Cambrian Explosion

(570-530) million years ago

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This is the earliest of the Palaeozonic Era.During this period a explosion of variation occurred, the ancestors of many living animals today began. Some lineages rose and disappeared.Natural Selection selects for larger, and fit animals which gave way to hard exoskeleton (chordata) organisms such as trilobites, mollusks,echinoderms and many other odd animals whose genealogies have disappeared over the years; more than 900 species have been recorded. Many changes of period took over 5-30 million years to occur, this was what made this time period so special because so many changes occurred in a short amount of time.

Mollusks
Mollusks
echinoderms
echinoderms
Trilobites
Trilobites


The enviroment during the Cambrian period is different from the present day. Fossils found from the Cambrian period indicates that there were three major faunal regions.The Cambrian enviroment consisted of lagoons, sandstone and mudstone. It was shallow water with carbonate platforms. The region Laurentina consisted of lagoons, the region Baltica consisted of sandstone and the biggest region Gondawana consisted of mudstone.


´╗┐Earth during the late Cambrian Period


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