Fig. 3

Relative abundance, not composition, of haplotypes of I. scapularis varies among regions. A Although closely related ticks could be found across New York, ticks within each clade tended to cluster geographically, suggesting isolation by distance at fine spatial scales. Dated maximum clade credibility (MCC) phylogeny of the best-fitting model inferred with BEAST (strict molecular clock model; Bayesian extended skyline population size) of I. scapularis in NY. Tips are collapsed into major clades in order to depict coarse scale patterns. Each clade is labeled with the number of ticks it contains. B Bar chart depicts the proportion of ticks from each clade found in each region. At least one tick from each clade was present within each region except that the Clade 1 is not present in the North region. Importantly, the proportion of ticks from each clade varied across New York regions. Ticks collected in the Hudson River Valley were distributed relatively evenly among the phylogenetic clades, whereas ticks from only two clades dominated in the North region. C Although closely related ticks could be found across New York, ticks within each clade tended to cluster geographically, suggesting isolation by distance at fine spatial scales. Clade 1 of the dated phylogeny of I. scapularis in New York with tips are colored by sampling region. In this example, ticks from four of the five regions were represented with unmistakable geographic clustering. That is, ticks from the East Central region were most closely related to each other while ticks from the Hudson River Valley were most closely related to each other