Results 121 to 130 of about 173 (164)

Broadening the semiaquatic scene: Quantification of long bone microanatomy across pinnipeds

The Anatomical Record, EarlyView.
Abstract Investigations of bone microanatomy are commonly used to explore lifestyle strategies in vertebrates. While distinct microanatomical limb bone features have been established for exclusively aquatic and terrestrial lifestyles, identifying clear patterns for the semiaquatic lifestyle remains more challenging.
Apolline Alfsen, Christian de Muizon, Olivier Lambert, Giovanni Bianucci, Antonia R. Kaffler, Matthew R. McCurry, Alexandra Houssaye, Rafael M. Varas‐Malca, Rodolfo Salas‐Gismondi, Oliver Hampe, Eli Amson   +10 more
wiley   +1 more source

From armadillos to sloths: Patterns and variations in xenarthran coronary anatomy

The Anatomical Record, EarlyView.
Abstract Species of the superorder Xenarthra play a vital ecological role in the Neotropics. Despite their evolutionary significance, anatomical studies on their coronary circulation remain scarce. This study investigated the coronary anatomy of 82 hearts from nine Xenarthra species across the Dasypodidae, Myrmecophagidae, and Bradypodidae.
Wilson Viotto‐Souza, André Luiz Quagliatto Santos, Marcelo Abidu‐Figueiredo, Thaís Aparecida Silva, Rodrigo Ananias Barreiros Silva, Paulo de Souza‐Junior   +5 more
wiley   +1 more source

Skeletal pathologies in extant crocodilians as a window into the paleopathology of fossil archosaurs

The Anatomical Record, EarlyView.
Abstract Crocodilians, together with birds, are the only extant relatives to many extinct archosaur groups, making them highly important for interpreting paleopathological conditions in a phylogenetic disease bracketing model. Despite this, comprehensive data on osteopathologies in crocodilians remain scarce.
Alexis Cornille, Kyla Beguesse, Ewan Wolff, Clemens Zinner, Patrick Asbach, François Clarac, Florian Witzmann   +6 more
wiley   +1 more source

New craniodental materials of Falcarius utahensis (Theropoda: Therizinosauria) reveal patterns of intraspecific variation and cranial evolution in early coelurosaurians

The Anatomical Record, EarlyView.
Abstract Despite documented ecomorphological shifts toward an herbivorous diet in several coelurosaurian lineages, the evolutionary tempo and mode of these changes remain poorly understood, hampered by sparse cranial materials for early representatives of major clades. This is particularly true for Therizinosauria, with representative crania best known
William J. Freimuth, Lindsay E. Zanno
wiley   +1 more source

The coelurosaur theropods of the Romualdo formation, early Cretaceous (Aptian) of Brazil: Santanaraptor placidus meets Mirischia asymmetrica

The Anatomical Record, EarlyView.
Abstract The upper carbonate concretion levels of the Romualdo Formation (Aptian, Brazil) have yielded several theropod dinosaur remains, including spinosaurids and the coelurosaurs Santanaraptor placidus and Mirischia asymmetrica, the phylogenetic affinities of which are controversial.
Rafael Delcourt, Orlando Nelson Grillo, Christophe Hendrickx, Maximilian Kellermann, Max Cardoso Langer   +4 more
wiley   +1 more source

Morphological variation in atlas and axis of Neotropical spiny rats (Rodentia, Echimyidae)

The Anatomical Record, EarlyView.
Abstract The unique morphologies of the first two cervical vertebrae, the atlas and axis, represent a significant innovation in mammalian evolution. These structures support the weight of the head and enable intricate movements of the head and neck.
Thomas Furtado da Silva Netto, João Felipe Leal Kaiuca, Adriana Itatí Olivares, William Corrêa Tavares   +3 more
wiley   +1 more source

Growth dynamics, skeletochronology, and histovariability of the theropod dinosaur Berthasaura leopoldinae

The Anatomical Record, EarlyView.
Osteohistological sampling on different bones of theropod dinosaur documents discrepant age record, growth, and metabolism. This could result unprecise paleobiological inferences if samplings are based on single bones. However, multi‐bone sampling can attenuate these discrepancies, helping to infer growth dynamics and physiology of these extinct ...
Geovane Alves de Souza, Marina Bento Soares, Luiz Carlos Weinschütz, Alexander Wilhelm Armin Kellner   +3 more
wiley   +1 more source

Osteohistology of two phorusrhacids reveals uninterrupted growth strategy

The Anatomical Record, EarlyView.
Abstract Phorusrhacidae were apex predators that primarily dominated South America ecosystems for at least 40 million years with their imposing size and predatory lifestyle—yet some aspects of their biology remain poorly understood. Osteohistology is a tool for understanding growth dynamics and biomechanical adaptations.
Lotta Dreyer, Christian Cooper, Jingmai O'Connor   +2 more
wiley   +1 more source

Differences in predominant collagen fiber orientation between dorsal and plantar trabecular bone tracts of adult mule deer calcanei suggest strain‐mode‐specific adaptation

The Anatomical Record, EarlyView.
Polarized microscopic images of the outer bone cortex (a and b) and deeper trabecular bone (c and d) of the deer calcaneus in thin cross‐sections. The brighter gray levels reflect more oblique‐to‐transverse collagen fibers in the compression/dorsal bone (a, c) and the darker gray levels reflect more longitudinal collagen in the tension/plantar bone (b,
John G. Skedros, John T. Cronin, Chad S. Mears, Brett W. Richards   +3 more
wiley   +1 more source

A second species of non‐crocodyliform crocodylomorph from the Late Triassic fissure deposits of southwestern UK: Implications for locomotory ecological diversity in Saltoposuchidae

The Anatomical Record, EarlyView.
Abstract The Late Triassic–Early Jurassic fissures of the Bristol Channel area (southwest England and south Wales) are renowned for their diverse vertebrate faunas. These assemblages have yielded an array of predominantly small‐bodied forms that are crucial to our understanding of the early evolution of several major tetrapod clades.
Ewan H. Bodenham, Stephan N. F. Spiekman, Susannah C. R. Maidment, Paul Upchurch, Philip D. Mannion   +4 more
wiley   +1 more source