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1.
J Anat ; 244(4): 557-593, 2024 04.
Artículo en Inglés | MEDLINE | ID: mdl-38037880

RESUMEN

Piatnitzkysauridae were Jurassic theropods that represented the earliest diverging branch of Megalosauroidea, being one of the earliest lineages to have evolved moderate body size. This clade's typical body size and some unusual anatomical features raise questions about locomotor function and specializations to aid in body support; and other palaeobiological issues. Biomechanical models and simulations can illuminate how extinct animals may have moved, but require anatomical data as inputs. With a phylogenetic context, osteological evidence, and neontological data on anatomy, it is possible to infer the musculature of extinct taxa. Here, we reconstructed the hindlimb musculature of Piatnitzkysauridae (Condorraptor, Marshosaurus, and Piatnitzkysaurus). We chose this clade for future usage in biomechanics, for comparisons with myological reconstructions of other theropods, and for the resulting evolutionary implications of our reconstructions; differential preservation affects these inferences, so we discuss these issues as well. We considered 32 muscles in total: for Piatnitzkysaurus, the attachments of 29 muscles could be inferred based on the osteological correlates; meanwhile, in Condorraptor and Marshosaurus, we respectively inferred 21 and 12 muscles. We found great anatomical similarity within Piatnitzkysauridae, but differences such as the origin of M. ambiens and size of M. caudofemoralis brevis are present. Similarities were evident with Aves, such as the division of the M. iliofemoralis externus and M. iliotrochantericus caudalis and a broad depression for the M. gastrocnemius pars medialis origin on the cnemial crest. Nevertheless, we infer plesiomorphic features such as the origins of M. puboischiofemoralis internus 1 around the "cuppedicus" fossa and M. ischiotrochantericus medially on the ischium. As the first attempt to reconstruct muscles in early tetanurans, our study allows a more complete understanding of myological evolution in theropod pelvic appendages.


Asunto(s)
Evolución Biológica , Dinosaurios , Animales , Filogenia , Extremidad Inferior , Miembro Posterior/anatomía & histología , Dinosaurios/anatomía & histología , Músculo Esquelético/anatomía & histología
2.
An Acad Bras Cienc ; 93(suppl 2): e20201642, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-34378649

RESUMEN

The Solimões and Acre basins are complex geological units related to the Andean uplift, covering the Northwestern region of Brazil, being one of the most important units due to their fossil diversity. In order to produce a document that integrates part of the fossil records of this region, we compiled/georeferenced localities from literature on which tetrapods are described, focusing on Solimões Formation but not restricted to this unit. We were able to recognize 208 localities, documented in over two centuries of reports of fossils from several taxonomic groups from the proto-Amazonia, 199 new entries in Paleobiology Database. We summarize, for each locality, its geographical position, geological information, age, and data of the paleodiversity. Most outcrops in the Amazonia region are located on river banks (~96%), while road cuts and other non-riverside outcrops represent the remainder (~4%). Most tetrapod are Mammalia, followed by Testudinata, and Crocodyliformes. This work reinforces the need for a more controlled and refined prospecting at the Solimões/Acre Basins, especially in the Solimões Formation, which represents the majority of fossiliferous records, to help answer old questions, such as dating, and new ones, here discussed, such as the paleodiversity patterns and temporal distribution among the mapped localities.


Asunto(s)
Fósiles , Mapeo Geográfico , Animales , Brasil , Reptiles , Ríos
3.
Public Health Nutr ; 16(8): 1403-13, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22916703

RESUMEN

OBJECTIVE: To evaluate the effect of fibre intake on the evolution of maternal BMI from pregnancy to postpartum and to identify dietary patterns associated with fibre intake. DESIGN: Cohort study. Food intake was obtained using an FFQ. Focused principal component analysis was used focusing on the variables: postpartum weight retention and total dietary fibre intake. Poisson regression models with robust variance were built in order to measure the effect of fibre intake during the postpartum period on obesity risk. SETTING: Primary care clinics in southern Brazil. SUBJECTS: Pregnant women (n 370) were followed until the 5th month postpartum. RESULTS: The highest contribution to fibre intake came from the consumption of beans. Consumption of bread and rice indicated a common Brazilian food pattern along with beans. Participants retained a median of 4.4 (interquartile range 0.6, 7.9) kg of weight gained during pregnancy. Obesity risk, defined as an unfavourable evolution of BMI during pregnancy and postpartum, was present in 189 (55.1%) women. Individual food items did not have an important effect on weight retention. In Poisson regression adjusting for maternal age, pre-pregnancy BMI and total gestational weight gain, inadequate postpartum fibre intake increased obesity risk by 24% (relative risk 51.24; 95% CI 1.05, 1.47). CONCLUSIONS: Important maternal weight retention occurred in these women. Adequate fibre intake may reduce obesity risk in the period following childbirth.


Asunto(s)
Índice de Masa Corporal , Fibras de la Dieta/administración & dosificación , Ingestión de Energía , Periodo Posparto , Embarazo , Adulto , Peso Corporal , Brasil , Estudios de Cohortes , Femenino , Humanos , Política Nutricional , Obesidad/prevención & control , Distribución de Poisson , Factores de Riesgo , Factores Socioeconómicos , Encuestas y Cuestionarios , Salud de la Mujer , Adulto Joven
4.
R Soc Open Sci ; 10(8): 230481, 2023 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-37593714

RESUMEN

During the Mesozoic, non-avian theropods represented one of the most successful clades globally distributed, with a wide diversity of forms. An example is the clade Megalosauroidea, which included medium- to large-bodied forms. Here, we analyse the macroevolution of the locomotor system in early Theropoda, emphasizing the Megalosauroidea. We scored the Spinosaurus neotype in a published taxon-character matrix and described the associated modifications in character states, mapping them onto a phylogeny and using these to study disparity. In the evolution of Megalosauroidea, there was the mosaic emergence of a low swollen ridge; enlargement of the posterior brevis fossa and emergence of a posterodorsal process on the ilium in some megalosauroids; emergence of a femoral head oriented anteromedially and medially angled, and appearance of posterolaterally oriented medial femoral condyles in spinosaurids. The greatest morphological disparity is in the ilium of megalosaurids; the ischium seems to have a high degree of homoplasy; there is a clear distinction in the femoral morphospace regarding megalosauroids and other theropods; piatnitzkysaurids show considerable disparity of zeugopodial characters. These reconstructions of osteological evolution form a stronger basis on which other studies could build, such as mapping of pelvic/appendicular musculature and/or correlating skeletal traits with changes in locomotor function.

5.
Zootaxa ; 5264(4): 526-544, 2023 Apr 17.
Artículo en Inglés | MEDLINE | ID: mdl-37518033

RESUMEN

We report the first occurrence in South America of spinosaurid specimens belonging to the clade Baryonychinae. The material comprises three tooth crowns recovered from the Lower Cretaceous (Berriasian-Valanginian) of the Feliz Deserto Formation, State of Sergipe, northeast Brazil. The three specimens have the typical conidont condition, displaying a fluted morphology, veined enamel texture and carinae extending to the cervix region, conditions similar to those shared among spinosaurid theropods. Furthermore, a notable feature is the presence of a serrated carinae composed of 6-7 diminutive denticles per millimetre, a key feature shared by baryonychine spinosaurids. Phylogenetic and multivariate analyses performed on dentition-based and crown-based datasets of theropod taxa confirm the relationship of the three tooth crowns described here with the well-supported spinosaurid clade. Our results retrieve the taxa which comprise the "classically" baryonychine clade as individual branches within a polytomy which includes the three tooth crowns and a subclade of spinosaurines (Spinosaurus + Angaturama/Irritator). Additionally, the discriminant and cluster analyses suggest that the materials are more similar to Suchomimus than to Baryonyx morphometrically, but clearly bearing similarities with baryonychines (sharing a similar morphospace). These new findings paleogeographically expand the occurrence of this clade to western Gondwana, and comprise one of the oldest spinosaurid records worldwide, which brings implications on hypotheses for the emergence and evolution of the clade. Furthermore, these new records indicate the presence of more than one spinosaurid taxon in the Lower Cretaceous deltaic paleoenvironment of the Feliz Deserto Formation.


Asunto(s)
Dinosaurios , Fósiles , Corona del Diente , Animales , Dinosaurios/anatomía & histología , Dinosaurios/clasificación , Filogenia , Corona del Diente/anatomía & histología , Brasil
6.
Zootaxa ; 4894(4): zootaxa.4894.4.5, 2020 Dec 11.
Artículo en Inglés | MEDLINE | ID: mdl-33311064

RESUMEN

The Solimões Formation (Eocene-Pliocene) is a well-known geological unit due to the great diversity of crocodylian species. Here we describe a new species of Melanosuchus, M. latrubessei sp. nov., from the Talismã locality, state of Amazonas, from the Upper Miocene of the Solimões Formation (Solimões Basin, Brazil). A new phylogenetic inference focused on Caimaninae is provided and the different evolutionary scenarios involving this new species are discussed. In addition, quantitative morphology studies are carried out and comments regarding the paleoecology aspects of this new species are made. M. latrubessei represents a medium-sized generalist predator, being proportional to the medium-sized M. niger. This new species inhabited the drainages of the Solimões Formation and was ecologically related to other taxa of crocodylians during the proto-Amazon Miocene. The evolutionary advantages of Melanosuchus genus are discussed to better understand the biogeographical occurrence of M. niger in South America, a species which survives to this day in contrast to several other species that became extinct during the Miocene-Pliocene periods. The extinction of the Miocene-Pliocene crocodylian taxa of the Solimões Formation, including Melanosuchus latrubessei, seems to be directly related with the uplift of the northern portions of the Andes, which generated significantly changes in drainages and Amazon paleoenvironments.


Asunto(s)
Reptiles , Animales , Brasil , Filogenia
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