Evolutionary Integration and Modularity in the Archosaur Cranium.

摘要: Complex structures, like the vertebrate skull, are composed of numerous elements or traits that must develop and evolve in a coordinated manner to achieve multiple functions. The strength association among phenotypic (i.e., integration), their organization into highly-correlated, semi-independent subunits termed modules, is result pleiotropic genetic correlations generate traits. As such, patterns integration modularity thought be key factors constraining facilitating evolution disparity by influencing variation upon which selection can act. It often hypothesized reshape integration, parceling single structures modules merging ancestrally strongly correlated unit. However, evolutionary shifts trait seldom assessed unified quantitative framework. Here, we quantify regions archosaur skull investigate whether cranial conserved variable across this diverse group. Using high-dimensional geometric morphometric data from 3D surface scans computed tomography modern birds (n = 352), fossil non-avian dinosaurs (n = 27), mesoeucrocodylians (n = 38), demonstrate some aspects these taxonomic groups, despite major differences form, function, development. All three groups highly modular consistently exhibit high within occipital region. there also substantial divergences correlation patterns. Birds uniquely between pterygoid quadrate, components kinesis apparatus, whereas dinosaur quadrate more closely associated with jugal quadratojugal. Mesoeucrocodylians slightly integrated facial skeleton overall than other grades. Overall, shown stable archosaurs, surprising given diversity exhibited clade. At same time, innovations such as reorganize structure function complex modifications modularity.