# New PDF release: Biostatistics: A Foundation for Analysis in the Health

§I (Figure 17): Both have winding number W = 1. (Examples A, B, and C are elaborated as Examples 1, 2, and 3 in the next chapter). 18 1: CiRCULAR LOGIC Figure 16. Clock phase varies one-to-one with longitude. 0"--360" PHASE OIFFERENCE Example D. A starling is ready to migrate south, a direction it knows relative to the Sun. A physiologist (Hoffmann, 1960) resets the phase of its circadian dock by six hours (one-quarter cyde) and releases it.

3. When parent phases 4>A and 4>B are nearly the same, the hybrid phase 4>' is nearly the same as both. Referring to Figure 23, consider what happens to 4>' if 4>Ais increased through a full cycle while c/Ja is held fixed (at a value that we mayas weIl call 4>B = 0). If 4>' changes, it must change in such a way as to return to its first value as 4>A completes its scan of the cycle. As in earlier examples, the periodic dependence of 4>' on 4>A has an integer winding number, the number of times 4>' runs through its cycle as 4>A runs forward through its cycle.