Dean - so in this case how would I use the LS means for each group (here I have only one factor and no slope) as the coordinates for the target specimen and the mean shape for all species as the reference?
Sorry I should have been more clear - the CVA was done using individual shapes, so n=161, and the bgPCA was on species means (the basic unit of my study), so n=92. I did the CVA on the individuals so as not to have more "groups" than variables and avoid false separation. I've seen your bat paper and indeed thought of doing something similar. I just liked the CVA because it showed very well the environmental gradient along which the different cranial shapes fall. On Tuesday, November 29, 2016 at 10:04:02 AM UTC+11, Christy Hipsley wrote: > > Dear Morphmet-ers, > > I'm seeking advice on methods for visualizing shape features that > distinguish multiple groups using GM. I know CVA has fallen out of favor > for a number of reasons discussed here - e.g., more variables than groups, > nonisotropic variation: > > Mitteroecker, P., and Bookstein, F. 2011. Linear discrimination, > ordination, and the visualization of selection gradients in modern > morphometrics. Evol. Biol. 38:100–114. > Klingenberg, C. P., and Monteiro, L. R. 2005. Distances and directions in > multidimensional shape spaces: Implications for morphometric applications. > Syst. Biol. 54:678–688. > > Although given these limitations, is it really expected to give completely > false results regarding the visualization of shape changes? In my study > sytem, I show that ecological groups have statistically different cranial > shapes, using both Procrustes ANOVA and PGLS. Now I simply want to > visualize what the main features are that distinguish them, preferably > using warps or wireframes, so that those changes must be directly > relateable to the original landmark coordinates. I did that using > individual specimens instead of species means, so I have 161 individuals vs > 144 variables (48 landmarks*3D). I also did a between-group PCA on the > species means which shows the same pattern, so is it technically "wrong" to > show both? > > Thanks for any feedback on this issue, and I would appreciate to hear any > alternative methods that people might use. I use MorphoJ and Geomorph for > analyses. > > Best, > Christy > -- MORPHMET may be accessed via its webpage at http://www.morphometrics.org --- You received this message because you are subscribed to the Google Groups "MORPHMET" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected].
