A path to gigantism: Three‐dimensional study of the sauropodomorph limb long bone shape variation in the context of the emergence of the sauropod bauplan DOI Creative Commons
Rémi Lefebvre, Alexandra Houssaye, Heinrich Mallison

et al.

Journal of Anatomy, Journal Year: 2022, Volume and Issue: 241(2), P. 297 - 336

Published: March 6, 2022

Sauropodomorph dinosaurs include the largest terrestrial animals that ever lived on Earth. The early representatives of this clade were, however, relatively small and partially to totally bipedal, conversely gigantic quadrupedal sauropods. Although sauropod bauplan is well defined, notably by acquisition columnar limbs, evolutionary sequence leading its emergence remains debated. Here, we aim tackle episode investigating shape variation in six limb long bones for first time using three-dimensional geometric morphometrics. morphological features forelimb zeugopod related tend appear abruptly, whereas pattern more gradual hindlimb bones. stylopod show same as their respective zeugopods. abrupt questions locomotor abilities non-sauropodan sauropodomorphs inferred quadrupeds. Features characterizing sauropods corroborate a view locomotion mainly based retraction. An allometric investigation accordance with size highlight differences bone allometries between sauropodomorphs. These correspond an unexpected robustness decrease trend zeugopod. In addition be proportionally gracile than sauropodomorphs, may have relied architecture increase, rather general robustness, deal role weight-bearing.

Language: Английский

Whole‐body endothermy: ancient, homologous and widespread among the ancestors of mammals, birds and crocodylians DOI
Gordon C. Grigg, Julia Nowack, J. Eduardo P. W. Bicudo

et al.

Biological reviews/Biological reviews of the Cambridge Philosophical Society, Journal Year: 2021, Volume and Issue: 97(2), P. 766 - 801

Published: Dec. 10, 2021

The whole-body (tachymetabolic) endothermy seen in modern birds and mammals is long held to have evolved independently each group, a reasonable assumption when it was believed that its earliest appearances arose many millions of years apart. That consistent with current acceptance the non-shivering thermogenesis (NST) component regulatory body heat originates differently group: from skeletal muscle brown adipose tissue (BAT) mammals. However, BAT absent monotremes, marsupials, eutherians, all endotherms. Indeed, recent research implies BAT-driven NST originated more recently biochemical processes driving birds, ancestors both may be similar, deriving controlled 'slippage' Ca

Language: Английский

Citations

74
Review of the fossil record of early dinosaurs from South America, and its phylogenetic implications DOI
Fernando E. Novas, Federico L. Agnolín, Martín D. Ezcurra

et al.

Journal of South American Earth Sciences, Journal Year: 2021, Volume and Issue: 110, P. 103341 - 103341

Published: April 29, 2021

Language: Английский

Citations

67
A Giant Dinosaur from the Earliest Jurassic of South Africa and the Transition to Quadrupedality in Early Sauropodomorphs DOI Creative Commons

Blair W. McPhee,

Roger Benson, Jennifer Botha

et al.

Current Biology, Journal Year: 2018, Volume and Issue: 28(19), P. 3143 - 3151.e7

Published: Sept. 27, 2018

Language: Английский

Citations

82
A chronostratigraphic framework for the upper Stormberg Group: Implications for the Triassic-Jurassic boundary in southern Africa DOI
Emese M. Bordy, Miengah Abrahams, Glenn R. Sharman

et al.

Earth-Science Reviews, Journal Year: 2020, Volume and Issue: 203, P. 103120 - 103120

Published: Feb. 19, 2020

Language: Английский

Citations

69
Ontogenetic changes in the body plan of the sauropodomorph dinosaur Mussaurus patagonicus reveal shifts of locomotor stance during growth DOI Creative Commons
Alejandro Otero, Andrew R. Cuff, Vivian Allen

et al.

Scientific Reports, Journal Year: 2019, Volume and Issue: 9(1)

Published: May 20, 2019

Abstract Ontogenetic information is crucial to understand life histories and represents a true challenge in dinosaurs due the scarcity of growth series available. Mussaurus patagonicus was sauropodomorph dinosaur close origin Sauropoda known from hatchling, juvenile mature specimens, providing sufficiently complete ontogenetic reconstruct general patterns ontogeny. Here, order quantify how body shape its relationship with locomotor stance (quadruped/biped) changed ontogeny, (~1 year old) adult (8+ years individuals were studied using digital models. Our results show that rapidly grew about 60 g at hatching ~7 kg one old, reaching >1000 adulthood. During this time, body’s centre mass moved position mid-thorax more caudal nearer pelvis. We infer these changes reflect shift quadrupedalism bipedalism occurred early ontogeny . study indicates relative development tail neck influential determining Sauropodomorpha during challenging previous studies, which have emphasized influence hindlimb vs. forelimb lengths on stance.

Language: Английский

Citations

55
Africa’s oldest dinosaurs reveal early suppression of dinosaur distribution DOI
Christopher T. Griffin, Brenen M. Wynd,

Darlington Munyikwa

et al.

Nature, Journal Year: 2022, Volume and Issue: 609(7926), P. 313 - 319

Published: Aug. 31, 2022

Language: Английский

Citations

36
Extinction of herbivorous dinosaurs linked to Early Jurassic global warming event DOI Open Access
Diego Pol, Jahandar Ramezani, Kevin Leonel Gomez

et al.

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2020, Volume and Issue: 287(1939), P. 20202310 - 20202310

Published: Nov. 18, 2020

Sauropods, the giant long-necked dinosaurs, became dominant group of large herbivores in terrestrial ecosystems after multiple related lineages extinct towards end Early Jurassic (190–174 Ma). The causes and precise timing this key faunal change, as well origin eusauropods (true sauropods), have remained ambiguous mainly due to scarce dinosaurian fossil record time. sedimentary successions Cañadón Asfalto Basin central Patagonia (Argentina) document critical interval dinosaur evolution. Here, we report a new with nearly complete skull that is oldest eusauropod known date provide high-precision U–Pb geochronology constrains time rise Patagonia. We show dominance was established massive magmatic event impacting southern Gondwana (180–184 Ma) coincided severe perturbations climate drastic decrease floral diversity characterized by conifers small scaly leaves. Floral records from other regions suggest these were global changes impacted during Toarcian warming formed part second-order mass extinction event.

Language: Английский

Citations

47
Re-assessment of the Late Jurassic eusauropod Mamenchisaurus sinocanadorum Russell and Zheng, 1993, and the evolution of exceptionally long necks in mamenchisaurids DOI
Andrew Moore, Paul M. Barrett, Paul Upchurch

et al.

Journal of Systematic Palaeontology, Journal Year: 2023, Volume and Issue: 21(1)

Published: Jan. 1, 2023

The sauropod genus Mamenchisaurus, from the Late Jurassic–Early Cretaceous of East Asia, has a convoluted taxonomic history. Although included in first cladistic analysis sauropods, only recently monophyly and anatomical diversity many penecontemporaneous Asian eusauropods, been evaluated critically. Here, we re-describe holotype specimen M. sinocanadorum. original diagnosis is no longer adequate, identify several autapomorphies that support validity this species, including an elongate external mandibular fenestra distinctive pneumatic structures on cervical centra. We incorporate new data into phylogenetic character matrix also includes Bellusaurus Daanosaurus, both which are known juvenile material often hypothesized to be neosauropods (or close relatives thereof). recover all species Mamenchisaurus as part radiation predominantly Middle–Late Jurassic but non-monophyletic, underscoring need for further systematic revision mamenchisaurid taxonomy. Analyses score ontogenetically variable characters ambiguously Daanosaurus mamenchisaurids, hypothesis supported by features unique mamenchisaurids or exhibit little homoplasy, anteriorly bifurcate ribs. Finally, computed-tomography reveals extensive vertebral pneumaticity sinocanadorum comparable largest updated scaling analyses imply neck over 14 m long, rivalling estimates other exceptionally long-necked sauropods. Previous work suggested elongated ribs particularly sauropods such stabilized limiting its mobility. Given extent responds dynamically bone's habitual loading, propose long – structural modifications limited flexibility promoted evolution increasingly necks producing more predictable biomechanical milieu amenable increased pneumatization.

Language: Английский

Citations

14
Ten more years of discovery: revisiting the quality of the sauropodomorph dinosaur fossil record DOI Creative Commons
Daniel D. Cashmore, Philip D. Mannion, Paul Upchurch

et al.

Palaeontology, Journal Year: 2020, Volume and Issue: 63(6), P. 951 - 978

Published: July 18, 2020

Abstract Spatiotemporal changes in fossil specimen completeness can bias our understanding of a group's evolutionary history. The quality the sauropodomorph record was assessed decade ago, but number valid species has since increased by 60%, and 17% taxa from that study have undergone taxonomic revision. Here, we assess how 10 years additional research changed outlook on record. We quantified all 307 currently considered using skeletal metric, which calculates proportion complete skeleton preserved for each taxon. Taxonomic stratigraphic age revisions, rather than new species, are drivers most significant differences between current results those previous assessment. No statistical appeared when use dataset to generate temporal curves based solely known 2009 or 1999. now observe severe drop mean values across Jurassic–Cretaceous boundary never recovers pre‐Cretaceous levels. Explaining this pattern is difficult, as find no convincing evidence it related environmental preferences body size changes. Instead, might result from: (1) reduction terrestrial preservation space due sea level rise; (2) ecological specificities relatively high diagnosability Cretaceous species; and/or (3) sampling newly explored sites with many previously unknown taxa. Revisiting patterns manner allows us test longevity conclusions made quantitative studies.

Language: Английский

Citations

39
Triassic sauropodomorph dinosaurs from South America: The origin and diversification of dinosaur dominated herbivorous faunas DOI
Diego Pol, Alejandro Otero, Cecilia Apaldetti

et al.

Journal of South American Earth Sciences, Journal Year: 2021, Volume and Issue: 107, P. 103145 - 103145

Published: Jan. 13, 2021

Language: Английский

Citations

32