Data from: Are developmental shifts the main driver of phenotypic evolution in Diplodus spp. (Perciformes: Sparidae)?

Background: Sparid fishes of the genus Diplodus show a complex life
history. Juveniles have adaptations well suited to life in the water
column. When fishes recruit into the adult population individuals develop
a radically differentiated shape that reflect their adaptation to the new
benthic environment typical of the adult. By using a geometric
morphometric approach, we investigated the pattern of shape variation
across ontogenetic stages that span from early settlement to the adult
stage in four species of the genus Diplodus. Landmarks were collected on
the whole body of fishes to quantify the phenotypic variation along two
well defined life stages, i.e. juvenile and adult. A comparative analysis
of ontogenetic trajectories was performed to assess the presence of
divergence in the developmental pattern. Subsequently, we investigated the
patterns of integration and modularity as proxy of the alteration of the
developmental processes. This allowed to have an insight in morphological
developmental patterns across ecologically and ontogenetically
differentiated life stages and to investigate the process leading to the
adult shape. Results: Our results suggest that the origin of morphological
novelties in Diplodus spp. arise from shifts of the ontogenetic
trajectories during the development. During the settlement phase,
juvenile’s morphological shapes converge towards close regions of the
morphospace. When the four species approach the transition between
settlement and recruitment we observe the lowest level of inter- and
intra-specific disparity. After this transition we detect an abrupt shift
of ontogenetic trajectories, i.e. the path taken by species during
development, that led to highly divergent adult phenotypes. Discussion: We
suggest that the evolution of new ecomorphologies, better suited to
exploit different niches and reduce inter-specific competition in Diplodus
spp., are related to the shift in the ontogenetic trajectory that in turn
is associated to changes in modularity and integration pattern.