Chapter 2. Biological Sequences

Sequence similarity is a powerful tool for discovering biological function. Just as the ancient Greeks used comparative anatomy to understand the human body and linguists used the Rosetta stone to decipher Egyptian hieroglyphs, today we can use comparative sequence analysis to understand genomes, RNAs, and proteins. But why are biological sequences similar to one another in the first place? The answer to this question isn't simple and requires an understanding of molecular and evolutionary biology.