Around day 2 PI, the mean phases (hour GMT ± SD) are 19.58 ± 0.28 for WT matched infections, 14.95 ± 0.38 for WT mismatched, 16.07 ± 0.15 for Per1/2‐null TRF and 16.63 ± 0.07 for Per1/2‐null all‐day fed (Figure 4b,c; Figure 4b). Here, PER1 is linked to infection.