Osteohistology of Enantiornithine Birds from the Lower Cretaceous Xiagou Formation

Geobios, Год журнала: 2025, Номер unknown

Опубликована: Март 1, 2025

Язык: Английский

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Growth variability, dimensional scaling, and the interpretation of osteohistological growth data

Biology Letters, Год журнала: 2021, Номер 17(11)

Опубликована: Ноя. 1, 2021

Osteohistological data are commonly used to study the life history of extant and extinct tetrapods. While recent advances have permitted detailed reconstructions growth patterns, physiology other features using these data, they most in assessments ontogenetic stage relative animals. These methods seen widespread adoption years, rapidly becoming a common component taxonomic description new fossil taxa, but often applied without close consideration sources variation present or dimensional scaling relationships that exist among different osteohistological measurements. Here, we use combination theoretical models empirical from range tetrapods review variability measurements, their resulting interpretations can be made those data. In particular, provide recommendations on usage interpretation mark spacing/zonal thickness when likely unreliable, under what conditions useful inferences for studies history.

Язык: Английский

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New giant carnivorous dinosaur reveals convergent evolutionary trends in theropod arm reduction

Current Biology, Год журнала: 2022, Номер 32(14), С. 3195 - 3202.e5

Опубликована: Июль 1, 2022

Язык: Английский

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The nature of science: The fundamental role of natural history in ecology, evolution, conservation, and education

Ecology and Evolution, Год журнала: 2023, Номер 13(10)

Опубликована: Окт. 1, 2023

There is a contemporary trend in many major research institutions to de-emphasize the importance of natural history education favor theoretical, laboratory, or simulation-based programs. This may take form removing biodiversity and field courses from curriculum sometimes subtle maligning as "lesser" branch science. Additional threats include massive funding cuts museums maintenance their collections, extirpation taxonomists across disciplines, critical under-appreciation role that data (and other forms observational data, including Indigenous knowledge) play scientific process. In this paper, we demonstrate knowledge integral any competitive science program through comprehensive review ways which they continue shape modern theory public perception We do so by reviewing how has guided disciplines ecology, evolution, conservation are crucial for effective programs policy. underscore these insights with case studies, including: understanding dynamics evolutionary radiation relies on data; methods extracting novel museum specimens; provided multi-decade programs; most logical venue creating an informed scientifically literate society. conclude recommendations aimed at students, university faculty, administrators integrating supporting mandates. Fundamentally, all interested world, but can often fall into habit abstracting our away its contexts complexities. Doing risks losing sight entire vistas new questions over-emphasis simulated overly controlled studies.

Язык: Английский

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Palaeoecological deductions from osteohistology

Biology Letters, Год журнала: 2023, Номер 19(8)

Опубликована: Авг. 1, 2023

Palaeoecological deductions are vital for understanding the evolution and diversification of species within prehistoric environments. This review highlights multitude ways in which microanatomy microscopic structure bones enables palaeoecological deductions. The occurrence growth marks is discussed, their usefulness deducing ontogenetic status age individuals considered, as well how such permit assessment dynamics species. Here osteohistology shown to provide insight into past populations, ecological relationships between individuals. In addition, response trauma, disease moulting considered. Finally, I explore can give ecomorphological adaptations, filter feeding, probe feeding saltatorial locomotion. Methodological advances three-dimensional microtomography synchrotron scanning bodes future studies despite some compromises terms tissue identity, circumvents crucial issue destructive analyses.

Язык: Английский

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Growing with dinosaurs: a review of dinosaur reproduction and ontogeny

Biology Letters, Год журнала: 2025, Номер 21(1)

Опубликована: Янв. 1, 2025

Since the start of twenty-first century, there has been a notable increase in annual publications focusing on dinosaur reproduction and ontogeny with researchers using these data to address range macroevolutionary questions about dinosaurs. Ontogeny, which is closely tied osteological morphological variation, impacts several key research areas, such as taxonomic diversity, population dynamics, palaeoecology, macroevolution, well physiological reproductive factors driving ecological success. While broad studies have significantly advanced our understanding evolution, they also revealed important challenges areas needing further investigation. In this review, we aim outline some major linked ontogeny, namely biology, osteohistological growth strategies, variation link between macroevolution. We offer recommendations for best practices promising future directions. These include increasing sample sizes through fieldwork exhaustive use pre-existing fossil collections, micro-computed tomography (μCT) scanning methods dataset non-destructive manner, methodical collection reposition μCT scan data, assessing ontogenetic maturity, establishing consistency terminology building comprehensive extant comparative datasets.

Язык: Английский

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

Journal of Anatomy, Год журнала: 2025, Номер unknown

Опубликована: Янв. 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.

Язык: Английский

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A fast start: Evidence of rapid growth in Trialestes romeri, an early Crocodylomorpha from the Upper Triassic continental beds of Argentina based on osteohistological analyses

Journal of Anatomy, Год журнала: 2025, Номер unknown

Опубликована: Янв. 31, 2025

The palaeobiology aspects of early Crocodylomorpha during their origin in the Triassic are poorly known, despite occupying an important palaeoecological role continental environments. In this study, we report microstructural features appendicular bones two specimens Trialestes romeri, a non-Crocodyliformes from Upper NW Argentina. Our goals to infer life history (i.e. age estimation and maturity events), inter-elemental variation growth dynamics within phylogenetic framework. samples include humerus ulna holotype (PVL 2561) femur referred specimen 3889). All elements mostly composed by fibrolamellar complex with variable distribution parallel-fibred bone cortex. Furthermore, they possess uniform homogeneous vascularisation, formed mainly laminar pattern. PVL 2561 records lines arrested (LAGs) no cyclical marks were registered ulna. Meanwhile, 3889 exhibit single LAG. Hence, slight disparate is reported both individuals. absence external fundamental system (EFS) homogenous matrix vascularisation suggest that did not attain sexual somatic maturity. Overall, histological T. romeri indicate rapid rate just like other crocodylomorphs (Terrestrisuchus, Saltoposuchus), whereas others rather moderate (Crocodylomorpha indet. BP/1/8484 specimen) or slower (Hesperosuchus) rate. These findings reveal rates widely present among occurrence evolutionary might it plesiomorphic condition.

Язык: Английский

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Osteohistology of the unusually fast‐growing theropod dinosaur Ceratosaurus

Journal of Anatomy, Год журнала: 2025, Номер unknown

Опубликована: Фев. 5, 2025

Abstract Ceratosaurus is a large‐bodied non‐avian theropod dinosaur known from the Upper Jurassic Morrison Formation of North America and remarkable both for its exceptionally fast annual growth rate status as only currently with postcranial osteoderms. We describe osteohistology three hind limb bones, two dorsal ribs, one osteoderm representing four individuals . In addition to describing tissues these we compared rates in our sample those five other ceratosaurians. fit seven models specimens results best‐fit model(s) ceratosaurians ( Masiakasaurus knopfleri Majungasaurus crenatissimus ) which sufficient data were available. The bone tissue limbs highly vascularized, dense plexiform or reticular vascular complexes alternating strips parallel woven‐fibered matrix. Few lines arrested recorded prior achieving asymptotic body size. Both sampled ribs are remodeled, small portions primary visible each section, revealing parallel‐fibered sparse osteons. contain numerous throughout cortex that allowed more accurate estimates individual age when paired limbs. composed core large Haversian canals perimeter lamellar Sharpey's fibers along internal surface bone. Multiple LAGs also present within exterior margins. Maximum on average nine‐fold faster than Our lacks juveniles so confidence inferred limited. Thus, begin constrain patterns, averaged all possessed an Akaike Information Criterion score corrected size (AICc) 10 lowest scoring model. found monomolecular model exhibited AICc value, von Bertalanffy Gompertz possessing values units it. contrast, logistic confidently selected , respectively. Irrespective model, maximum relative several‐fold greater Majungasaurus. histological life history support evolutionary trend towards prolonged development Ceratosauria through time.

Язык: Английский

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Evolution of growth strategy in alligators and caimans informed by osteohistology of the late Eocene early‐diverging alligatoroid crocodylian Diplocynodon hantoniensis

Journal of Anatomy, Год журнала: 2025, Номер unknown

Опубликована: Фев. 9, 2025

Among living crocodylians, alligatoroids exhibit a wide range of body sizes and biogeographic distribution that spans tropical-to-subtropical climates. The fossil record alligatoroids, however, reveals even greater diversity, including multiple examples gigantism broader extends into polar latitudes. Osteohistological studies on extant show alligators caimans both seasonal growth, with roughly comparable growth rates. However, diverged from one another over 60 million years ago; the dearth extinct makes it unclear if shared condition in taxa reflects convergent responses to rapid climatic changes recent past or represents ancestral alligatoroids. Additionally, sample are often limited two individuals, especially obscuring any intraspecific variation present. To address this uncertainty, we conducted largest monospecific osteohistological study an crocodylian date, based nine femora, providing unique insight early-diverging alligatoroid Diplocynodon hantoniensis late Eocene UK. bone microanatomy D. shows moderate compactness, well-defined medullary cavity, features generally consistent those Samples vary greatly along continuum degree remodelling vascularity, highlighting importance evaluating limitations basing histological assessments singleton samples. Ontogenetic assessment indicates our captures skeletally immature mature approximately corresponding femoral size, but notable exceptions possibly driven by sexual dimorphism. Body size estimates for (1.2-3.4 m) fall within typical American (Alligator mississippiensis). Reconstruction cyclical marks similar overall rate between A. mississippiensis. As more generally, is determinate, seasonally-controlled growth. Femoral circumference scales positively length hantoniensis, demonstrating allometry This differs some other crocodylians (e.g. Crocodylus niloticus johnstoni) suggests conservation allometric relationships in-depth look early diverging seasonality rates present members were established near base clade. Furthermore, highlights larger samples singular species order capture potential when making clade-wide interpretations.

Язык: Английский

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