Jaw kinesis in snakes: the evolution and development of novel structures and enormous gapes

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We aim to study the development and evolution of the unique snake jaw. This researchinvestigates the mechanisms behind the evolution of novel structures and provides anunderstanding of how cranial joints evolved and form embryonically. Aims: 1. Tocharacterise the development and precise anatomy of the highly flexible jaw joints inthe corn snake embryo 2. To compare and contrast the development of the snake jawwith that of lizards and chicks, and to identify the mechanisms that shape theseskeletal elements during embryology. 3. To correlate developmental mechanisms withadult morphology, across snake species, using 3D imaging, geometric morphometrics(programming skills in R), and evolutionary modeling to understand the origins of jawdiversity. 4. To develop new statistical models to model the tempo and mode ofevolution in the snake jaw, from early fossil snakes to modern snakes and acrossecological groups. Tucker Lab: These aims will take advantage of the corn snakecolony (Elaphe guttata) established by Prof Tucker at King's. The jaw will beinvestigated using immunohistochemistry, in situ hybridisation and analysis ofproliferation and cell death. Imaging will involve microCT and confocal microscopy.Several corn snake genes have already been cloned in the lab (Shh, Ptc, Axin2, Lef1).Snake jaws will be compared to those of other species (embryos available at King's),with respect to differences in gene expression, morphology, and cell dynamics. Felicelab: The project will quantify tempo and mode of anatomical evolution in differentsnake species using cutting-edge imaging, 3D morphometric analysis in R andevolutionary modelling. The student will develop new methods for Bayesianprobabilistic modeling to test hypotheses about how anatomical variation arose in thejaw (i.e., do the correlations among jaw bones constrain evolution?). These newtechniques will provide a useful framework for analysis of other evolutionary novelties.