Delineating population structure from the marker genotypes of a sample of individuals is now routinely conducted in the fields of molecular ecology, evolution and conservation biology. Various Bayesian and likelihood methods as well as more general statistical methods (e.g. PCA) have been proposed to detect population structure, to assign sampled individuals to discrete clusters (subpopulations), and to estimate the admixture proportions of each sampled individual. Regardless of the methods, the power of a structure analysis depends on the strength of population structure (measured by F