The two main points from Darwin's theory of evolution is that 1) most, if not all living organisms evolved from one or just a few common ancestors and that subsequent specialization of further generations then led to new species. Furthermore, he said that 2) the process how this was done was by natural selection where the organisms which were most adapted to their environment were successfully 'remembered in the gene pool'.
Answer:
Scientists mostly gain new knowledge through direct observation and applying the scientific method. They would start with a hypothesis and test it, then change it or confirm it. Others would test their confirmation from one point, while the third group would test what the second said. And so on and so forth.
Explanation:
At least 12 million years ago?
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