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.

"[An] extraordinary book. . . . Mr. Gould is an exceptional combination of scientist and science writer. . . . He is thus exceptionally well placed to tell these stories, and he tells them with fervor and intelligence."—James Gleick, New York Times Book Review High in the Canadian Rockies is a small limestone quarry formed 530 million years ago called the Burgess Shale. It hold the remains of an ancient sea where dozens of strange creatures lived—a forgotten corner of evolution preserved in awesome detail. In this book Stephen Jay Gould explores what the Burgess Shale tells us about evolution and the nature of history.

Unlike some other reproductions of classic texts (1) We have not used OCR(Optical Character Recognition), as this leads to bad quality books with introduced typos. (2) In books where there are images such as portraits, maps, sketches etc We have endeavoured to keep the quality of these images, so they represent accurately the original artefact. Although occasionally there may be certain imperfections with these old texts, we feel they deserve to be made available for future generations to enjoy.