Breaking the rules: Phylogeny, not life history, explains dental eruption sequence in primates.

Schultz's Rule, as it is currently written and applied, is not supported by this extended data set. Our results demonstrate that dental eruption sequence is a far better predictor of phylogeny and will likely prove useful in phylogenetic hypotheses about relationships between extinct and extant mammalian taxa. The evolution of dental eruption sequence is likely driven by factors that significantly influence body size and mandibular symphyseal fusion.