Unique internal anatomy of vertebrae as a key factor for neck elongation in Triassic archosauromorphs DOI Creative Commons
Adam Rytel, Dawid Surmik, Tomasz Szczygielski

et al.

Zoological Journal of the Linnean Society, Journal Year: 2024, Volume and Issue: 202(3)

Published: Oct. 14, 2024

Abstract The Triassic was a key period in the evolution of vertebrates, and reptiles particular, giving rise to plethora successful lineages, some which are still extant. One groups that flourished during early Mesozoic were tanysaurians (Archosauromorpha: Tanysauria). They had elongate neck vertebrae genera reached extreme proportions. Here, we provide first comprehensive description internal structure these extraordinary elements, focusing on famously bizarre Tanystropheus. Through computed tomography sectioning, able reveal intriguing features comparable those seen pterosaurs birds. However, contrary what see pneumatic bones, cervicals contain singular voluminous cavity. This results cylindrical vertebrae, likely provided durability, while contributing less weight neck. These insights relevant for better understanding unique anatomy among tetrapods, evolved as result very strict selection particular function. Importantly, our findings demonstrate major modifications not derived avemetatarsalians (pterosaurs dinosaurs), but more widespread reptiles.

Language: Английский

The influence of soft tissue volume on estimates of skeletal pneumaticity: implications for fossil archosaurs DOI Creative Commons
Maria Grace Burton, Juan Benito,

Kirsty Mellor

et al.

Philosophical Transactions of the Royal Society B Biological Sciences, Journal Year: 2025, Volume and Issue: 380(1920)

Published: Feb. 27, 2025

Air space proportion (ASP), the volume fraction in bone that is occupied by air, frequently applied as a measure for quantifying extent of skeletal pneumaticity extant and fossil archosaurs. Nonetheless, ASP estimates rely on key assumption: soft tissue mass within pneumatic bones negligible, an assumption has rarely been explicitly acknowledged or tested. Here, we provide first comparisons between estimated air (where internal cavity assumed to be completely air-filled) true (ASPt, where tissues present cavities fresh specimens are considered). Using birds model archosaurs exhibiting postcranial pneumaticity, find ASPt significantly lower than ASP, raising important consideration should investigations evolution bulk density extinct archosaurs, well volume-based archosaur body mass. We advocate difference studies seeking quantify avoid risk systematically overestimating composed air. This article part theme issue ‘The biology avian respiratory system’.

Language: Английский

Citations

3

Whence the birds: 200 years of dinosaurs, avian antecedents DOI Creative Commons
Daniel J. Field, Maria Grace Burton, Juan Benito

et al.

Biology Letters, Journal Year: 2025, Volume and Issue: 21(1)

Published: Jan. 1, 2025

Among the most revolutionary insights emerging from 200 years of research on dinosaurs is that clade Dinosauria represented by approximately 11 000 living species birds. Although origin birds among has been reviewed extensively, recent have witnessed tremendous progress in our understanding deep evolutionary origins numerous distinctive avian anatomical systems. These advances enabled exciting new fossil discoveries, leading to an ever-expanding phylogenetic framework with which pinpoint characteristic features. The present review focuses four notable systems whose Mesozoic history greatly clarified discoveries: brain, kinetic palate, pectoral girdle and postcranial skeletal pneumaticity.

Language: Английский

Citations

1

A sauropod dinosaur with an unusually thin ilium DOI
Jack A. Cooper

Historical Biology, Journal Year: 2025, Volume and Issue: unknown, P. 1 - 2

Published: April 28, 2025

Language: Английский

Citations

0

Variation in the postcranial pneumaticity in derived titanosaurs (Dinosauria: Sauropoda) DOI
Virginia Zurriaguz

Historical Biology, Journal Year: 2024, Volume and Issue: unknown, P. 1 - 15

Published: July 24, 2024

Currently, only birds have a pneumatic system, but in the past, this was common among several ornithodirans. Within Titanosauria, it saltasaurines that showed high degree of postcranial pneumaticity. The objective work is analysing extent pneumaticity and compare with other derived titanosaurs. To carry out work, presacral vertebrae, dorsal ribs, scapulae, coracoids ilia were analysed. vertebrae present pneumatisation highly variable distribution foramina, some 'foramina zones', there homoplastic pattern pneumaticity: presence foramina connected to camellated tissue. With respect ilia, tissue recorded all taxa. Instead, scapulae coracoids, Saltasaurus they cannot be pneumatised Neuquensaurus. Comparing titanosaurs, we observe are zones' for caudal vertebrae. It also possible establish ribs has conservative pattern, not Saurischia clade, frequent Lithostrotia even outside, rebbachisaurs.

Language: Английский

Citations

3

The influence of soft tissue volume on estimates of skeletal pneumaticity: implications for fossil archosaurs DOI Creative Commons
Maria Grace Burton, Juan Benito,

Kirsty Mellor

et al.

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2024, Volume and Issue: unknown

Published: Oct. 11, 2024

Abstract Air space proportion (ASP), the volume fraction in bone occupied by air, is frequently applied as a measure for quantifying extent of skeletal pneumaticity extant and fossil archosaurs. Nonetheless, ASP estimates rely on key assumption: that soft tissue mass within pneumatic bones negligible, an assumption has rarely been explicitly acknowledged or tested. Here, we provide first comparisons between estimated air (where internal cavity assumed to be completely air-filled) true (ASPt, where tissues present cavities fresh specimens are considered). Using birds model archosaurs exhibiting postcranial pneumaticity, find ASPt significantly lower than ASP, raising important consideration should investigations evolution bulk density extinct archosaurs, well volume-based archosaur body mass. We advocate difference studies seeking quantify avoid risk systematically overestimating composed air.

Language: Английский

Citations

2

Unique internal anatomy of vertebrae as a key factor for neck elongation in Triassic archosauromorphs DOI Creative Commons
Adam Rytel, Dawid Surmik, Tomasz Szczygielski

et al.

Zoological Journal of the Linnean Society, Journal Year: 2024, Volume and Issue: 202(3)

Published: Oct. 14, 2024

Abstract The Triassic was a key period in the evolution of vertebrates, and reptiles particular, giving rise to plethora successful lineages, some which are still extant. One groups that flourished during early Mesozoic were tanysaurians (Archosauromorpha: Tanysauria). They had elongate neck vertebrae genera reached extreme proportions. Here, we provide first comprehensive description internal structure these extraordinary elements, focusing on famously bizarre Tanystropheus. Through computed tomography sectioning, able reveal intriguing features comparable those seen pterosaurs birds. However, contrary what see pneumatic bones, cervicals contain singular voluminous cavity. This results cylindrical vertebrae, likely provided durability, while contributing less weight neck. These insights relevant for better understanding unique anatomy among tetrapods, evolved as result very strict selection particular function. Importantly, our findings demonstrate major modifications not derived avemetatarsalians (pterosaurs dinosaurs), but more widespread reptiles.

Language: Английский

Citations

0