In this exercise, you will compare the amino acid sequence from the aphid to the amino acid sequences of the other species to identify how similar they are. As a first step, you will compare the aphid sequence (Acyrthosiphon) to a bacterial sequence (Pantoea). The sequences below show the first 60 amino acids of one polypeptide, using the one-letter abbreviations for the amino acids. An underscore (_) indicates a gap inserted in a sequence to optimize its alignment with the corresponding sequence in Arabidopsis.