Figure 3.

Results of hierarchical STRUCTURE population clustering. The initial STRUCTURE run split the populations of Rana pipiens in North Dakota into two main clusters separated by the Missouri River; Populations 1–12 and 14 were to the southwest, whereas all remaining populations were northeast of the Missouri. The populations west of the Missouri River broke into four clusters when analyzed separately. The populations east of the Missouri River clustered into two large groups, one in the northwestern part of the state and one in the southern and eastern parts of the state. Each of these two groups further clustered into three clusters largely separated by basin