Analysis of molecular variance of White-headed Woodpeckers. Results are shown first for an analysis in which populations were not divided into groups and then for an analysis in which populations were divided into northern and southern subspecies. p-values are the probability of getting a more extreme Φ-statistic by chance. The Φ-statistic indicates the proportion of nucleotide variation divided among populations and ranges from 0 to 1.0, with completely subdivided populations having a Φ-statistic of 1.0