Macroevolution - earth's continents form one large land...

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Macroevolution Milestones in Evolution The first fossil evidence of life is found in the Archaen era, around 3500 mya. During this era, prokaryote life forms diversified, the first photosynthesis appeared, producing oxygen and radically changing the atmosphere of the earth, thereby allowing for the development of aerobic respiration. The first eukaryotes do not appear until well into the Proterzoic era, approximately 1900 mya. Around 640 mya the first multicellular organisms appear. The Paleozoic era shows many major changes. After the Ordovician extinction, plants and insects begin colonizing the land. Vertebrates such as the bony fish diversify, and amphibians begin coming out of the water in the Devonian period. In the Permian period, about 290 mya, the
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Unformatted text preview: earth's continents form one large land mass called Pangaea. At this time, reptiles begin to dominate over amphibians on land. The Mesozoic era, commonly known as the "Age of the Dinosaurs", sees two major changes. The first is the diversification and domination of reptiles on land. The second is the separation of Pangaea into what will eventually become the modern continents. The Cenozoic era, which followed the mass extinction of the late Cretaceous period, takes geological history up to modern times. In this era, beginning only 65 mya, mammals and flowering plants diversify and dominate over the previously prevalent reptiles and gymnosperms. Only in the Quaternary period, the most recent period, do we see the evolution of humans....
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This note was uploaded on 01/27/2012 for the course BIOLOGY BSC1005 taught by Professor Rodriguez during the Winter '09 term at Broward College.

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