<span>Looking at the two species' DNA would be a good place to start. If there are a number of similarities in their genotypes, then there would be a good chance that the two would also share some type of a common ancestor. This would be evidence that there was some type of selection that took place that necessitated two different species that shared a number of traits and features.</span>
If reproduction didn't exist, all species would eventually go extinct.
Structurally
DNA and RNA<span> are nearly identical. As mentioned earlier, however, there are three fundamental </span>differences<span> that account for the very </span>different<span> functions of the </span>two<span> molecules. </span>RNA<span> has a ribose sugar instead of a deoxyribose sugar like </span>DNA.RNA<span> nucleotides have a uracil base instead of thymine.
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p.s (google helped)
Answer: I hope it helps!!
Explanation: I can't really explain on computer through a keyboard and stuff lol, but it's worked out. Please let me know if it's wrong :-)