Lagothrix and Ateles are frugivorous, while Alouatta and Brachyteles
are folivorous. The primitive diet for the clade's common ancestor is
believed to have been a frugivorous one (Rosenberger and Strier, 1989),
so that the similarity between Ateles and Lagothrix could be consid-
ered symplesiomorphic (a retained primitive state inherited from a
common ancestor). In contrast, folivory was probably developed in par-
allel in Alouatta and Brachyteles (Rosenberger and Strier, 1989). If
that is the case, why are these genera no more similar in their facial
shape? Cole et al. (2000) hypothesized that any similarities between
Alouatta and Brachyteles that are due to a common diet are probably
obscured by the unusually derived facial form in Alouatta , which is
modified as the result of a hypertrophied hyolaryngeal apparatus
(Rosenberger and Strier, 1989).
This chapter has offered new extensions of basic EDMA procedures as
well as new algorithms for addressing complex biological problems.
The examples given in the chapter demonstrate the versatile nature of
the basic EDMA approach and underscore the essential importance of
invariance in adapting the method to new areas of morphometric
description and comparison. The applications demonstrated here are
simply examples, and we are confident that future applications will be
many and diverse.