The answers is fossil fuels.
Independent assortment is what causes humans to be different from each other. Humans actually share remarkably similar DNA. But, to answer your question, GENOME VARIATION are differences in the sequence in DNA, that vary from person to person.
<span>When new data calls current scientific explanation into question scientists must repeat the experiments to verify results and reevaluate said scientific explanations, if necessary, based on results, then scientists can develop a new hypothesis and test that.</span>
