Intraskeletal histovariability and skeletochronology in an ornithopod dinosaur from the Maestrazgo Basin (Teruel, Spain)

Journal of Anatomy, Journal Year: 2025, Volume and Issue: unknown

Published: Jan. 28, 2025

Abstract Ornithopods are an extinct group of dinosaurs that were particularly abundant and diverse in the Cretaceous Iberian Peninsula, whose abundance Maestrazgo Basin has allowed numerous taxa to be identified over last decade. Many these fossil remains still taxonomically indeterminate require a more detailed study on both macroscopic microscopic scale. In this contribution, osteohistological analysis is carried out partial skeleton—composed five incomplete vertebrae, two dorsal ribs, ischium, fibula, tibia—found province Aliaga (Teruel, NE Spain). We progressive slowdown tissue apposition variation type growth marks generated every bone, allowing precise identification ontogenetic stage specimen as subadult individual. The skeletochronological correlation between different elements also suggests reached sexual maturity at around seven years age died nine twelve age. Likewise, usefulness three‐front model proven for first time ornithopod dinosaur, tool analysing histology expressed by bone single inferring their potential. Comparison with other reveals great variability each element shows depending taxon analysed, which prevents us from determining suitable studying skeletochronology any taxon.

Language: Английский

Osteohistological analysis of metatarsals reveals new information on pathology and life history of troodontids from the Campanian Dinosaur Park Formation, Alberta, Canada

Journal of Anatomy, Journal Year: 2025, Volume and Issue: unknown

Published: April 19, 2025

Abstract Troodontidae is a family of small‐bodied theropods known predominantly from Asia but are comparatively scarce in North America. In the Dinosaur Park Formation (DPF) Alberta, Canada, they isolated material, precluding taxonomic and ontogenetic precision for this clade. Previously never sampled histologically within DPF, here we attempt to fill gaps our knowledge about life histories clade formation by surveying metatarsals, which among most abundant identifiable troodontid elements DPF. We 11 metatarsals (three metatarsal IIs, three IIIs five IVs) varying sizes included pathological individuals describe microanatomy both healthy determine status each element graph their pattern growth. Osteohistology reveals that grew remodelled asymmetrically cortex, ceasing growth remodelling primarily along articular surfaces entheses. Pathological ranged displaying features response localised stress (chronic callus avulsion/chip fracture) extreme modification trauma inflammation at distal joint. Only latter appeared be related overall growth, suggesting condition either developed early stunted or another underlying cause was responsible resulting observed. Overall, tracking specimens there least two trajectories DPF differentiated timing major spurts plateaus. Whether represents sexual dimorphism, diversity, form variation warrants further investigation.

Language: Английский