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Describe the evolution of microbes.
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Describe the evolution of microbes When the earth formed some 4.6 billion years ago, it was a lifeless, inhospitable place. A billion years later it was teeming with organisms resembling blue-green algae. How did they get there? How did life begin? Important dates in the history of life - * 4.6 billion years ago - origin of the earth * 3.5 - 4.0 billion years ago - origin of life on earth * 3.5 - 2.0 billion years ago - prokaryotes dominate * 2.7 billion years ago - oxygen accumulates in atmosphere * 2.0 billion years ago - eukaryotic life begins * 1.2 billion years ago - multicellular eukaryotes evolve Earth was formed when a very large, hot star exploded thus creating a new star (the sun) and other components of the galaxy (Madigan, Martinko & Parker 2003). Millions of years passed before the first life forms evolved on the planet. During this period, conditions on earth were very...
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