Consider Figure 4.12 (A) on page 99. Why does the caption of the figure (on page 98) claim that hits above the arrow are significant, while the ones below are not. Fully explain.
The last column in the table is the E-value which is similar to a p-value when testing for significance. The hits above the arrow have a very tiny E-value: 2e-90 or less. In other words, the probability that these results occur by chance is vanishingly small. The hit below the arrow has an E-value of 0.59 which is quite large as these things go. Any hits below that row will have even greater values, so will be of even less significance.