Male genital system of Ameiva ameiva (Squamata: Teiidae)
We examined 10 transverse histological sections per individual and measured the epithelial height of the epididymis and ductus deferens. The male reproductive system consists of a pair of yellowish oval testes, the rete testis, ductuli efferentes, epididymis, ductus deferens, ampulla ductus deferentis, sexual segment of the kidney (SSK), cloaca, and hemipenis. The hemipenis is elongated, cylindrical, and unilobed, with a sulcate face and an asulcate face, which has continuous fringes throughout its length. Seminiferous tubules exhibited germ cells at various stages. The epididymis is wider and more coiled than the ductus d...
Source: Anatomical Record - April 26, 2024 Category: Anatomy Authors: Érica da Silva Maciel Rodrigo Zieri Selma Maria de Almeida-Santos Source Type: research
How smart was T. rex? Testing claims of exceptional cognition in dinosaurs and the application of neuron count estimates in palaeontological research
We present revised estimates of encephalization and telencephalic neuron counts in dinosaurs, which we derive from phylogenetically informed modeling and an amended dataset of endocranial measurements. For large-bodied theropods in particular, we recover significantly lower neuron counts than previously proposed. Furthermore, we review the suitability of neurological variables such as neuron numbers and relative brain size to predict cognitive complexity, metabolic rate and life history traits in dinosaurs, coming to the conclusion that they are flawed proxies for these biological phenomena. Instead of relying on such neur...
Source: Anatomical Record - April 26, 2024 Category: Anatomy Authors: Kai R Caspar Cristi án Gutiérrez-Ibáñez Ornella C Bertrand Thomas Carr Jennifer A D Colbourne Arthur Erb Hady George Thomas R Holtz Darren Naish Douglas R Wylie Grant R Hurlburt Source Type: research
Male genital system of Ameiva ameiva (Squamata: Teiidae)
We examined 10 transverse histological sections per individual and measured the epithelial height of the epididymis and ductus deferens. The male reproductive system consists of a pair of yellowish oval testes, the rete testis, ductuli efferentes, epididymis, ductus deferens, ampulla ductus deferentis, sexual segment of the kidney (SSK), cloaca, and hemipenis. The hemipenis is elongated, cylindrical, and unilobed, with a sulcate face and an asulcate face, which has continuous fringes throughout its length. Seminiferous tubules exhibited germ cells at various stages. The epididymis is wider and more coiled than the ductus d...
Source: Anatomical Record - April 26, 2024 Category: Anatomy Authors: Érica da Silva Maciel Rodrigo Zieri Selma Maria de Almeida-Santos Source Type: research
The scimitar-cat Homotherium from the submerged continental shelf of the Gulf Coast of Texas
We report on a new record of Homotherium based on a fragmentary premaxilla-maxilla discovered on McFaddin Beach, Texas, along the Gulf of Mexico. Skeletal remains of extinct, Pleistocene vertebrates accumulate on McFaddin Beach. Those fossils appear to originate from submerged deposits on the continental shelf in the Gulf of Mexico, an area that was subaerially exposed in the Late Pleistocene during glacial intervals. Marine erosion and transport altered the externally visible morphology of the current specimen, obscuring and/or damaging taxonomically informative details of the preserved dentition. However, high-resolution...
Source: Anatomical Record - April 24, 2024 Category: Anatomy Authors: John A Moretti Deanna Flores Christopher J Bell Will Godwin Adam Hartstone-Rose Patrick J Lewis Source Type: research
The pseudosuchian record in paleohistology: A small review
Anat Rec (Hoboken). 2024 Apr 24. doi: 10.1002/ar.25455. Online ahead of print.ABSTRACTArchosauria originated around the Earth's largest biotic crisis that severely affected all ecosystems globally, the Permotriassic Mass extinction event, and comprises two crown-group lineages: the bird-lineage and the crocodylian lineage. The bird lineage includes the iconic pterosaurs, as well as dinosaurs and birds, whereas the crocodylian lineage includes clades such as aetosaurs, poposaurs, "rauisuchians," as well as Crocodylomorpha; the latter being represented today only by less than 30 extant species of Crocodylia. Despite playing ...
Source: Anatomical Record - April 24, 2024 Category: Anatomy Authors: Torsten M Scheyer Source Type: research
The scimitar-cat Homotherium from the submerged continental shelf of the Gulf Coast of Texas
We report on a new record of Homotherium based on a fragmentary premaxilla-maxilla discovered on McFaddin Beach, Texas, along the Gulf of Mexico. Skeletal remains of extinct, Pleistocene vertebrates accumulate on McFaddin Beach. Those fossils appear to originate from submerged deposits on the continental shelf in the Gulf of Mexico, an area that was subaerially exposed in the Late Pleistocene during glacial intervals. Marine erosion and transport altered the externally visible morphology of the current specimen, obscuring and/or damaging taxonomically informative details of the preserved dentition. However, high-resolution...
Source: Anatomical Record - April 24, 2024 Category: Anatomy Authors: John A Moretti Deanna Flores Christopher J Bell Will Godwin Adam Hartstone-Rose Patrick J Lewis Source Type: research
The pseudosuchian record in paleohistology: A small review
Anat Rec (Hoboken). 2024 Apr 24. doi: 10.1002/ar.25455. Online ahead of print.ABSTRACTArchosauria originated around the Earth's largest biotic crisis that severely affected all ecosystems globally, the Permotriassic Mass extinction event, and comprises two crown-group lineages: the bird-lineage and the crocodylian lineage. The bird lineage includes the iconic pterosaurs, as well as dinosaurs and birds, whereas the crocodylian lineage includes clades such as aetosaurs, poposaurs, "rauisuchians," as well as Crocodylomorpha; the latter being represented today only by less than 30 extant species of Crocodylia. Despite playing ...
Source: Anatomical Record - April 24, 2024 Category: Anatomy Authors: Torsten M Scheyer Source Type: research
Morphological diversity of saber-tooth upper canines and its functional implications
Anat Rec (Hoboken). 2024 Apr 22. doi: 10.1002/ar.25458. Online ahead of print.ABSTRACTElongated upper canine teeth, commonly known as saber-teeth, have evolved three times within the sub-order Feliformia. The species that wielded them flourished throughout the Cenozoic and have historically been separated into two morphological groups: the dirk-tooths with longer, flatter canines, and the scimitar-tooths with shorter, serrated teeth. However, quantitative morphological analysis has not been conducted on these teeth to determine the true amount of diversity within the group, and how the upper canine morphology of extant fel...
Source: Anatomical Record - April 22, 2024 Category: Anatomy Authors: Caitlin D Shelbourne Stephan Lautenschlager Source Type: research
Evaluating extinct pseudosuchian body mass estimates using a femur volume-based model
Anat Rec (Hoboken). 2024 Apr 18. doi: 10.1002/ar.25452. Online ahead of print.ABSTRACTThe clade Pseudosuchia appeared 250 million years ago. The exclusively semi-aquatic Crocodylia, which includes crocodiles, alligators, caimans, and gharials is the only surviving subgroup. Investigating Crocodylia biology is pivotal for inferring traits of extinct pseudosuchians. Alligator femur length is widely used for modeling pseudosuchian body mass, but the regression is influenced by sex and captivity status, leading to potential accuracy problems. An alternative model results from the correlation between alligator femur volume and ...
Source: Anatomical Record - April 18, 2024 Category: Anatomy Authors: Holly N Woodward Paul Aubier Mariana Val éria Araújo de Sena Jorge Cubo Source Type: research
Evaluating extinct pseudosuchian body mass estimates using a femur volume-based model
Anat Rec (Hoboken). 2024 Apr 18. doi: 10.1002/ar.25452. Online ahead of print.ABSTRACTThe clade Pseudosuchia appeared 250 million years ago. The exclusively semi-aquatic Crocodylia, which includes crocodiles, alligators, caimans, and gharials is the only surviving subgroup. Investigating Crocodylia biology is pivotal for inferring traits of extinct pseudosuchians. Alligator femur length is widely used for modeling pseudosuchian body mass, but the regression is influenced by sex and captivity status, leading to potential accuracy problems. An alternative model results from the correlation between alligator femur volume and ...
Source: Anatomical Record - April 18, 2024 Category: Anatomy Authors: Holly N Woodward Paul Aubier Mariana Val éria Araújo de Sena Jorge Cubo Source Type: research
Angiogenic and anti-angiogenic factors during the post-hatching growth of the quail (Coturnix coturnix japonica) spleen
Anat Rec (Hoboken). 2024 Apr 16. doi: 10.1002/ar.25454. Online ahead of print.ABSTRACTVascular endothelial growth factor (VEGF) family members are responsible for endothelial cells' growth, proliferation, migration, angiogenesis, vascular permeability, and differentiation and proliferation of non-endothelial cell types. VEGF and its receptors are found in mammalian lymphoid organs. The present study was conceived to determine (a) the presence and localization of angiogenic VEGF and its receptors (Fms-like tyrosine kinase 1 [Flt1/fms], fetal liver kinase 1 [Flk1]/kinase insert domain receptor [KDR], Fms-like tyrosine kinase...
Source: Anatomical Record - April 16, 2024 Category: Anatomy Authors: Bayram Bayram Narin Liman Emel Alan Hakan Sa ğsöz Source Type: research
Angiogenic and anti-angiogenic factors during the post-hatching growth of the quail (Coturnix coturnix japonica) spleen
Anat Rec (Hoboken). 2024 Apr 16. doi: 10.1002/ar.25454. Online ahead of print.ABSTRACTVascular endothelial growth factor (VEGF) family members are responsible for endothelial cells' growth, proliferation, migration, angiogenesis, vascular permeability, and differentiation and proliferation of non-endothelial cell types. VEGF and its receptors are found in mammalian lymphoid organs. The present study was conceived to determine (a) the presence and localization of angiogenic VEGF and its receptors (Fms-like tyrosine kinase 1 [Flt1/fms], fetal liver kinase 1 [Flk1]/kinase insert domain receptor [KDR], Fms-like tyrosine kinase...
Source: Anatomical Record - April 16, 2024 Category: Anatomy Authors: Bayram Bayram Narin Liman Emel Alan Hakan Sa ğsöz Source Type: research
The vascular footprint in cardiac homeostasis and hypertensive heart disease-A link between apelin receptor, vascular endothelial growth factor, and neuronal nitric oxide synthase
Anat Rec (Hoboken). 2024 Apr 15. doi: 10.1002/ar.25453. Online ahead of print.ABSTRACTRecent studies have suggested a connection between disturbances of the apelin system and various cardiac pathologies, including hypertension, heart failure, and atherosclerosis. Vascular endothelial growth factor is crucial for cardiac homeostasis as a critical molecule in cardiac angiogenesis. Neuronal nitric oxide synthase is an essential enzyme producing nitric oxide, a key regulator of vascular tone. The present study aims to shed light upon the complex interactions between these three vital signaling molecules and examine their chang...
Source: Anatomical Record - April 15, 2024 Category: Anatomy Authors: Alexandar Iliev Lyubomir Gaydarski Georgi Kotov Boycho Landzhov Vidin Kirkov Stancho Stanchev Source Type: research
Comparative anatomy and evolution of the atlantoaxial complex in the fossorial lineage Amphisbaenia (Squamata: Lacertoidea)
In this study, we used computed microtomography data to describe in detail of the atlantoaxial complex for 15 species, belonging to all six current families of Amphisbaenia. Furthermore, we evaluate evolutionary scenarios of selected characters related to the atlantoaxial complex in the most recent phylogeny for Amphisbaenia, using the criteria of parsimony and maximum likelihood. Our results indicate that the evolutionary pattern of the atlantoaxial complex presents a diversification in its morphology that is not always correlated with the shape of the head. This analysis reinforces the hypothesis of remarkable morphologi...
Source: Anatomical Record - April 15, 2024 Category: Anatomy Authors: Clara Ara újo Salvino Cristian Hernand éz-Morales Juan Diego Daza Pedro M Sales Nunes Source Type: research
The vascular footprint in cardiac homeostasis and hypertensive heart disease-A link between apelin receptor, vascular endothelial growth factor, and neuronal nitric oxide synthase
Anat Rec (Hoboken). 2024 Apr 15. doi: 10.1002/ar.25453. Online ahead of print.ABSTRACTRecent studies have suggested a connection between disturbances of the apelin system and various cardiac pathologies, including hypertension, heart failure, and atherosclerosis. Vascular endothelial growth factor is crucial for cardiac homeostasis as a critical molecule in cardiac angiogenesis. Neuronal nitric oxide synthase is an essential enzyme producing nitric oxide, a key regulator of vascular tone. The present study aims to shed light upon the complex interactions between these three vital signaling molecules and examine their chang...
Source: Anatomical Record - April 15, 2024 Category: Anatomy Authors: Alexandar Iliev Lyubomir Gaydarski Georgi Kotov Boycho Landzhov Vidin Kirkov Stancho Stanchev Source Type: research
