Evolutionary implications of dental anomalies in bats

The gain or loss of anatomical features is an important mechanism of
morphological evolution and ecological adaptation. Dental anomalies –the
loss or gain of teeth– are widespread and a potential source of
craniodental specialization among mammals, yet their macroevolutionary
patterns have been rarely explored. We present the first phylogenetic
comparative study of dental anomalies across the second largest mammal
Order, Chiroptera (bats). We conducted an extensive literature review and
surveyed a large sample of museum specimens to analyze the types and
prevalence of dental anomalies across bats, and performed phylogenetic
comparative analyses to investigate the role of phylogenetic history and
dietary specialization on incidence of dental anomalies. We found dental
anomalies have a significant phylogenetic signal, suggesting they are not
simply the result of idiosyncratic mutations or random developmental
disorders, but may have ancestral genetic origins or result from shared
developmental pathways among closely related species. The incidence of
dental anomalies was not associated with diet categories, suggesting no
effect of craniodental specialization on dental anomalies across bats. Our
results give insight into the macroevolutionary patterns of dental
anomalies in bats, and provide a foundation for investigating new
hypotheses underlying the evolution of dental variation and diversity in
mammals.