RT Conference Proceedings
T1 Evolution of axial regionalization in Aves during the Mesozoic and its impact on the survival of modern lineages to K/Pgmass extinction
A1 Serrano Alarcón, Francisco José
A1 Pérez-Ramos, Alejandro
A1 Chiappe, Luis M.
A1 Chapman, Susan
A1 Rashid, Dana J.
A1 Bertrand, Ornella
A1 Marcé-Nogué, Jordi
A1 Brusatte, Steve
A1 Figueirido-Castillo, Francisco Borja
K1 Aves - Evolución
K1 Vuelo de animales
K1 Aves - Columna vertebral
AB The axial column of Neornithes (modern birds) is characterized by regional fusions in caudalvertebrae (pygostyle), lumbosacrals (synsacrum), and thoracics (notarium in several taxa) thatprovide a rigid and stable axis during flight. Such a configuration integrates into a body plan highlysuited for wing-assisted locomotion (with feathered forelimbs, modified girdles, and crouched limbs)that evolved from running dinosaurs and stem birds over the last ~150 million years. Shifts in countnumbers and fusion of vertebrae have had paramount implications on the avian diversification andflight refinement. However, how the organization of precaudal vertebrae evolved across thedinosaur–bird lineage, and how and when the highly tuned axial column of neornithines wasacquired are unexplored. Here, we quantify vertebral numbers in pennaraptoran dinosaurs–including Aves—, and show how the axial configuration of birds was driven from different shiftsbetween two primary developmental mechanisms of body-axis organization: segmentation andhomeotic regionalization. We demonstrate that the configuration highly tuned for flight of modernbirds was not fully acquired until the appearance of Neornithes. The acquisition of a trunk-sacrumconfiguration more efficient to deal with stresses derived from the flapping flight could be a keyfactor in the survivorship of neornithines and the extinction of non-neornithine birds during theend-Cretaceous mass extinction event.
YR 2023
FD 2023
LK https://hdl.handle.net/10630/27495
UL https://hdl.handle.net/10630/27495
LA eng
NO Archivo que contiene el resumen y la presentación del estudio presentado en este congreso.
NO Ministerio de Ciencia, Innovación y Universidades (proyectos CGL2015-68300-P y PID2019-111185GB-I00)Junta de Andalucía (proyectos P18-FR3193 y PAIDI-DOC-00095)Natural History Museum of Los ángeles County (project ‘Aerodynamics of early birds’)Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech.
DS RIUMA. Repositorio Institucional de la Universidad de Málaga
RD 19 ene 2026