Data from: The evolution of skull and body shape in Triturus newts reconstructed from 3D morphometric data and phylogeny

To explore the relationship between morphological change and species diversification we reconstructed the evolutionary changes in skull size, skull shape and body elongation in a monophyletic group of eight species that make up the salamander genus Triturus. Their well-studied phylogenetic relationships and the marked difference in ecological preferences among five species groups makes this genus an excellent model system for the study of morphological evolution. Our study involved 3D imagery of the skull and the number of trunk vertebrae, in material that represents the morphological, spatial and molecular diversity of the genus. Morphological change largely followed the pattern of descent. The reconstruction of ancestral skull shape indicated that morphological change was mostly confined to two episodes, corresponding to the ancestral lineage that all crested newts have in common and the T. dobrogicus lineage. When corrected for common descent, the evolution of skull shape was correlated to change in skull size. Also, skull size and shape and body shape - as inferred from the number of trunk vertebrae - were correlated, indicating a marked impact of species’ ecological preferences on morphological evolution, accompanied by a series of niche shifts, with the most pronounced one in the T. dobrogicus lineage. The presence of phylogenetic signal and correlated evolutionary changes in skull and body shape suggested the complex interplay of niche shifts, natural selection and constrains by a common developmental system.