The plots of the Principal Components subreport show the spread of individuals on the axis formed by the principal components that are estimated from the output relationship matrix. These plots help you visualize whether individuals can be put into groups, in other words, if the individuals belong to some subpopulation, which indicates the presence of population structure among individuals. The principal component scores of each individual can be extracted for this report and used in subsequent analysis, such as Genome Wide Association Analysis (GWAS).