Figure 7.

Seasonal distributions of Per–Cry_mRNA phases for the entrained oscillators. As was seen with cortisol, the mean phase of the cell population was most advanced in the summer and delayed in the winter (right shift of distribution). Synchrony was relatively low for all seasons, and a small but distinct phase-delayed subpopulation of cells is observed for winter, autumn, and spring. ρ is the synchronization index; ${\varphi }_{\text{avg}}$ and ${\varphi }_{\text{std}}$ are the phase average and standard deviation, respectively.