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John Foster - Life of the Past: Cambrian Ocean World : Ancient Sea Life of North America read online DOC, TXT

9780253011824


0253011825
This volume, aimed at the general reader, presents life and times of the amazing animals that inhabited Earth more than 500 million years ago. The Cambrian Period was a critical time in Earth's history during this immense span of time nearly every modern group of animals appeared. Although life had been around for more than 2 million millennia, Cambrian rocks preserve the record of the first appearance of complex animals with eyes, protective skeletons, antennae, and complex ecologies. Grazing, predation, and multi-tiered ecosystems with animals living in, on, or above the sea floor became common. The cascade of interaction led to an ever-increasing diversification of animal body types. By the end of the period, the ancestors of sponges, corals, jellyfish, worms, mollusks, brachiopods, arthropods, echinoderms, and vertebrates were all in place. The evidence of this Cambrian ""explosion"" is preserved in rocks all over the world, including North America, where the seemingly strange animals of the period are preserved in exquisite detail in deposits such as the Burgess Shale in British Columbia. Cambrian Ocean World tells the story of what is, for us, the most important period in our planet's long history., This volume, aimed at the general reader, presents the story of the Cambrian Period and of its amazing variety of animals. The Cambrian was a critical time in Earths history during which nearly every modern group of animals appeared. Although life had been around for more than two million millennia, Cambrian rocks preserve the record of the first appearance of complex animals with eyes, protective skeletons, antennae, and complex ecologies. Grazing, predation, and multi-tiered ecosystems with animals living in, on, or above the sea floor became common. The cascade of interaction led to an ever-increasing diversification of animal body types. By the end of the period, the ancestors of sponges, corals, jellyfish, worms, mollusks, brachiopods, arthropods, echinoderms, and vertebrates were all in place. The evidence of this Cambrian "explosion" is preserved in rocks all over the world, including North America, where the seemingly strange animals of the period are preserved in exquisite detail in deposits such as the Burgess Shale in British Columbia. They tell the story of what is, for us, the most important period in our planets long history.

Ebook Life of the Past: Cambrian Ocean World : Ancient Sea Life of North America by John Foster MOBI