Results 111 to 120 of about 255,828 (280)

Ontogenetic changes and sexual dimorphism in the cranium and mandible of the Atlantic walrus (Odobenus rosmarus rosmarus L.)

The Anatomical Record, EarlyView.
Abstract Walruses have been an important subsistence and cultural resource for humans and have been exploited for millennia across their distribution. This exploitation has contributed to severe declines in several populations and local extirpations.
Katrien Dierickx, Oliver Kersten, Youri van den Hurk, Brenna A. Frasier, Richard Sabin, Bastiaan Star, James H. Barrett   +6 more
wiley   +1 more source

Barremian planktonic foraminiferal events correlated with the ammonite zones from the San Lucas Formation, Michoacán (SW Mexico)

Revista Mexicana de Ciencias Geológicas, 2018
We studied the Tiringueo section from the San Lucas Formation, located in the state of Michoacán, SW Mexico. The section is a flysch sequence consisting of a rhythmic deposit of shale, siltstone, and fine to medium graded sandstone interbedded with ...
Lourdes Omaña, Celestina González-Arreola, Blanca Margarita Ramírez-Garza   +2 more
doaj  

Revisiting a long‐overlooked skull: Implications for the distribution of Dinodontosaurus brevirostris (Kannemeyeriiformes) in the Brazilian Triassic

The Anatomical Record, EarlyView.
Abstract Dicynodonts (Anomodontia: Dicynodontia) were one of the main groups of terrestrial tetrapods in Permian and Triassic faunas. In Brazil, the genus Dinodontosaurus is one of the most common tetrapod taxon in the Triassic Santa Maria Supersequence. This genus has a complex taxonomic history and is represented in the Triassic of both Argentina and
Julia Lara Rodrigues de Souza, João Lucas Da Silva, Voltaire D. P. Neto, Arielli Fabrício Machado, Juan A. Escobar, Felipe L. Pinheiro   +5 more
wiley   +1 more source

Values of Lucas Sequences Modulo Primes

Rocky Mountain Journal of Mathematics, 2003
Let \(F_n\) denote the Fibonacci numbers. It is very easy to show that primes \(p \neq 5\) divide \(F_{p \pm 1}\), but finding the correct sign involves a piece of quadratic reciprocity. \textit{M. Ward} [Pac. J. Math. 11, 379--386 (1961; Zbl 0112.26904)] has observed that the question which primes divide \(F_{(p \pm 1)/k}\) for \(k = 2, 3, 4 \ldots ...
openaire   +3 more sources

A detailed redescription of a skeletally immature ‘Redondasaurus’ suggests ontogenetic transformations in the taxon mirror phytosaurian morphological evolution

The Anatomical Record, EarlyView.
Abstract The study of morphological evolution is fundamentally tied to ontogeny, yet studies of these heterochronic processes in the fossil record are rare. Fossils belonging to an ontogenetic series are difficult to assign to an ontogenetic stage due to inconsistent proxies for skeletal ages, challenging to taxonomically assign due to morphological ...
Erika R. Goldsmith, Michelle R. Stocker
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

On the Domain of the Pell-Lucas Matrix in the Spaces c and c_0

Dera Natung Government College Research Journal
In this study, we introduce new Banach sequence spaces $c(\Theta), c_0(\Theta)$, defined via a regular infinite matrix $ \Theta = (\lambda_{nk})$, where \[ \Theta_{nk} = \begin{cases} \dfrac{2\lambda_k}{3\lambda_n+\lambda_{n-1}} & 0 \leq k \leq n ...
Shiva Shah
doaj   +1 more source

An ontological morphological phylogenetic framework for living and extinct ray‐finned fishes (Actinopterygii)

The Anatomical Record, EarlyView.
Abstract The ray‐finned fishes include one out of every two species of living vertebrates on Earth and have an abundant fossil record stretching 380 million years into the past. The division of systematic knowledge of ray‐finned fishes between paleontologists working on extinct animals and neontologists studying extant species has obscured the ...
Jack Stack
wiley   +1 more source

An unusual titanosaur axis from the Upper Cretaceous of Brazil and its significance for sauropod anatomy and systematics

The Anatomical Record, EarlyView.
Abstract The Upper Cretaceous São José do Rio Preto Formation (Bauru Group, southeastern Brazil) has yielded a fragmentary but taxonomically diverse record of titanosaur sauropods, although elements from cervical series remain scarce. Here, we describe a nearly complete sauropod axis from the Vila Ventura Paleontological Area, representing an uncommon ...
Bruno A. Navarro, Jeffrey A. Wilson Mantilla, Jhonata H. A. Martins, Fabiano V. Iori, Leonardo S. Paschoa, Alberto B. Carvalho, Joseli M. Piranha, Hussam Zaher   +7 more
wiley   +1 more source

The petrotympanic canal (Huguier canal): Evolutionary, anatomical, and medical perspectives

The Anatomical Record, EarlyView.
Abstract The petrotympanic canal, traditionally referred to as Civinini's or Huguier's canal, represents an anatomical passage connecting the middle ear and temporomandibular joint (TMJ). Despite its early description, its structural complexity and functional significance have often been underestimated. In this study, we combined historical, anatomical,
Andrea Papini, Nicola Montemurro, Ferdinando Paternostro, Immacolata Belviso, Massimo Galli, Petra Martini, Licia Uccelli, Jacopo Moggi‐Cecchi, Gregorio Oxilia   +8 more
wiley   +1 more source