Dental measurement and diet data for mammals

Because teeth are the most easily preserved part of the vertebrate
skeleton and are particularly morphologically variable in mammals, studies
of fossil mammals rely heavily on dental morphology. Dental morphology is
used both for systematics and phylogeny as well as for inferences about
paleoecology, diet in particular. We analyze the influence of evolutionary
history on our ability to reconstruct diet from dental morphology in the
mammalian order Carnivora, and we find that much of our understanding of
diet in carnivorans is dependent on the phylogenetic constraints on diet
in this clade. Substantial error in estimating diet from dental morphology
is present regardless of the morphological data used to make the
inference, although more extensive morphological datasets are more
accurate in predicting diet than more limited character sets.
Unfortunately, including phylogeny in making dietary inferences actually
decreases the accuracy of these predictions, showing that dietary
predictions from morphology are substantially dependent on the
evolutionary constraints on carnivore diet and tooth shape. The
“evolutionary ratchet” that drives lineages of carnivorans to evolve
greater degrees of hypercarnivory through time actually plays a role in
allowing dietary inference from tooth shape, but consequently requires
caution in interpreting dietary inference from the teeth fossil
carnivores. These difficulties are another reminder of the differences in
evolutionary tempo and mode between morphology and ecology.