Cursorial ecomorphology and temporal patterns in theropod dinosaur evolution during the mid-Cretaceous

Royal Society Open Science, Journal Year: 2025, Volume and Issue: 12(1)

Published: Jan. 1, 2025

Coelurosauria, including modern birds, represents a successful group of theropod dinosaurs that established high taxonomic diversity and significant morphological modifications. In the evolutionary history this group, specialized foot morphology, arctometatarsus, evolved independently in several lineages has been considered an adaptation for cursoriality. While its functional significance extensively studied, temporal pattern parallel evolution, as well origin influencing factors, remains largely unresolved. Here, we show evolution cursorial traits, arctometatarsus hind limb proportions. Our study reveals proportional elongation distal segments preceded ornithomimosaurs oviraptorosaurs. contrast, tyrannosauroids, alvarezsaurs troodontids, tibia metatarsals occurred with acquisition arctometatarsus. The further highlights presence phylogenetic constraint outside specialization is restricted to members group. Finally, our date estimation, based on compiled patterns, demonstrates these traits emerged during mid-Cretaceous (93–120 Ma), suggesting selection locomotor performance throughout interval.

Language: Английский

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Niche partitioning shaped herbivore macroevolution through the early Mesozoic

Nature Communications, Journal Year: 2021, Volume and Issue: 12(1)

Published: May 14, 2021

Abstract The Triassic (252–201 Ma) marks a major punctuation in Earth history, when ecosystems rebuilt themselves following the devastating Permian-Triassic mass extinction. Herbivory evolved independently several times as comprising diverse assemblages of therapsids, parareptiles and archosauromorphs rose fell, leading to world dominated by dinosaurs. It was assumed that dinosaurs prevailed either through long-term competitive replacement incumbent clades or rapidly opportunistically one more extinction events. Here we use functional morphology ecology explore herbivore morphospace Early Jurassic. We identify five main guilds (ingestion generalists, prehension specialists, durophagous shearing pulpers, heavy oral processors), find generally avoided competition almost exclusively occupying different guilds. Major ecosystem remodelling triggered multiple external environmental challenges, previously dominant herbivores were marginalised newly emerging forms. Dinosaur dominance mix opportunity disaster, combined with advantage their new world.

Language: Английский

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The first edentulous ceratosaur from South America

Scientific Reports, Journal Year: 2021, Volume and Issue: 11(1)

Published: Nov. 18, 2021

Abstract The recognition of ontogenetic edentulism in the Jurassic noasaurid Limusaurus inextricabilis shed new light on dietary diversity within Ceratosauria, a stem lineage non-avian theropod dinosaurs known for peculiar craniomandibular adaptations. Until now, Ceratosauria was exclusive to adult individuals . Here, an exceptionally complete skeleton toothless ceratosaur, Berthasaura leopoldinae gen. et sp. nov., is described from Cretaceous aeolian sandstones Bauru Basin, Southern Brazil. specimen resembles by absence teeth but based unfused condition several elements (e.g., skull, vertebral column) it clearly represents ontogenetically immature individual, indicating that might never have had teeth. phylogenetic analysis performed here has nested as early-divergent Noasauridae, not closely related It most Brazilian and preserves axial series so far. Moreover, taxon exhibits many novel osteological features, uncommon theropods, unprecedented even among South American ceratosaurs. These include only jaws also premaxilla with cutting occlusal edge, slightly downturned rostral tip. This indicate B. unlikely same diet other ceratosaurs, being regarded carnivorous. As more mature specimens , been herbivorous or at least omnivorous, corroborating early evolutionary divergence noasaurids ceratosaurian bauplan disparate feeding modes.

Language: Английский

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The coevolution of rostral keratin and tooth distribution in dinosaurs

Proceedings of the Royal Society B Biological Sciences, Journal Year: 2024, Volume and Issue: 291(2015)

Published: Jan. 17, 2024

Teeth evolved early in vertebrate evolution, and their morphology reflects important specializations diet ecology among species. The toothless jaws (edentulism) extant birds likely coevolved with beak keratin, which functionally replaced teeth. However, extinct dinosaurs lost teeth multiple times independently exhibited great variation toothrow distribution rhamphotheca-like keratin structures. Here, we use rostral jawbone surface texture as a proxy for covering phylogenetic comparative models to test the influence of on Mesozoic dinosaurs. We find that evolution explains partial reduction but not jaw toothlessness. Toothrow preceded cover theropods. Non-theropod continuous toothrows despite evolving covers (e.g. some ornithischians sauropodomorphs). also show did significantly increase evolutionary rate tooth loss, further delineates antagonistic relationship between these Our results suggest had limited effect suppressing development. Independent changes development may have facilitated loss. Furthermore, strong chemical digestion, gizzard, dietary shift omnivory or herbivory alleviated selective pressures

Language: Английский

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Tooth replacement in the early-diverging neornithischian Jeholosaurus shangyuanensis and implications for dental evolution and herbivorous adaptation in Ornithischia

BMC Ecology and Evolution, Journal Year: 2024, Volume and Issue: 24(1)

Published: April 16, 2024

Abstract Background Tooth replacement patterns of early-diverging ornithischians, which are important for understanding the evolution highly specialized dental systems in hadrosaurid and ceratopsid dinosaurs, poorly known. The neornithischian Jeholosaurus , a small, bipedal herbivorous dinosaur from Early Cretaceous Jehol Biota, is an taxon ornithischian evolution, but its morphology was only briefly described previously tooth Results CT scanning six specimens representing different ontogenetic stages reveals significant new information regarding system including one or two teeth nearly all alveoli, relatively complete resorption, increase numbers alveoli during ontogeny. Reconstructions Zahnreihen indicate that pattern maxillary dentition similar to dentary with cyclical difference. rate probably 46 days, faster than most other ornithischians. During ontogeny premaxillary slows 25 days 33 daily dentine formation. Conclusions exhibits decreasing trend ontogeny, as Alligator . In phylogenetic context, fast multi-generation have evolved at least twice independently Ornithopoda, our analyses suggest members major clades exhibit adaption herbivory.

Language: Английский

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Do astigmatid teeth matter: a tribological review of cheliceral chelae in co-occuring mites from UK beehives

Experimental and Applied Acarology, Journal Year: 2024, Volume and Issue: 92(4), P. 567 - 686

Published: April 19, 2024

Abstract The dentition of the chelal moveable digit in cohabiting astigmatids from UK beehives (i.e., Carpoglyphus lactis (Linnaeus), Glycyphagus domesticus (DeGeer), and Tyrophagus putrescentiae (Schrank)) is characterised for first time using quantitative tribological measures within a 2D mechanical model. trophic function astigmatid chelae are reviewed terms macroscopic tools used by humans including hooking devices, pliers, shears, rasps saws. Comparisons to oribatid claws isopod dactyli made. overall pattern form T. not just uniformly shrunken/swollen version between other two taxa at either macro- or micro-scale. Mastication surface macro-roughness values range international Roughness Grade Numbers N5–N6. C. has low rugosity compared glycyphagid acarid (which topographically more similar match that roughness typical some coral reef surfaces). most plesiomorphic form. mastication all three species as chewing tool distinctly ornamented despite looking like bar-like beam. latter opportunities be multifunctional behaviourally than species. Little evidence any differences ‘spikiness’ ‘toothiness’ found. Some with laboratory cultured specimens found possibly suggesting where selection on may able occur. been deformed morphologically during evolution most, least. Repeated localised differentiation feature G. likely concerted changes over certain nearby locations . An impactful teeth design present but this equivocal Pockets (and extent acarid) produce foodstuff crunch forces scale tips oribatids. adapted shred (like ripsaw) grazing/shearing collecting ‘picker‘ posterior matches size Bettsia alvei hyphae which attacks hive-stored pollen. Detritus accumulated gullets through sawing action smallest observed ingested material. should less friction when moving food material hypocarnivorous ‘skim’ fluids feeding. Astigmatid do matter. commensal can avoid direct competition. Future work proposed detail.

Language: Английский

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Phenotypic Convergence Is Stronger and More Frequent in Herbivorous Fishes

Integrative and Comparative Biology, Journal Year: 2024, Volume and Issue: 64(5), P. 1467 - 1483

Published: May 9, 2024

Synopsis Constraints on phenotypic evolution can lead to patterns of convergent evolution, by limiting the “pool” potential phenotypes in face endogenous (functional, developmental) or exogenous (competition, predation) selective pressures. Evaluation convergence depends integrating ecological and morphological data within a robust, comparative phylogenetic context. The staggering diversity teleost fishes offers multitude lineages adapted for similar roles and, therefore, numerous replicated evolutionary experiments exploring convergence. However, our understanding fish feeding systems has been primarily shaped marine species, with monolithic exception freshwater cichlids. Here we use piranhas pacus (Serrasalmidae) explore different ecologies their proxies Neotropical environments. Specifically, whether is more widespread among plant-eating fishes, arising from strong constraints herbivores. Using osteological micro-computed tomographic imaging (μCT), describe major axes variation piranhas, regarding diet behaviors. Next, evaluated herbivorous niches are less labile than other dietary guilds species’ evolve at slower rate taxa. We then assess how taxa are, using three suites characters (dental, jaw, abdominal morphometrics). Ecologically, herbivory not dead end, exhibiting observed transition rates as those between carnivores omnivores. documented herbivores that have carnivores. Most instances found taxa, specifically frugivores folivores. Moreover, “complete” convergence, indicated positive metrics one morphometric dataset, were only Herbivores do appear under constrained circumstances, but this limited ability.

Language: Английский

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Non-occlusal dental microwear texture analysis of a titanosauriform sauropod dinosaur from the Upper Cretaceous (Turonian) Tamagawa Formation, northeastern Japan

Cretaceous Research, Journal Year: 2022, Volume and Issue: 136, P. 105218 - 105218

Published: March 31, 2022

Language: Английский

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Functional space analyses reveal the function and evolution of the most bizarre theropod manual unguals

Communications Biology, Journal Year: 2023, Volume and Issue: 6(1)

Published: Feb. 16, 2023

Abstract Maniraptoran dinosaurs include the ancestors of birds, and most used their hands for grasping in flight, but early-branching maniraptorans had extraordinary claws mysterious function. Alvarezsauroids short, strong arms with a stout, rock-pick-like, single functional finger. Therizinosaurians elongate fingers slender sickle-like unguals, sometimes over one metre long. Here we develop comprehensive methodological framework to investigate what functions these bizarre bony are how they formed. Our analysis includes finite element newly established functional-space also involves shape size effects an assessment function evolution. We find distinct divergence among manual unguals maniraptorans, identify complex relationship between structural strength, morphological specialisations, changes. reveals that efficient digging capabilities only emerged late-branching alvarezsauroid forelimbs, rejecting hypothesis vestigial structures like T. rex . results support statement therizinosaurians were herbivores. However, bizarre, huge Therizinosaurus such length no mechanical has been identified; suggest decorative lengthened by peramorphic growth linked increased body size.

Language: Английский

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A shift in ontogenetic timing produced the unique sauropod skull

Evolution, Journal Year: 2021, Volume and Issue: 75(4), P. 819 - 831

Published: Feb. 13, 2021

Sauropod dinosaurs include the largest terrestrial vertebrates that have ever lived. Virtually every part of sauropod body is heavily modified in association with gigantic size and associated physiological alterations. skulls are no exception: they feature elongated, telescoped facial regions connected to tilted neurocrania reoriented jaw adductor muscles. Several these cranial features been suggested be adaptations for feeding on one hand result paedomorphic transformation near base Sauropoda other. However, scarcity sauropodomorph ontogenetic series has impeded further investigation hypotheses. We re-evaluated material attributed early Anchisaurus, which our phylogenetic analyses confirm closely related sauropods. Digital assembly μCT-scanned two known specimens, a juvenile an adult, permitted us examine detailed ontogeny elements. The skull anatomy Anchisaurus distinguished by mosaic ancestral saurischian sauropod-like characters. Sauropod-like characters braincase chamber appear late ontogeny, suggesting first evolved developmental mechanism terminal addition. Shape allometric evolution demonstrate sauropodomorphs sauropods already present embryos juveniles sauropods, predisplacement-type shift timing from anchisaurian condition. propose this relaxed prior constraints morphology, allowing explore novel range phenotypes enabling specializations apparatus. occurred concert gigantism locomotory innovations.

Language: Английский

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