with hard parts have existed. It is the first division of the Paleozoic Era (542Ma -251Ma). Marine animals with mineralized skeletons make their first appearance in the shallow seas of the Cambrian, though only "small shelly fossils" (tiny shells ...

The Cambrian Period marks an important point in the history of life on Earth; it is the time when most of the major groups of animals first appear in the fossil record. This event is sometimes called the "Cambrian Explosion," because of the relatively short time over which this diversity of …

2016年5月27日 · The Cambrian Explosion was a dramatic burst of evolutionary changes in life on Earth. During the Cambrian Period, which began about 540 million years, trilobites were the dominant species.