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A Brief History of the Earth. Timescale. 7/8 of the entire period life has existed on earth is known as the Precambrian era. During this era, life was largely single celled, and prokaryotic. Other Eras. Following the Precambrian era came the Paleozoic, Mesozoic , & Cenozoic eras.
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Timescale • 7/8 of the entire period life has existed on earth is known as the Precambrian era. • During this era, life was largely single celled, and prokaryotic.
Other Eras Following the Precambrian era came the Paleozoic,Mesozoic, & Cenozoic eras
Cambrian Explosion • At the beginning of the Paleozoic era, came the development of multicellularity. With this came an explosion of diverse life forms, only a few lines of these organisms would survive…
Cambrian species Animaloracis Trilobite
Cambrian Organisms contd. Opabinia Sidneyia
Our Distant Ancestor • Pikaia, was the first animal known to posess a notochord, and is probably the ancestor to all vertebrates. Pikaia
Ordovichian The Giant Orthocone
A Canadian Timeline • The following scenes represent the same location of northern Canada, separated only in time.
The Survivors Some early mammals survived the cataclysm. These would be the ancestors to all living mammals. Mammals weren't the only survivors, there was of course….