Cambrian Period

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Cambrian period 543-490 million years Introduction The Cambrian Period marks the beginning of the Paleozoic Era. This period gets its name from a place in Wales where the first examples of this type of ancient life was found. The period lasted for nearly 53 million years, from about 543 million years ago until 490 million years ago. 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 forms appears. It was once thought that the Cambrian rocks contained the…show more content…
* Burgess Shale - One of the greatest fossil finds ever made is the Burgess fauna of British Columbia. Thousands of soft-bodied animal fossils paint us a picture of early marine life. * House Range, Utah - A varied array of Cambrian critters has been found in the Wheeler Shale and the Marjum Formation, both of which are exposed in the House Range. * Marble Mountains - In the hottest part of the Mojave Desert of California is the rich Latham Shale where Olenellid trilobites are numerous. * White-Inyo Mountains - You can visit ancient reefs in the mountains of eastern California. Cambrian life Explosion of Invertebrate Life During the Cambrian Period there was an explosion of life forms. Most of these were in the water. Many animals with no backbones lived in the shallow seas. These animals were invertebrates. Almost every metazoan phylum with hard parts, and many that lack hard parts, made its first appearance in the Cambrian. The only modern phylum with an adequate fossil record to appear after the Cambrian was the phylum Bryozoa, which is not known before the early Ordovician. A few mineralized animal fossils, including sponge spicules and probable worm tubes, are known from the Vendian period immediately preceding the
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