Table 1 The first principal component explains at least 75% of the variation in wing shape during gliding in pigeons.

Together, the first two principal components (PCs) represent at least 97% of the variation. This implies that a two–degree of freedom mechanism replicates almost all measured wing motion and that a single–degree of freedom mechanism represents the majority of the motion.

Pigeon 174.5%22.5%1.64%0.48%0.38%
Pigeon 292.2%4.94%1.62%0.55%0.34%
Pigeon 386.4%9.85%2.37%0.63%0.23%