Following Glenn comments im editing my question and posting an example:
I want to know if my procedure here is valid.
We tested the relationship between ecomorph and escape behavior across ten species using Phylogenetic Generalized Least Squares. To assess if environmental context (sand versus leaf litter) affected escape strategy within each species, we used a phylogenetic t-test (package phytools) that compares the response among contexts and across species. Both analyses assume escape strategy is a continous variable in which burrowing is coded as 3,hiding as 2 and running as 1. Despite this maneuver allows accounting for phylogenetic non independence, is not the best description for the response variable, which conforms with a typical multinomial ordered variable. Thus we also fitted a categorical ordered model with both morphotype and environment simultaneously predicting escape strategy using the “polr” function. The high t-values and z-tests agree with phylogenetic analyses suggesting significant effects of both, morphotype and environment (see tables and figure)
Results of multinomial ordered model assessing effects of morphology and environmental context on the odds of using different escape strategies
Estimate Std. Error z value Pr(>|z|) morph snake-like 3.38739 0.24791 13.6637 < 2.2e-16 treatment sand -1.42388 0.20554 -6.9275 4.28E-12
Results of PGLS test of the effects of morphotype on escape response.
PGLS: n=10, lambda= -0.1878671, coeff= 1.103697, t-value= 10.01984, p <0.001).
Results of Phylogenetic t-test of the effect otf the context over escape strategy Pt-test: n=10, lambda=1, t= 2.430056, p=0.04541684)