Results 71 to 80 of about 22,010 (171)

Occurrence of multiple congenital anomalies in Potamotrygon amandae (Elasmobranchii, Potamotrygoninae) embryos, including the first report of bicephaly

Journal of Fish Biology, EarlyView.
Abstract Reports of teratogenic embryos in elasmobranchs have been documented in multiple species, with proposed aetiologies including environmental disturbances, genetic mutations, predation, exposure to endocrine‐disrupting compounds and maternal stress.
Douglas de Castro Ribeiro, Raquel Lopes Queiroz, Cristiéle da Silva Ribeiro   +2 more
wiley   +1 more source

Gestión, evaluación de las necesidades de conservación y jerarquización de una colección mediante su inventario

Ge-conservación
Para la conservación de los materiales paleontológicos es imprescindible disponer de forma ordenada toda la información que afecta a cada ejemplar y basándonos en la experiencia adquirida en la conservación de la colección de vertebrados del yacimiento ...
Fátima Marcos Fernández, Santiago Martín de Jesús, Pedro Mocho, Adrián Páramo Blázquez, Marta Plaza Beltrán, Francisco Ortega   +5 more
doaj   +1 more source

First Record of an Extinct Marabou Stork in the Neogene of South America [PDF]

, 2008
We describe a new large species of marabou stork, Leptoptilus patagonicus(Ciconiiformes, Ciconiidae, Leptoptilini), from the late Miocene Puerto Madryn Formation, Chubut Province, Argentina.
Cladera, Gerardo, Noriega, Jorge Ignacio
core   +1 more source

Hindlimb functional morphology and locomotor biomechanics of the small Late Triassic pseudosuchian reptile Gracilisuchus stipanicicorum (Archosauria: Gracilisuchidae)

Journal of Anatomy, EarlyView.
A three‐dimensional biomechanical model of the musculoskeletal system is used to analyse the potential locomotor functions of the small (~1 kg) Late Triassic archosaurian reptile Gracilisuchus stipanicicorum. The study finds that, potentially like the ancestral archosaur, this taxon was probably quadrupedal, plantigrade and neither strongly sprawling ...
Agustina Lecuona, Emily Keeble, Yuting Lin, John R. Hutchinson   +3 more
wiley   +1 more source

Características diferenciales entre el fragmento de cráneo de Homo sp. de Venta Micena (Orce, Granada) y los equidos

Estudios Geologicos, 1989
Se ha realizado un detallado estudio diferencial entre la morfología del fragmento craneal de Orce y varios équidos jóvenes, puesto que en anteriores trabajos ya se ha separado del resto de los mamíferos.
G. Gibert, F. Ribot, C. Ferrández, B. Martínez, R. Caporicci   +4 more
doaj   +1 more source

Virtual brain endocasts of the palaeanodont Metacheiromys marshi and the neurosensory evolution of early Pholidotamorpha

Journal of Anatomy, EarlyView.
We describe the endocranial anatomy of Metacheiromys marshi. Decrease in olfaction and eye movement control occurred through time in Pholidotamorpha and is likely linked to fossorial adaptations. The development of the orbital gyrus might be related to the evolution of myrmecophagy and the emergence of a protrusile tongue in early Pholidotamorpha ...
Eduard Cabasés Bru, Raquel Moya‐Costa, John R. Wible, Stephen L. Brusatte, Ornella C. Bertrand   +4 more
wiley   +1 more source

Programas de Investigación en Paleobiología y Teoría evolutiva

Arbor: Ciencia, Pensamiento y Cultura, 2002
Se presenta una discusión del papel actual de la paleontología en el estudio de la evolución orgánica. Diferentes descubrimientos, tanto teóricos como empíricos, están cuestionando algunos de los principios básicos del paradigma neodarvinista.
Antonio Rosas González
doaj   +1 more source

Evolución geológica en la cuenca baja del río Colorado durante el cenozoico, Patagonia Norte, Argentina [PDF]

, 2019
Climatic changes and eustatic sea levels have been assumed to be the most important controllers of the Colorado River alluvial fan in northern Patagonia.
Perillo, Gerardo Miguel E., Seitz, Carina, Vélez, María I.   +2 more
core   +2 more sources

Microbially generated ferruginous crusts: A potential biosignature of continental input in coastal settings

Sedimentology, EarlyView.
ABSTRACT Thin ferruginous sandy crusts are common on top of sandstone beds in the Early Permian post‐glacial deposits of the Paraná Basin in southern Brazil. These crusts usually preserve wrinkle structures, suggesting that they might be a product of microbial mediation.
Patrícia Weschenfelder, Renata Guimarães Netto, Alisson Klayton Martins   +2 more
wiley   +1 more source

Development of Holocene lacustrine microbialites on the Iberian Peninsula: Insights into environmental and depositional controls using X‐ray CT and petrography

Sedimentology, EarlyView.
ABSTRACT Microbial mats and microbialites are common in modern and ancient saline lacustrine environments and are highly responsive to biological and environmental factors. As such, they represent important sources of high‐resolution environmental data across a wide range of geological time. Nonetheless, interpretation of fossil mats is non‐trivial due
Connor Doyle, Juan Pablo Corella, Julia Behnsen, Mario Morellón, Celia Martín‐Puertas, Blas Valero Garcés, Stefan Schröder   +6 more
wiley   +1 more source