Publications by authors named "Theresa M Grieco"

Many reptiles are able to continuously replace their teeth through life, an ability attributed to the existence of epithelial stem cells. Tooth replacement occurs in a spatially and temporally regulated manner, suggesting the involvement of diffusible factors, potentially over long distances. Here, we locally disrupted tooth replacement in the leopard gecko () and followed the recovery of the dentition.

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We performed a test of how function impacts a genetically programmed process that continues into postnatal life. Using the dentition of the polyphyodont gecko as our model, tooth shedding was recorded longitudinally across the jaw. We compared two time periods: one in which teeth were patterned symmetrically in ovo and a later period when teeth were initiated post-hatching.

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Posso-Terranova and Andrés (2017) used harlequin poison frogs to investigate the genetic basis of pigmentation evolution and variation. Using a candidate gene approach, they clearly delimited the origins and distribution of MC1R haplotypes and associated them with key pigmentation phenotypes on multiple levels. They demonstrated that MC1R-related cellular phenotypes and associated protein truncations evolved at least twice to produce dark dorsal skin colors in different clades.

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While the identification of conserved processes across multiple taxa leads to an understanding of fundamental developmental mechanisms, the ways in which different animals fail to conform to common developmental processes can elucidate how evolution modifies development to result in the vast array of morphologies seen today-the developmental mechanisms that lead to anatomical variation. Odontogenesis-how teeth are initiated and formed-is well suited to the examination of both developmental conservation and phenotypic diversity. We suggest here that the study of early tooth development, the period of odontogenic band development, reveals departures from conserved mechanisms that question the role of players in the developmental process.

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The study of modularity can provide a foundation for integrating development into studies of phenotypic evolution. The dentition is an ideal phenotype for this as it is developmentally relatively simple, adaptively highly significant, and evolutionarily tractable through the fossil record. Here, we use phenotypic variation in the dentition to test a hypothesis about genetic modularity.

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