My research group is interested in a variety of topics related to the vertebrate craniofacial (head) development, craniofacial genetic conditions in humans and craniofacial developmental evolution. We use morphometric, molecular, cellular and genetic approaches to study the precise mechanisms of cranial skeletal cell differentiation and skull/face morphogenesis in amniotes. The species we work with range from the laboratory "model" systems, such as chicken embryos and mouse mutants, to the "non-model" species used for evolutionary developmental studies, for example, Darwin's Finches and their relatives from Caribbean Islands, as well as other birds and, more recently, reptiles, both squamates (e.g. Anolis lizards), and archosaurs, such as alligators. This combination of laboratory "model" species with "non-model" species from natural environments allows us to address important conceptual questions, such as the roles of particular developmental genetic mechanisms (e.g. modularity) in evolution of adaptive variation and significant morphological transitions at both small and large evolutionary scales.
Generally, our studies on evolutionary developmental biology (Evo-Devo) have a tripartite structure of the overall approach: 1) The first step is quantification of morphological variation using methods ranging from simply scoring the absence or presence of particular structures to 3D imaging and modeling; 2) The second component is identification of candidate genetic and developmental mechanisms using methods ranging from observations of the trait as it emerges in real time to quantitative trait locus (QTL) mapping to microarray and RNAseq screens;3) The third part is functional assays of candidate genes/pathways to reveal the more causative relationships by methods ranging from physical manipulations to tissue and embryo transgenesis with molecular vectors.
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et al., 2004, Bmp4 and morphological variation of beaks in Darwin's finches, Science, Vol:305, ISSN:0036-8075, Pages:1462-1465
et al., 2006, The calmodulin pathway and evolution of elongated beak morphology in Darwin's finches, Nature, Vol:442, ISSN:0028-0836, Pages:563-567
et al., 2007, Regulation of skeletogenic differentiation in cranial dermal bone, Development, Vol:134, ISSN:0950-1991, Pages:3133-3144
et al., 2010, Scaling and shear transformations capture beak shape variation in Darwin's finches, Proceedings of the National Academy of Sciences of the United States of America, Vol:107, ISSN:0027-8424, Pages:3356-3360
et al., 2011, Two developmental modules establish 3D beak-shape variation in Darwin's finches, Proceedings of the National Academy of Sciences of the United States of America, Vol:108, ISSN:0027-8424, Pages:4057-4062
et al., 2012, Paths Less Traveled: Evo-Devo Approaches to Investigating Animal Morphological Evolution, Annual Review of Cell and Developmental Biology, Vol:28, ISSN:1081-0706, Pages:743-763
et al., 2012, Birds have paedomorphic dinosaur skulls, Nature, Vol:487, ISSN:0028-0836, Pages:223-226
et al., 2012, Closely related bird species demonstrate flexibility between beak morphology and underlying developmental programs, Proceedings of the National Academy of Sciences of the United States of America, Vol:109, ISSN:0027-8424, Pages:16222-16227
et al., 2013, CONVERGENT EVOLUTION OF SEXUAL DIMORPHISM IN SKULL SHAPE USING DISTINCT DEVELOPMENTAL STRATEGIES, Evolution, Vol:67, ISSN:0014-3820, Pages:2180-2193
et al., 2013, von Baer's law for the ages: lost and found principles of developmental evolution, Trends in Genetics, Vol:29, ISSN:0168-9525, Pages:712-722
et al., 2015, A molecular mechanism for the origin of a key evolutionary innovation, the bird beak and palate, revealed by an integrative approach to major transitions in vertebrate history, Evolution, Vol:69, ISSN:0014-3820, Pages:1665-1677