Multiple pathways to herbivory underpinned deep divergences in ornithischian evolution

Current Biology, Год журнала: 2023, Номер 33(3), С. 557 - 565.e7

Опубликована: Янв. 5, 2023

The extent to which evolution is deterministic a key question in biology,1,2,3,4,5,6,7,8,9 with intensive debate on how adaptation6,10,11,12,13 and constraints14,15,16 might canalize solutions ecological challenges.4,5,6 Alternatively, unique adaptations1,9,17 phylogenetic contingency1,3,18 may render fundamentally unpredictable.3 Information from the fossil record critical this debate,1,2,11 but performance data for extinct taxa are limited.7 This knowledge gap significant, as general morphology be poor predictor of biomechanical performance.17,19,20 High-fiber herbivory originated multiple times within ornithischian dinosaurs,21 making them an ideal clade investigating evolutionary responses similar pressures.22 However, previous modeling studies crania17,23,24,25 have not compared early-diverging spanning independent acquisitions herbivory. Here, we perform finite-element analysis skull five members major clades characterize morphofunctional pathways Results reveal limited functional convergence among clades, each instead achieving comparable performance, terms reconstructed patterns magnitudes functionally induced stress, through different adaptations feeding apparatus. Thyreophorans compensated plesiomorphic low increased absolute size, heterodontosaurids expanded jaw adductor muscle volume, ornithopods system efficiency, ceratopsians combined these approaches. These distinct challenges Ornithischia underpinned success diverse clade. Furthermore, resolution equivalent problems single macroevolutionary time demonstrates that phenotypic necessarily predictable, arising interplay adaptation, innovation, contingency, constraints.1,2,3,7,8,9,18.

Язык: Английский

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The coevolution of rostral keratin and tooth distribution in dinosaurs

Proceedings of the Royal Society B Biological Sciences, Год журнала: 2024, Номер 291(2015)

Опубликована: Янв. 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

Язык: Английский

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Morphological disparity and structural performance of the dromaeosaurid skull informs ecology and evolutionary history

BMC Ecology and Evolution, Год журнала: 2024, Номер 24(1)

Опубликована: Апрель 16, 2024

Abstract Non-avialan theropod dinosaurs had diverse ecologies and varied skull morphologies. Previous studies of cranial morphology mostly focused on higher-level taxa or characteristics associated with herbivory. To better understand morphological disparity function within carnivorous families, here we focus the Dromaeosauridae, ‘raptors’ traditionally seen as agile hunters. We applied 2D geometric morphometrics to quantify shape, performed mechanical advantage analysis assess efficiency bite force transfer, finite element examine strain distribution in during biting. find that dromaeosaurid was less disparate than most non-avialan groups. Their skulls show a continuum form between those are tall short flat long. hypothesise this narrower indicates developmental constraint observed some mammalian families. Mechanical Dromaeosaurus albertensis Deinonychus antirrhopus were adapted for relatively high forces, while Halszkaraptor escuilliei speed, other dromaeosaurids intermediate forces speeds. Finite regions consistent families but differ them. Average levels do not follow any phylogenetic pattern, possibly due ecological convergence distantly-related taxa. Combining our new morphofunctional data re-evaluation previous evidence, piscivorous reconstructions be unlikely, instead suggest an invertivorous diet possible adaptations feeding murky water low-visibility conditions. support being taking large vertebrate prey, its is resistant dromaeosaurids. Given recovery resistance Velociraptor mongoliensis , which believed have regularly engaged scavenging behaviour, higher taxon may reflect greater reliance rather fresh kills. Comparisons troodontid Gobivenator gracile rostrum like ancestral their closest common ancestor (Deinonychosauria) robust rostra derived condition. also displays jaw lower examined dromaeosaurids, given hypothesised divergence troodontids from it unclear group, if either, represents Future work extending sampling would therefore invaluable provide much needed context origin early birds. This study illustrates how shape functional metrics can discern ecology at taxonomic identify variants feeding.

Язык: Английский

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Reconstruction of feeding behaviour and diet in Devonian ctenacanth chondrichthyans using dental microwear texture and finite element analyses

Royal Society Open Science, Год журнала: 2025, Номер 12(1)

Опубликована: Янв. 1, 2025

Devonian ctenacanth chondrichthyans reached body sizes similar to modern great white sharks and therefore might have been apex predators of the seas. However, very little is known about diet feeding behaviours these large ancestral sharks. To reconstruct their ecological properties, teeth Famennian (Late Devonian) chondrichthyan Ctenacanthus concinnus from Anti-Atlas, Morocco, were analysed. The show strong tooth wear with deep horizontal as well vertical scratches. Dental microwear texture analysis, a well-established method for reconstruction commonly used in terrestrial vertebrates, was applied first time, our knowledge, Palaeozoic vertebrates this study. Furthermore, finite element analysis performed test biomechanical properties teeth. By combining both analyses, palaeoenvironmental data morphology, we demonstrate that results only one can be insufficient misleading. most likely an opportunistic feeder like many Direct evidence analyses suggest fed on ectocochleate cephalopods, other further using combination head movements including lateral shaking cut prey items.

Язык: Английский

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Morphology of the maxilla informs about the type of predation strategy in the evolution of Abelisauridae (Dinosauria: Theropoda)

Scientific Reports, Год журнала: 2025, Номер 15(1)

Опубликована: Март 6, 2025

Abelisauridae is a clade of theropods distinguished by short, ornamented skulls and strongly reduced forelimbs. They represented the most abundant predatory dinosaurs in Gondwana during Cretaceous. Bolstered biomechanical studies, morphology skull vertebral column abelisaurids, have led researchers to hypothesize that Late Cretaceous forms were "specialized hunters." Here, we use abelisaurid maxilla test inclusion Lower Spectrovenator within specialized hunter category. Additionally, analyze diversity disparity macroevolutionary context. We quantified maxillary shape 17 taxa using 2D geometric morphometrics analyzed different evolutionary scenarios trends with phylogenetic comparative methods. The results all analyses (phylogenetic ordination methods, Z, R2 comparison generalized least squares, model selection, estimated taxa-removal analysis) suggest specialization appeared Early Cretaceous, revealing abelisaurids can be considered specialist hunters. High levels morphological occurred shortly after Cenomanian-Turonian faunistic turnover, which involved drastic changes South American terrestrial faunal assemblages. Moreover, high rates change support shift ecological pressures or socio-sexual mechanisms, main drivers evolution rostrum. Our study invites more osteological elements under quantitative framework our comprehensively.

Язык: Английский

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Jaw biomechanics of Troodontidae and their implications for the palaeobiology of this lineage of bird-like theropod dinosaurs

Lethaia, Год журнала: 2025, Номер 58(1), С. 1 - 12

Опубликована: Фев. 20, 2025

Язык: Английский

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Direct evidence of carnivory in the early-diverging Alvarezsaurian <i>Bannykus</i>

The Innovation Geoscience, Год журнала: 2025, Номер unknown, С. 100143 - 100143

Опубликована: Янв. 1, 2025

<p>A dietary shift from carnivory to insectivory has been proposed explain the morphological evolution of alvarezsaurians, particularly adaptive manual digital reduction and body size miniaturization. However, based solely on shifts, this hypothesis lacks direct evidence support either or insectivory. Here, we present first for derived intestinal contents Early Cretaceous <i>Bannykus wulatensis</i>. Our analysis revealed significantly higher levels calcium phosphorus in compared surrounding sandstone. Scanning electron microscopy identified hard tissue debris possible soft tissues surrounded by phosphatized bacteria tightly packed hollow microspheres, suggesting that were strongly pseudomorphed microbes during fossilization. Raman spectroscopy showed characteristic peaks indicative bone-derived material, consistent with contents. results suggest <i>Bannykus</i> had a carnivorous diet strong chemical digestion, which likely compensated its delicate cranial structures small teeth. These imply if occurred, it took place later alvarezsaurian evolution, probably coinciding size.</p>

Язык: Английский

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One step further in biomechanical models in palaeontology: a nonlinear finite element analysis review

PeerJ, Год журнала: 2022, Номер 10, С. e13890 - e13890

Опубликована: Авг. 8, 2022

Finite element analysis (FEA) is no longer a new technique in the fields of palaeontology, anthropology, and evolutionary biology. It nowadays well-established within virtual functional-morphology toolkit. However, almost all works published these have only applied most basic FEA tools i.e ., linear materials static structural problems. Linear approximations are commonly used because they computationally less expensive, error associated with assumptions can be accepted. Nonetheless, nonlinearities natural to biomechanical models especially when modelling soft tissues, establish contacts between separated bones or inclusion buckling results. The aim this review to, firstly, highlight usefulness non-linearities secondly, showcase tool researchers that work functional morphology biomechanics, as improve their by widening possible applications topics currently not palaeontology anthropology.

Язык: Английский

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

Communications Biology, Год журнала: 2023, Номер 6(1)

Опубликована: Фев. 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.

Язык: Английский

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Dots on a screen: The past, present, and future of morphometrics in the study of nonavian dinosaurs

The Anatomical Record, Год журнала: 2023, Номер 306(7), С. 1896 - 1917

Опубликована: Март 15, 2023

Using morphometrics to study nonavian dinosaur fossils is a practice that predates the origin of word "dinosaur." By 1970s, linear had become established as valuable tool for analyzing intra- and interspecific variation in dinosaurs. With advent more recent techniques such geometric advanced statistical approaches, morphometric analyses dinosaurs have proliferated, granting unprecedented insight into many aspects their biology evolution. I outline past, present, future applied zeroing on five paleobiology where has been widely utilized advance our knowledge: systematics, sexual dimorphism, locomotion, macroevolution, trackways. Morphometric methods are especially susceptible taphonomic distortion. As such, impact distortion original fossil shape discussed current quantifying accounting with goal reducing noise biological signal ratio. Finally, paleobiologists move "virtual paleobiology" framework, whereby digital renditions captured via photogrammetry computed tomography. These primary data form basis three-dimensional (3D) along slew other forms analyses. 3D specimen part extended help democratize paleobiology, unlocking from physical museum making available researchers across world.

Язык: Английский

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