Supplementary material from "From teeth to pad: tooth loss and development of keratinous structures in sirenians" ...

• Main Authors: Hautier, L., Gomes Rodrigues, H., Ferreira-Cardoso, S., Emerling, C. A., Porcher, M.-L., Asher, R., Portela Miguez, R., Delsuc, F.
• Format: Article in Journal/Newspaper
• Language: unknown
• Published: The Royal Society 2023
• Subjects: Evolutionary biology not elsewhere classified; Plant cell and molecular biology; Animal cell and molecular biology; Palaeontology incl. palynology; Steller's sea cow
• Online Access: https://dx.doi.org/10.6084/m9.figshare.c.6927574.v1; https://rs.figshare.com/collections/Supplementary_material_from_From_teeth_to_pad_tooth_loss_and_development_of_keratinous_structures_in_sirenians_/6927574/1

Sirenians are a well-known example of morphological adaptation to a shallow-water grazing diet characterized by a modified feeding apparatus and orofacial morphology. Such adaptations were accompanied by an anterior tooth reduction associated with the development of keratinized pads, the evolution of which remains elusive. Among sirenians, the recently extinct Steller's sea cow represents a special case for being completely toothless. Here, we used μ-CT scans of sirenian crania to understand how motor-sensor systems associated with tooth innervation responded to innovations such as keratinized pads and continuous dental replacement. In addition, we surveyed nine genes associated with dental reduction for signatures of loss of function. Our results reveal how patterns of innervation changed with modifications of the dental formula, especially continuous replacement in manatees. Both our morphological and genomic data show that dental development was not completely lost in the edentulous Steller's sea cows. By ...