First record of a giant bird (Ornithuromorpha) from the uppermost Maastrichtian of the southern Pyrenees, NE Spain.
Creators: name: Eduardo Puertolas Pascual
Publisher: name: Zenodo
Year: 2023
Subjects: Ornithuromorpha)
Late Cretaceous
Computed Microtomography
Paleogene
3d models
fossils
bones

description: Objectives:The services provided by the CENIEH, in this casethe application of Computed Microtomography (micro Tac) to fossilbones, have beenused several times. The main goalhas been toscan Mesozoic vertebrates, mainly crocodiles, with the intentionof seeing cavitiesand other internalstructures that are usually hiddenor inaccessible due to the rocky matrix thatcontains the fossil. The purpose ofthe data obtainedfrom the microTACcan be summarizedas:- Internal anatomyof fossils: CTscans allow paleontologists to visualize the internal structures of fossils withouthaving to damagethem. This includesbones, teeth, softtissues, and insome cases even preserved organs.- Three-dimensional reconstruction: From the images obtainedwith the TAC scanner, accurate 3D models of the fossils canbe created. This facilitates the detailed study of morphology and allows the analysis of functional and evolutionary aspects.- Taxonomic comparisons: The CT scanis a valuabletool that allowsto observe anatomical features that maybe hidden from the naked eye, such as sutures, internal cavities, etc. Obtaining thisinformation is very useful for classifying and comparing extinct species with other knownones. This helpsto determine evolutionary relationships and to understand pastbiodiversity.- Behavioral study: By analyzing fossilsin their three-dimensionalcontext, scientists can infer aspects of the behavior and ecology ofextinct organisms. In our case, the CT imagesand 3D models generated can beused for paleoneuroanatomy studies. Paleoneuroanatomy is a branch of paleontology thatfocuses on the study of the brain structures and nervous systemof extinct organismsthrough the analysisof fossils andendocranial molds. Its goal is to reconstruct andunderstand the brain anatomy ofancient species to gain informationabout their behavior, cognitive ability and evolution. GettingThree-Dimensional Imaging: CT scans use X-rays to getdetailed pictures of the interiorof the skulland other tissues. These images aregenerated in cross-sectionsand then combinedto create accurate3D models of the endocranial cavity. CT scansidentify and mapor segment impressionsand internal characteristics of the skull, which correspond to brain structuressuch as thebrain, cerebral ventricles, olfactory bulbs, inner ear, and other partsof the nervoussystem. From thesedata, accurate measurements of theendocranial cavity can be made and compared with modern species to infer aspects related to the ize and shape of the brainof fossil organisms. This allows inferencesto be madeabout the cognitive, sensory and behavioralcapacities of fossil organisms. For example, it ispossible to estimate cognitive, visual, olfactory, auditory skills, etc. Thus, comparing fossil brains with those of modern species helps tounderstand the evolution of thenervous system and provides informationabout changes inbehaviour and cognitionover time. 
Study:
In the evolutionary history of birds, giant forms have developed in different periods and ecological contexts. In Europe, the first large birds, the Gargantuaviidae, appeared during the Late Cretaceous, and during the Paleogene more groups evolved into large forms. However, until now, no giant birds had been recorded during the terminal Maastrichtian in Europe, near the Cretaceous/Paleogene (K/Pg) boundary when non-avian dinosaurs became extinct. In this study we describe a cervical vertebra from Beranuy (Huesca, NE Spain), which represents the first fossil evidence of a giant bird from the late Maastrichtian of Europe. The microtomography of the vertebra performed at the CENIEH allowed us to reconstruct its cavities, revealing a very large and intricate system of pneumatic cavities, being one of the characteristics that allowed us to assign it to Avialae. This finding demonstrates that large birds were part of the ecological communities of Iberia at the end of the Cretaceous, being present in the last hundreds of thousands of years before the K/Pg mass extinction event. 
"This report acknowledges the financial support of the Access to Research Infrastructures activity in the H2020-INFRAIA-2019-1 of the EU (IPERION HS Grant Agreement n. 871034)"