Table 2.

Loadings of three related-males fighting variables on principal components for the 45 all-unrelated combinations trios of males in our ‘synthetic’ dataset. (In PC1, all the loadings are positively correlated and are of similar magnitude, an inevitable result of the ranking of males by their lineage's aggressiveness in the creation of the dataset. Variation in PC2 is primarily defined by the range of aggressiveness phenotypes in the trio—large positive values when they are very different, and negative values when they are closer in magnitude. Variation in PC3 is primarily defined by the similarity in the level of aggressiveness of the intermediate and low aggressive lineages. The large positive PC values occur when their phenotypes are closer in magnitude.)

variable	PC1	PC2	PC3
most aggressive family	0.555	0.797	0.239
intermediate aggressive family	0.599	−0.184	−0.780
least aggressive family	0.577	−0.576	0.579
eigenvalue	2.174	0.489	0.337
% of variance explained	0.725	0.163	0.112