Figure 8: Results of principal components analysis
including the variance and covariance estimates for 18 craniofacial
traits for F2 hybrids from Crescent Pond (blue triangles) and Little
Lake (green squares). Colors represent species designations and
ellipses represent 95% confidence intervals per group. Arrows display
four craniofacial traits that are most strongly correlated with PC1
(pelvic girdle length and suspensorium length) and PC2 (ectopterygoid
and head depth). Variation in Crescent Pond F2 hybrids aligns with PC2,
while variation in Little Lake is spread across both axes.