We all know that the plants we see now were on the planet far before we were, and as plants release oxygen, it's fair to say this has had a huge impact on animals. Humans have a huge impact
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But in fact, the original plants are growing in the water, and you can not accurately say that they are plants, but unicellular plants, with the changes in the external environment, from unicellular evolution to multicellular, in fact, we can actually see now is algae. From aquatic plants began to slowly go to the land to develop, moss this class is a good explanation, know ferns can only be said to be from aquatic plants into the terrestrial plants
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And in this process, the plants continue to evolve, there are some plants continue to be eliminated, and slowly disappeared from the earth, but wherever the last to stay! But all the last to stay is to go through a painful and long process, in order to adapt to the growth of land, they began to produce roots, crushed rocks into suitable soil for growth, in order to absorb more carbon dioxide, began to produce leaves, so the premise of the change of fate is that they want to change for the better