M Mercury 2010 Guest Mar 19, 2009 #2 dinosaurs became the dominate life on planet earth about 200 million years ago. they became extinct 70 million years ago. (I still see some dinosaurs in retirement homes but they won't last much longer)
dinosaurs became the dominate life on planet earth about 200 million years ago. they became extinct 70 million years ago. (I still see some dinosaurs in retirement homes but they won't last much longer)
L lindajune Guest Mar 19, 2009 #4 The Earth's atmosphere was being changed by photosynthesizing plants and was about 35% oxygen at that time. Pangaea was breaking apart to form the continents.
The Earth's atmosphere was being changed by photosynthesizing plants and was about 35% oxygen at that time. Pangaea was breaking apart to form the continents.
