Results 221 to 230 of about 2,840,879 (289)

Comparative cranial biomechanics reveal macroevolutionary trends in theropod dinosaurs, with emphasis on Tyrannosauroidea

The Anatomical Record, EarlyView.
Abstract Tyrannosaurus is viewed as a model organism in vertebrate paleontology, with numerous studies analyzing its feeding biomechanics. Nonetheless, the evolution of this feeding performance has been under‐addressed in Tyrannosauroidea, especially in basal tyrannosauroids. Here we used muscle‐force reconstruction and finite element analysis (FEA) to
Evan Johnson‐Ransom, Paul Gignac, Daniel E. Barta, Ryan N. Felice, Eric Snively   +4 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

Inter‐ and intraspecific variation in theropod dinosaur dental microwear and its palaeoecological implications

The Anatomical Record, EarlyView.
Abstract Differences in skull and tooth morphology, stomach contents, and estimated bite force between medium‐to‐large sized (≥100 kg) predatory theropod dinosaurs have long been suspected to correlate with differences in their diets and dietary guilds (e.g., hypercarnivory, piscivory).
Cassius Morrison, James Gregory, Christopher Jackson, Jordan Bestwick, Katlin Schroeder, Samuel J.L. Gascoigne, Paul Bills, Laura B. Porro, Philip D. Mannion, Paul M. Barrett   +9 more
wiley   +1 more source

MicroCT reinvestigation of the only articulated fossil anostomid fish reveals synonymy of Arhinolemur Ameghino, 1898 and Megaleporinus Ramirez et al., 2017

The Anatomical Record, EarlyView.
Abstract Arhinolemur scalabrinii† Ameghino, 1898 was originally described as a strepsirrhine primate (Mammalia) but has been recognized as an anostomid fish since 2012. It remains the only extinct anostomid species known from complete cranial material.
Karen M. Panzeri, Humberto L. Andrelino, Sergio Bogan, José P. O'Gorman, Federico Agnolín, Brian L. Sidlauskas, Nahuel Vega, Agustín G. Martinelli, José L. Birindelli   +8 more
wiley   +1 more source

Early evolution of the gular musculature and its innervation in ray‐finned fishes

The Anatomical Record, EarlyView.
Abstract Gular muscles are an important but often overlooked component of cranial anatomy in bony fishes. They are located on the ventral surface of the head and are derived from the mandibular and hyoid arches. We present a comprehensive review of the gular musculature and its innervation across early diverging actinopterygian lineages. By integrating
Aléssio Datovo, Paulo Presti, George Vita, Murilo N. L. Pastana, Luiz A. W. Peixoto   +4 more
wiley   +1 more source

Clade‐wide morphological and functional variation of the sauropsid columella

The Anatomical Record, EarlyView.
Abstract The columella (=stapes) is the middle ear bone of reptiles that transmits vibrations from the environment to the inner ear. It has been shown to exhibit extensive interspecific morphological disparity in several clades; however, its morphological variation and associated functional consequences remain poorly described.
John Peacock, Serjoscha W. Evers, Tiago R. Simões, Garth M. Spellman, Daniel J. Field   +4 more
wiley   +1 more source

Drivers of tail evolution in squamates and their implications for the fossorial origin of snakes

The Anatomical Record, EarlyView.
Abstract The axial skeleton serves as the primary structural support in all vertebrates and is subdivided into five distinct regions: cervical, thoracic, lumbar, sacral, and caudal. Relaxation of constraints acting on the terminal end of the axial skeleton has led to remarkable variation in caudal vertebrae number across Squamata.
Olivia Binfield, Marco Camaiti, Lucy Roberts   +2 more
wiley   +1 more source

Exploring the cranial morphology and possible convergences of Triassic non‐crocodylomorph pseudosuchians (Archosauria: Pseudosuchia) with other sauropsids through linear morphometrics

The Anatomical Record, EarlyView.
Abstract Triassic pseudosuchians had highly diversified cranial morphologies. These archosaurs occupied diverse ecological roles, ranging from terrestrial predators and herbivores to semiaquatic ambush predators and possible waders. Here, we apply linear cranial morphometrics to assess possible convergences with other sauropsids from the clades ...
Rafael Terras, Rodrigo Temp Müller, Leonardo Kerber, Mirian Carbonera   +3 more
wiley   +1 more source

Dental anomalies in Pleistocene African hippopotamuses from Olduvai Bed II

The Anatomical Record, EarlyView.
Abstract Hippopotamuses are key palaeoenvironmental indicators in African Pleistocene ecosystems due to their ecological dependence on permanent water bodies and their frequent representation in the fossil record. This study examines dental anomalies in Hippopotamus cf. gorgops from several localities in Bed II of Olduvai Gorge (Tanzania), dated to ca.
Darío Fidalgo, Faysal Bibi, Jean‐Renaud Boisserie, Jackson K. Njau, Ignacio de la Torre   +4 more
wiley   +1 more source

Male reproductive system in stenopodidean shrimps: Unveiling basal reproductive traits in shrimp‐like Pleocyemata (Stenopodidae and Spongicolidae)

The Anatomical Record, EarlyView.
Abstract Stenopodidea represents one of the basal lineages within Pleocyemata, yet the male reproductive system (MRS) of this group remains poorly understood, with limited information available regarding its morphology and function. This study provides the first detailed description of the MRS in four stenopodidean shrimp species from two families ...
Caio Santos Nogueira, Lucas Rezende Penido Paschoal, Fernando José Zara   +2 more
wiley   +1 more source