SSI generalist-only populations exhibit unique P matrix properties
that are not observed in Caribbean or SSI radiating populations.
The visualization of the PCA suggests that the P matrix of SSI
generalist-only populations is distinct from both the Caribbean and SSI
radiating groups (Figure 4). In direct comparisons, we found that the
SSI radiating, and Caribbean groups had the highest level of PCA
similarity indicating that the P matrices of these two populations are
extremely similar (Figure 5; Appendix Table C1). Direct comparisons of
each of these groups with SSI generalist-only populations also indicates
that their P matrices are significantly different. Specifically, the P
matrix of the SSI generalist-only group has significantly higher levels
of integration, constraints and mean squared correlation between traits,
with simultaneously lower estimates of flexibility than the P matrices
of SSI radiating and Caribbean populations (Figure 6; Appendix Table
C2). In fact, there are only two P matrix features for which the SSI
generalist-only group is similar to other pupfish populations:
respondability and autonomy. For respondability, both SSI radiating and
SSI generalist-only populations exhibited similar values
(respondability= ~0.09), while the Caribbean population
value was approximately half of this estimate (respondability= 0.048).
On the other hand, autonomy estimates for the Caribbean and SSI
generalist-only group were extremely similar
(autonomy=~0.07), while the P matrix of SSI radiating
populations had significantly lower values (autonomy=0.034) (Figure 6;
Appendix Table C2).