<span>Natural selection leads to speciation because as populations in a species change due to mutations, the less fit organisms die out, while the fit organisms survive and pass on their genes. As this process continues, the evolved population will eventually accumulate enough genetic changes, such that the evolved population can no longer produce fertile offspring with the original population, hence it is said that speciation has occurred. </span>
Generally, saying no to drugs is the best outcome. But also not being Under the Influence is best too.
