I am very new to phylogenetic comparative methods but I want to explore the evolutionary patterns of a number of quantitative traits I have across a small sample (5) of closely related species (between .45mya and 4.3mya divergence). I am confident in the structure of the tree, but I only have phenotypic data for a small sample of the tree. I want to measure how correlated the evolution of the traits are across this small phylogeny and test the traits to neutral evolutionary models.
Should I even attempt this? I know that there will be limits for what I can infer about evolution of these traits, but I’m not sure where to start in terms of identifying the specific weakness. I know it will depend closely on my trait measurements, some traits display notable divergence and others do not change much across the phylogeny.
Are there any approaches that would be useful for describing the evolutionary patterns for this small sample? What references would be useful for convincing me to hold off until I have a larger phylogenetic sample? Thanks in advance for any advice!