Skip to main content
Go to the home page of the European Commission (opens in new window)
English en
CORDIS - EU research results
CORDIS

Reconstructing the inner ear of early Pterosauria to decipher the origin of endothermy in the flying reptiles of the Mesozoic

Project description

How early dinosaurs became warm-blooded

How did pterosaurs and early dinosaurs become warm-blooded? Since fossils do not preserve metabolic information, it is difficult to reconstruct how their bodies functioned. Supported by the Marie Skłodowska-Curie Actions programme, the REPTERMO project is combining CT scans of fossil inner ears with detailed studies of living birds and reptiles in order to refine a biomechanical method known as the Thermo-Motility Index. The method links inner-ear structure to metabolic physiology and will provide the first empirically based estimates of metabolic rates in extinct reptiles. This will help to pinpoint the origins of endothermy in the Late Triassic and shed light on the evolutionary success of pterosaurs and dinosaurs. The findings are slated to shed light on how pterosaurs and dinosaurs achieved evolutionary success.

Objective

REPTERMO asks when and how endothermy evolved in pterosaurs and early dinosaurs. Flight, rapid growth and filamentous integuments point to high metabolic rates in these clades, yet direct physiological inference from fossils remains difficult. REPTERMO will refine the Thermo-Motility Index (TMI), a biomechanical framework that uses morphometrics and functional models of the semicircular canals (SCC) to infer thermal physiology. A key gap is the lack of empirical data on ampullar stereocilia in living birds and reptiles; current parameters were extrapolated from a few modern species and likely bias SCC biomechanics and downstream estimates. The project aims to: i) reconstruct via Ct scanning the inner ears from early pterosaurs (e.g. Rhamphorhynchus), lagerpetids (e.g. Ixalerpeton) and dinosauromorphs (e.g. Silesaurus), expanded by focused fieldwork and museum visits; ii) describe stereocilia via histology in selected birds (e.g. Larus fuscus, Columba livia) and reptiles (e.g. Mauremys leprosa, Crocodylus niloticus) to quantify, for the first time, the cilia deflection factor (CDF); iii) integrate the substantial dataset of reconstructed inner ear and CDF measurements to recalibrate TMI and produce robust endothermy estimates across Ornithodira. By delivering the first empirically grounded link between SCC biomechanics and metabolic state in extinct reptiles, REPTERMO will locate the origin of hypothesised endothermy in the Late Triassic and help explain the early success of pterosaurs and dinosaurs. The results will strengthen paleoenvironmental reconstructions and stimulate evolutionary concepts, while advancing CT imaging, histology and quantitative 3D analysis with cross-disciplinary value. Hosted at Instituto Superior Técnico (IST, Lisbon) in Dr Araújo’s lab, the fellowship will deepen the researcher’s skills in biomechanics, metabolic evolution and statistics, consolidating a path to research leadership in vertebrate paleobiology.

Fields of science (EuroSciVoc)

Keywords

Programme(s)

Topic(s)

Funding Scheme

HORIZON-TMA-MSCA-PF-EF - HORIZON TMA MSCA Postdoctoral Fellowships - European Fellowships

See all projects funded under this funding scheme

Call for proposal

(opens in new window) HORIZON-MSCA-2025-PF

See all projects funded under this call

Coordinator

INSTITUTO SUPERIOR TECNICO
Net EU contribution
€ 191 343,12
Address
AVENIDA ROVISCO PAIS 1
1049 001 Lisboa
Portugal
Activity type
Higher or Secondary Education Establishments
Links
Total cost
No data