Craniofacial development is framed as an integrated, multi-factor morphogenesis system in this period. Palate closure is seen as a dynamically coordinated mechanical sequence where palatal shelf elevation, tongue interactions, and cranial base straightening drive fusion, supported by direct shelf movement studies and teratogen manipulations. Epithelial seam biology centers on midline epithelial structure and disruption as key to seam breakdown, shaped by surface topography and contact-mediated processes. Growth and morphogenesis across species reveal distinct trajectories and timing, with genetic, strain, and sex variation modulating risk; methodological integration across radiographic tracing, scanning electron microscopy plus electron microscopy imaging, in vitro organ culture, and histology illuminates palate formation across models. Historical Significance: The era crystallizes the neural crest as a central driver of craniofacial development through fate-mapping efforts, demonstrates distinct embryonic origins of craniofacial muscles and connective tissues, and reframes craniofacial biology with a holistic view of skull form as the product of genotype, phenotype, and environmental context. Foundational work on secondary palate formation consolidates shelf elevation and fusion within a matrix and muscular activity framework, while studies of meninges formation clarify tissue origins and their relationship to skull and brain development. Together, these findings established an integrated, lineage-informed paradigm that guided later evo-devo and developmental biology.