Chapter 1: A Universe of Life - Sierra College

C) 360 million years ago. D) 545 million years ago. E) 2.1 billion years ago. 162. The colonization of life onto land was closely tied to the. A) appearance of multicellular organisms B) development of photosynthesis. C) oceans being overcrowded. D) development of the ozone layer. E) the formation of the Earth’s magnetic field. 163. ................
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