Mostrando entradas con la etiqueta Jurásico Superior. Mostrar todas las entradas
Mostrando entradas con la etiqueta Jurásico Superior. Mostrar todas las entradas
8.7.26 , , , 0 comentarios

Estudo sobre um saurópode gigante da Junqueira (Pombal) no XII Congresso Nacional de Geologia


Uma equipe internacional paleontólogos do Instituto Dom Luiz da Faculdade de Ciências da Universidade de Lisboa, do Grupo de Biología Evolutiva da UNED, do Museu Nacional de História Natural e da Ciência, da Universidad Complutense de Madrid, entre outras instituições, apresentam no XII Congresso Nacional de Geologia, realizado no final de junho, em Évora, as mais recentes descobertas sobre os fósseis do Jurássico Superior de Pombal.


O paleontologo Pedro Mocho liderou um estudo sobre um dinossáurio saurópode de grande tamanho coletado na jazida da Junqueira em Santiago de Litém (Pombal). No trabalho intitulado “Sauropod presacral vertebrae from the Upper Jurassic deposits of Junqueira (Pombal, Portugal)”, Pedro Mocho e colaboradores descrevem, comparam e analisam vários restos fósseis encontrados nesta localidade, em particular, um conjunto des restos de vértebras dorsais. Neste estudo confirma-se a sua atribuição ao grupo dos braquiossaurídeos, e comparam de forma detalhada com outros membros des grupos, como Lusotitan atalaiensis, Giraffatitan brancai, Vouvria dampariensis e Brachiosaurus altithorax. O indivíduo da Junqueira correspondende a um dos maiores exemplares deste grupo encontrados na Europa. O resumo desta apresentação encontra-se abaixo:

The Iberian Peninsula has a relatively rich dinosaur record, especially in the Kimmeridgian–Tithonian deposits of the Lusitanian Basin, where sauropods with brachiosaurid affinities occur. However, European Upper Jurassic brachiosaurids remain poorly known due to scarce diagnostic fossils. To date, only four taxa have been formally recognized. Notably, the Upper Jurassic deposits of the Pombal region have proven especially productive, yielding several large-bodied individuals preliminarily assigned to Titanosauriformes. These include specimens from the Junqueira, Monte Agudo, and Mouriscas fossil sites. At Junqueira, a large sauropod was recovered from the Upper Jurassic deposits of the Bombarral Formation. The site excavated in 2015 during two paleontological expeditions yielded multiple axial and appendicular elements, including dorsal and caudal vertebrae, ribs, and portions of the pelvic girdle. Herein, we describe the presacral vertebrae of Junqueira sauropod. Dorsal vertebrae in sauropods provide key anatomical information for detailed systematic assessments, due to their structural complexity. The Junqueira specimens represent a single individual, being assigned to Titanosauriformes based on the presence of camellate internal bone and posterior acute pneumatic foramen. They also display a combination of features supporting their attribution to Brachiosauridae, including a divided spinopostzygapophyseal lamina (SPOL) in the middle and posterior dorsal vertebrae, strongly dorsoventrally compressed dorsal centra, and slightly opisthocoelous posterior dorsal centra. Additional diagnostic traits include well- developed hypantrum facets (ventrally connected by a thin lamina on both sides, like Giraffatitan brancai), prominent centroprezygapophyseal facets, and a ventrally displaced contact between the spinodiapophyseal lamina (SPDL) and SPOL that does not reach the triangular aliform process. This specimen provides valuable insights into the morphology of the Late Jurassic brachiosaurids from Portugal, exhibiting characteristics consistent with Lusotitan atalaiensis,  taxon otherwise known from considerably more fragmentary dorsal material.

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Estudo de um esfenodonte de Andrés (Pombal) no XII Congresso Nacional de Geologia


Uma equipe internacional paleontólogos do Grupo de Biología Evolutiva da UNED, do Museu Nacional de História Natural e da Ciência, da Fundación de Historia Natural Félix de Azara (Universidad Maimónides), do CONICET e da Faculdade de Ciências da Universidade de Lisboa, apresentam no XII Congresso Nacional de Geologia, realizado no final de junho, em Évora, algumas mais recentes descobertas sobre os fósseis do Jurássico Superior de Pombal.


As jazidas fossilíferas de Andrés e Junqueira em Pombal, com cerca de 150 milhões de anos, têm revelado uma extraordinária diversidade de fósseis de dinossáurios e outros vertebrados, reforçando a importância de Pombal como uma das principais regiões portuguesas para o estudo do Jurássico Superior. Entre os resultados apresentados destaca-se o estudo de um pequeno réptil esfenodonte (grupo atualmente representado pela Tuatara) encontrado na jazida de Andrés (Santiago de Litém, Pombal). Neste trabalho intitulado “A new Opisthodontian sphenodontian from Pombal (Portugal) and its implications for Late Jurassic lepidosaur evolution”, e apresentado pelo paleontólogo Francisco Ortega, o excelente estado de conservação do fóssil permitiu melhorar o nosso conhecimento sobre a evolução destes animais no continente europeu durante Jurássico Superior. O resumo desta apresentação encontra-se abaixo:

Sphenodontians are relics today of a once diverse and globally distributed component of Mesozoic terrestrial ecosystems. Yet, their Upper Jurassic European record remains scarce and fragmentary outside classic localities such as Solnhofen (Germany) and Cerin (France). Here we report a new sphenodontian from the Tithonian of the Lusitanian Basin (Andrés site, Pombal, Portugal), representing one of the most complete specimens of a fully terrestrial sphenodontian from the European Upper Jurassic. The material reported in preliminary studies includes a partial skeleton preserving a complete skull and articulated postcrania. The specimen comes from fluvial to floodplain deposits of the Bombarral Fm., indicating a fully terrestrial environment linked to a low-energy meandering river system. Comparative anatomical analysis supports its assignment to Opisthodontia, showing close affinities with the North American species Opisthias rarus, particularly in mandibular structure and dentition. However, a unique combination of cranial and dental features justifies its recognition as a distinct taxon. Phylogenetic analyses based on recent datasets of eusphenodontians recover this taxon within a lineage of terrestrial opisthodontians distributed across Laurasia during the Late Jurassic. The presence in Portugal of a form close to Opisthias rarus supports hypotheses of episodic faunal connectivity between North America and southwestern Europe across the proto-North Atlantic during the Kimmeridgian–Tithonian interval, followed by regional differentiation. The exceptional preservation of this specimen not only provides new insights into the anatomy of early opisthodontians but also expands the known geographic range of this poorly represented group into the Iberian landmass and reinforces the Lusitanian Basin as a key region for understanding Late Jurassic vertebrate diversity and paleobiogeography. Moreover, this represents the first definitive record of sphenodontians in the Iberian landmass, together with forms from the UK, suggesting a previously underestimated diversity of terrestrial sphenodontians in Europe and expanding our understanding of their ecological and evolutionary roles.

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6.7.26 , , , , 0 comentarios

Os diplodocoideos como chave para compreender o turnover faunístico da transição Jurássico-Cretáceo no XII Congresso Nacional de Geologia


O XII Congresso Nacional de Geologia de Portugal realizou-se nos passados dias 21 a 26 de Junho, na cidade de Évora. Naquela que é considerada a capital do Alentejo português, dotada de centro histórico classificado como património mundial da UNESCO, alguns membros do GBE-UNED apresentaram os resultados mais recentes das suas investigações.

A comunicação intitulada "Diplodocoidea (Sauropoda) as key to understanding the environmental and ecological context of the Jurassic/Cretaceous transition", da autoria de Joana Órfão (IDL-FCUL, GBE-UNED) e co-autores, teve como objetivo demonstrar como o registo fóssil de diplodocoides pode ajudar a compreender melhor o turnover faunístico da transição Jurássico/Cretácico. Através da aplicação de um conjunto integrado de metodologias analíticas ajustadas a estudos de paleodiversidade e paleobiogeografia, demonstrou-se que apesar da diversidade dos diferentes clados de Diplodocoidea terem sido afectados de maneiras distintas pelas alterações ambientais características deste período de transição, a existência de distintas distribuições geográficas para os subclados Flagellicaudata e Rebbachisauridae não estará ligada a factores climáticos. Identificou-se também a existência de um efeito Lagerstätten nas curvas globais de diversidade de Diplodocoidea, ligado à Formação Morrison (Jurássico Superior, Estados Unidos), e que pode ser mitigado através da implementação de metodologias adequadas de estimação, tais como o shareholder quorum subsampling (SQS). Segue em baixo o resumo da comunicação, em inglês.

The Jurassic-Cretaceous boundary (J/K), approximately 145 million years ago, coincided with the gradual opening of the North Atlantic and the Tethys Sea. During this period, there was a general eustatic sea-level rise, accompanied by global cooling, a general increase in precipitation and more pronounced seasonality in certain parts of the planet. These environmental shifts had a profound impact on marine and terrestrial life, evident in a phenomenon of faunal turnover and a global sharp diversity decline that are well documented in the fossil record. Larger and more specialised terrestrial taxa such as Sauropoda, a diverse group of large herbivorous dinosaurs, were disproportionately affected by these changes. Notably, iconic Late Jurassic neosauropod clades such as Diplodocinae and Camarasauridae started to decline and/or went extinct during the J/K transition, whereas Titanosauriformes and Rebbachisauridae began to diversify and would later dominate Cretaceous landscapes. Herein, we focus on the sauropod clade Diplodocoidea and demonstrate the potential of its fossil record to advance our understanding of the J/K faunal turnover, by applying an integrated approach comprising paleobiogeographic and paleodiversity methodologies. We demonstrate that the main Diplodocoidea subclades were differently affected by the J/K environmental changes, with Late Jurassic Flagellicaudata declining markedly whereas Rebbachisauridae persisted until the Early to mid-Cretaceous. Additionally, and despite apparent differences in paleogeographic distribution, the climatic niche space occupied by both clades is seemingly identical, suggesting a possible niche takeover mechanism within Diplodocoidea. Finally, we compare our paleodiversity estimates with those from previous studies in literature, while also assessing the influence of sampling biases in our results. Notably, we recover a Lagerstätten effect for the Morrison Formation (Upper Jurassic, USA) that can be mitigated through adequate methodological techniques such as Shareholder Quorum Subsampling.

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3.7.26 , , , , , 0 comentarios

Resumo do XII Congresso Nacional de Geologia em Évora (Portugal)


No passado dia 21 a 26 de Junho, realizou-se o XII Congresso Nacional de Geologia em Évora. Neste congresso foram apresentados vários trabalhos que resultam da coloboração de vários anos entre o Instituto Dom Luiz da Faculdade de Ciências da Universidade de Lisboa, Museu Nacional de História Natural e da Ciência e o Grupo de Biología Evolutiva-UNED.

Durante este encontro, foram apresentados vários resumos centrados no estudo dos vertebrados do Jurássico Superior de Pombal (Andrés e Junqueira), em estudos morfo-funcionais e de análises de diversidade sobre os dinossáurios saurópodes, descrição de um novo crânio de cetáceo proveniente do Miocénico português, e um estudo centrado na inventariação e caracterização das coleções de vertebrados miocénicos do Museu Nacional de História Natural e da Ciência de Lisboa. Alexandre Fonseca consegue ainda o Prémio de Melhor Comunicação oral com o trabalho intitulado: "Appendicular myological reconstruction and functional analysis of Lourinhasaurus alenquerensis (Camarasauridae, Sauropoda)". Aqui deixamos a lista de trabalhos apresentados pelos membros do GBE-UNED:
18.5.26 , , , 0 comentarios

Os dinossáurios gigantes de Pombal foram ao Fórum Nacional dos Clubes Ciência Viva na Escola

Pedro Mocho (IDL & DCTE, FCUL; MNHNC; GBE-UNED) no Fórum Nacional dos Clubes Ciência Viva na Escola a falar sobre o Património Paleontológico de Pombal

No passado mês de março estivemos no Fórum Nacional dos Clubes Ciência Viva na Escola realizado em Santarém (Portugal) para falar dos dinossáurios saurópodes do Jurássico Superior de Portugal. Estes dinossáurios gigantes herbívoros e quadrúpedes, caracterizavam-se pelos seus pescoços e caudas compridas, e apresentam um registo abundante no Jurássico Superior de Portugal. 

Trabalhos paleontológicos que decorreram na jazida da Junqueira em 2015 com um grande dinossáurio saurópode

Esta atividade contou com o paleontólogo Pedro Mocho (IDL & DCTE, FCUL; MNHNC; GBE-UNED) na qual tivemos a possibilidade de falar dos trabalhos de campo conduzidos nos últimos anos nas Jazidas da Junqueira (Santiago de Litém), Monte Agudo (Vila Cã) e Mouriscas (Pombal). Os trabalhos de escavação paleontológica, Conservação e Restauro e investigação tem resultado de uma colaboração de vários anos entre o Grupo de Biología Evolutiva da UNED, Museu Nacional de História Natural e da Ciência, Instituto Dom Luiz da Faculdade de Ciências da Universidade de Lisboa, e a Universidade Complutense de Madrid. Durante esta atividade aproveitámos para colocar em evidência o enorme valor do Património Paleontológico de Pombal, e o seu potencial para o desenvolvimento da região.

Trabalhos paleontológicos que decorreram na jazida de Monte Agudo (Vila Cã) em 2022 com um dos maiores dinossáurios saurópodes encontrados na Europa.

Os dinossáurios saurópodes encontrados nestas jazidas em Pombal caracterizam-se pelo seu tamanho gigante, e correspondem a alguns dos maiores exemplares encontrados no Jurássico Superior de Portugal. Estes dinossáurios possuem algumas características morfológicas que nos permitem relacionar com o grupo Brachioasauridae, que inclui espécies como Giraffatitan brancai, Brachiosaurus altithorax e Lusotitan atalaiensis. A descoberta destes exemplares teve um impacto nos media relevante em 2022, despertando o interesse da grande emissora BBC, que dedicou um episódio (Ep. 5: Island of Giants) da série “Walking with Dinosaurs” recentamente emitida.

Os dinossáurios saurópodes de Pombal estiveram no Episódio 5: Island of Giants) de “Walking with Dinosaurs” (BBC)

Na semana passada estivemos em Pombal para continuar com os trabalhos de Conservação e Restauro, que contaram com os especialistas do Grupo de Conservação GBE/Facultad de Bellas Artes da Universidade Complutense e IDL.FCUL/MNHNC. Estes trabalhos têm contado com a colaboração da Câmara Municipal de Pombal, das Juntas de Freguesia de Santiago de Litém e Vila Cã, e de todos proprietários dos terrenos intervencionados.

Trabalhos de Conservação e Restauros de costelas de saurópode com quase três metros de comprimento provenientes de Monte Agudo (Vila Cã)

Para mais informações sobre os saurópodes de Pombal e arredores, consultar:
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Comparação funcional dos membros anteriores dos dinossauros saurópodes Lourinhasaurus e Camarasaurus na XXIV EJIP


PT: A XXIV edição do EJIP, em Bogarra, contou com a participação de membros da Faculdade de Ciências da Universidade de Lisboa (FCUL), como é exemplo a apresentação por poster “Show me your moves! A functional comparison of the forelimbs of Lourinhasaurus and Camarasaurus using an open-source musculoskeletal workflow”, por Alexandre Fonseca. Este trabalho explora a morfologia functional do membro anterior de um distintivo camarassáurio de Portugal, comparando-o com Camarasaurus grandis através de técnicas de paleontologia virtual. Entre os resultados estão patentes diferenças fucnionais importantes entre os membros anteriores de ambos os taxa. Esta apresentação por poster foi distinguida com o prémio de “Mejor comunicación en formato póster”.

SP: La XXIV edición del EJIP, celebrada en Bogarra, contó con la participación de miembros de la Facultad de Ciencias de la Universidad de Lisboa (FCUL), como por ejemplo la presentación en póster «Show me your moves! A functional comparison of the forelimbs of Lourinhasaurus and Camarasaurus using an open-source musculoskeletal workflow», a cargo de Alexandre Fonseca. Este trabajo explora la morfología funcional de las extremidades delanteras de un camarasaurio característico de Portugal, comparándolo con Camarasaurus grandis mediante técnicas de paleontología virtual. Entre los resultados se observan importantes diferencias funcionales entre las extremidades delanteras de ambos taxones. Esta presentación en formato póster fue galardonada con el premio a la «Mejor comunicación en formato póster».

Lourinhasaurus alenquerensis is a Portuguese species of camarasaurid sauropod distinguished from Camarasaurus by several osteological features, some of them found in the appendicular skeleton. Hitherto, the functional implications of the camarasaurid forelimb have not been experimentally assessed. Here, we present a digital framework to address this. Within a 3D environment (Blender; version 4.2.0), a musculoskeletal rig was built to test how reconstructed soft tissues (in this case, musculature) constrain the movement of the forelimb of two camarasaurid species, Lourinhasaurus alenquerensis and Camarasaurus grandis. The rigs were animated to simulate various forelimb movements. Then, a Python (version 3.12.10) script was developed to automate the analysis. For each frame of animation, the script calculates the strain ratio of each reconstructed muscle, and outputs it. This method enabled the identification of muscle tension limit, therefore informing about overall ranges of motion. The results obtained through these analyses provide evidence supporting greater ranges of motion in the forelimb of Lourinhasaurus alenquerensis than in the forelimb of Camarasaurus grandis, mainly due to the wider glenoid articulation and lower torsion of the humeral shaft in Lourinhasaurus compared to Camarasaurus grandis. These novelties, together with the previously known distinctions between the appendicular skeletons of Lourinhasaurus alenquerensis and the genus Camarasaurus (such as the proportionally longer forelimb), support the hypothesis that Lourinhasaurus alenquerensis was a camarasaurid with unique locomotor adaptations within the clade. Finally, the developed workflow within Blender and Python script provides researchers, for the first time, a potential open-source option for running musculoskeletal analyses. Further development of this methodology into a Blender add-on will allow free use of these tools in the future.

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  • Referencia: Fonseca, A., Vidal, D., Ortega, F., Mocho, P. (2026) Show me your moves! A functional comparison of the forelimbs of Lourinhasaurus and Camarasaurus using an open-source musculoskeletal workflow. Libro de resúmenes del XXIV Encuentro de Jóvenes Investigadores en Paleontología (EJIP), Bogarra, Albacete.
27.11.25 , , , 0 comentarios

La diversidad de saurópodos de la Formación Morrison en el 85th Annual Meeting de la SVP


La 85th Annual Meeting de la Society of Vertebrate Paleontology se celebró entre el 11 y el 15 de noviembre en la ciudad inglesa de Birmingham. Entre homenajes a Black Sabbath y tributos a la ciudad de Tolkien, también hubo tiempo para que miembros del Instituto Dom Luiz (Universidad de Lisboa), del Grupo de Biología Evolutiva (UNED) y del Institut Catalá de Paleontologia Miquel Crusafont (UAB) presentaran una comunicación titulada "The Morrison Fm. (Late Jurassic, USA) Sauropoda diversity: a blink into the (global) past". Esta presentación en formato póster versó sobre los niveles de diversidad de saurópodos que pueden encontrarse en esta unidad geológica, caracterizada por su notable extensión cronogeográfica. Joana Órfão y sus coautores intentaron evaluar el impacto de la inclusión de los hallazgos pertenecientes a la formación Morrison en las curvas de diversidad del grupo de saurópodos Diplodocoidea mediante modelos GLS. Los resultados obtenidos muestran que esta formación podría producir un efecto Lagerstätten (una inflación artificial de la diversidad causada por la sobrerrepresentación de algunos taxones) en los patrones de diversidad de los diplodocoideos cuando estos se estiman con métricas no corregidas. Sin embargo, este efecto no se observa en los patrones obtenidos a partir de estimaciones que mitigan los efectos del sobremuestreo, por ejemplo, mediante el método de quorum subsampling. A continuación se presenta el resumen completo de la comunicación:

The Upper Jurassic Morrison Formation in the western US has long been a rich source of paleontological discoveries. These continental sediments were deposited across 1.2 million square km of alluvial plains with rivers, floodplains, and seasonal lakes. Its wide extent and exceptional fossil preservation have made the Morrison Fm. one of the most intensively studied geological units globally. Although dinosaurs from the Morrison Fm. have been known since the late 19th century, discoveries continue to enhance our understanding of Late Jurassic biodiversity. Although the high diversity in the Morrison Fm. is generally accepted as genuine, the extent to which sampling bias and fossil record limitations may distort diversity estimates remains unclear. Sauropod dinosaurs are especially abundant in the Morrison Fm., with genera such as Camarasaurus, Diplodocus, Brachiosaurus, and Apatosaurus among its most iconic. Many sites within the formation have produced fossils from multiple coexisting sauropod taxa. The global peak in sauropod diversity during the Late Jurassic, often cited in the scientific literature, appears to be largely driven by discoveries from the Morrison Fm. However, reconstructing the true sauropod diversity in this formation is challenging. Factors such as stratigraphic variation, taphonomic processes, ontogenetic changes, evolutionary dynamics, and environmental influences may obscure accurate diversity estimates. Paradoxically, despite the formation's extensive fossil record and long depositional history, some researchers argue that its sauropod diversity is still underestimated. This raises caution about using formations like the Morrison Fm. as the basis for extrapolating global diversity patterns. In light of this, we investigated whether a Lagerstätten effect associated with the Morrison Fm. might be influencing global Late Jurassic Diplodocoidea diversity patterns. We estimated global diversity for this clade both with and without Morrison Fm. occurrence data and used a GLS-based modeling approach to evaluate the roles of abiotic factors, sampling biases, and preservational biases in shaping these paleodiversity trends (e.g. tetrapod bearing formations and collections, emerged land area, paleotemperature, sea level, stage length). Preliminary results from our best-fitting models support the hypothesis that the Morrison Fm. exerts a Lagerstätten effect, identifying it as a significant influence on global Diplodocoidea diversity curves.

Funding Sources FCT Portugal: UI/BD/151441/2021 (PhD grant) and CEECIND/00726/2017; Spanish Ministry of Science, Innovation and Universities: JDC2023-050836-I (Juan de la Cierva grant).

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21.11.25 , , , , , , , , , 0 comentarios

Un resumen de la participación del GBE en el 85th Annual Meeting de la SVP


Un año más se ha celebrado uno de los congresos más importantes de la paleontología de vertebrados, nos referimos, por supuesto, al 85th Annual Meeting of the Society of Vertebrate Paleontology (SVP para los amigos) acogido este año en la ciudad inglesa de Birmingham. El grueso del congreso (sin incluir las múltiples salidas de campo) discurrió entre los días del 11 al 15 de noviembre en el International Convention Centre contando con una asistencia multitudinaria, participantes de todas las partes del mundo y centenares de comunicaciones orales y pósters, siendo una de las reuniones de la SVP de mayor asistencia en años recientes.


Además de varias sesiones paralelas de comunicaciones orales y las tradicionales sesiones de poster o la cena de clausura con su entrega de premios, también tuvieron lugar multitud de mesas redondas, entrevistas, exposiciones de paleoarte y editoriales y una inauguración en la que se visitó el Lapworth Museum of Geology de la Universidad de Birmingham. Sin embargo, eventos como las célebres subastas de la SVP no se celebraron por primera vez en décadas debido a la situación arancelaria de los EEUU.


Miembros del Grupo de Biología Evolutiva de la UNED han participado en este congreso con diversas contribuciones sobre los últimos avances en diferentes linajes de dinosaurios que están llevando a cabo los integrantes del grupo. A continuación, os dejamos con el listado de los trabajos presentados (estad atentos porque iremos ampliando cada uno de ellos en los próximos días): 


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28.10.25 , , 0 comentarios

Evaluación de la función del cuerno de Ceratosaurus mediante FEA en las XL Jornadas de la SEP


Ceratosaurus es un dinosaurio terópodo del Jurásico Superior que presenta un cuerno nasal único y prominente. Fue descrito inicialmente por O.C. Marsh en 1884 como un "cuerno alto y afilado, que debió haber formado un arma muy poderosa para el ataque y la defensa". Estudios más recientes han propuesto que el cuerno de Ceratosaurus pudo haber sido usado como un elemento de exhibición. Sin embargo, hasta la fecha, ningún estudio ha investigado directamente la función del cuerno nasal de Ceratosaurus. Un estudio que emplea análisis de elementos finitos comparó el cráneo de Ceratosaurus con el de Allosaurus, un terópodo que carece de cuerno nasal, con el objetivo de evaluar la función del cuerno de Ceratosaurus. Ambos terópodos presentan resultados muy similares en los patrones de distribución de stress, lo que sugiere que Ceratosaurus no poseía adaptaciones consistentes relacionadas con un uso del cuerno como arma, siendo más probable que este cumpliera una función de exhibición. Esta investigación fue presentada en las XL Jornadas de la Sociedad Española de Paleontología, y el resumen es el siguiente:

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Ceratosaurus is a Late Jurassic theropod dinosaur that presents a unique and preeminent nasal horn. It was initially described by O.C. Marsh in 1884 as a “high, trenchant horn, which must have formed a most powerful weapon for offense and defense.”. More recent studies have hypothesized that the horn of Ceratosaurus may have been used as a display feature. However, to date, no study has directly investigated the function of the Ceratosaurus nasal horn. A study using Finite Element Analysis (FEA) compared the skull of Ceratosaurus with that of Allosaurus, a theropod lacking a nasal horn, to test the function of the Ceratosaurus horn. Both theropods showed very similar results in their stress distribution patterns, suggesting that Ceratosaurus did not possess any adaptations consistent with a weaponized use of its horn and that it was more likely a display structure. This research was presented at the XL Conference of the Sociedad Española de Paleontología and the abstract is as follows:

Ceratosaurus was a Late Jurassic theropod presenting a prominent and unique nasal horn. The function of the Ceratosaurus’ nasal horn has been initially interpreted as a weaponized structure. More recent studies proposed that it was a display structure. Finite Element Analysis (FEA) has been previously used to investigate the function of horns and crests in the theropods Majungasaurus, Carnotaurus and Sinosaurus. However, FEA has not yet been used to investigate the functional role of Ceratosaurus’ nasal horn. In this study, we developed 2D lateral view models of Ceratosaurus and Allosaurus skulls from scratch in ANSYS based on skull reconstruction from the Museu Nacional de História Natural e da Ciência. Because the horn is transversally poorly developed, we created two models for Ceratosaurus, one with the horn and one without. Alligator cortical bone material properties were applied to the models. The models were constraints at the posterior end of the skull, from the dorsal margin of the squamosal to the ventral end of the quadrate. An arbitrary load of 3000N was applied vertically to the horn of Ceratosaurus. For the Allosaurus and Ceratosaurus without horn models, the load was scaled and applied vertically to the dorsal surface of the nasal, between the anterior margin of the antorbital fenestra and the posterior margin of the naris. All models show similar results, with high stress concentration observed in the postorbital and the cheek region. The comparative analysis suggests that Ceratosaurus’ nasal horn may not have had specific adaptations to absorb or dissipate stress associated with its use as a weaponized structure. Based on these results, the horn of Ceratosaurus is interpreted as a display structure. However, due to the limitations of 2D analyses in capturing complex shapes, such as theropod skulls, future 3D analyses are necessary to test these results.

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Un resumen de la participación del GBE en las XL Jornadas de la SEP


Como cada año, durante el mes de octubre han tenido lugar las Jornadas de la Sociedad Española de Paleontología (SEP). En esta ocasión, el destino elegido para la celebración de la cuadragésima edición de estas jornadas ha sido Aracena (Huelva), debido a su relevancia dentro del contexto geológico en el que se encuentra: el Parque Natural de la Sierra de Aracena y Picos de Aroche (Sierra Morena).


Las jornadas se han llevado a cabo entre los días 7 y 10 de octubre en las instalaciones del Teatro Sierra de Aracena y han contado con la asistencia de alrededor de 150 congresistas y la presentación de más de 130 comunicaciones, tanto de forma oral como en formato póster.


Diversos miembros del Grupo de Biología Evolutiva (GBE) de la UNED han participado este año con diversas contribuciones. A continuación, os dejamos un listado de los trabajos presentados (del cuál se irá ampliando información en los sucesivos días):
25.9.25 , , 0 comentarios

Nuevos datos sobre las tortugas de Riodeva (Teruel) en las X Jornadas Internacionales de Salas de los Infantes


Un único individuo de tortuga había sido, hasta ahora, documentado en la bien conocida localidad del Jurásico Superior de Barrihonda-El Húmero, en Riodeva (Teruel). Se trataba del holotipo de Riodevemys inumbragigas, el primer pleurostérnido definido en el registro español. Hasta ahora esta especie era conocida exclusivamente mediante ese espécimen, correspondiente a un espécimen adulto. Un ejemplar hasta ahora inédito de Pleurosternidae de esa misma localidad ha sido presentado en las X Jornadas Internacionales sobre Paleontología de Dinosaurios y su Entorno, recientemente celebradas en Salas de los Infantes (Burgos). Al igual que el individuo previamente documentado, se trata de un esqueleto parcial, destacando, por su preservación, el caparazón. Su potencial atribución a una misma especie y, por tanto, las posibles implicaciones para conocer la ontogenia de un miembro de este linaje, son evaluadas. El resumen de esta contribución, titulada “The second individual of Pleurosternidae from the Tithonian Barrihonda-El Humero site (Riodeva, Teruel)”, es el siguiente:

One of the main lineages of stem turtles (i.e., Testudinata not attributable to the crown group Testudines) identified in the Iberian record is that of Paracryptodira. In this region, it is exclusively represented by members of the Pleurosternidae. Pleurosternidae is the only group of freshwater turtles identified in the Upper Jurassic record of both North America and Europe, showing a relatively high diversity in both regions. The North American record of this lineage is restricted to the Upper Jurassic. However, Pleurosternidae shows a notably wider temporal distribution in Europe, surviving at least until the last stage of the Lower Cretaceous (i.e., the Albian).
The information on the European members of Pleurosternidae was, until a few years ago, very limited. However, recent studies and, especially, the description of several new forms, allowed improving the knowledge on the diversity, systematic, and stratigraphic and palaeobiogeographic distributions of the forms that inhabited this continent. Although several forms are currently known for the Spanish record, the first described there was Riodevemys inumbragigas. It comes from the Kimmeridgian or Tithonian Barrihonda-El Humero fossil site, located in Riodeva, in the Teruel Province (South Iberian Basin). Other vertebrates found at this site include the sauropod Turiasaurus, the stegosaurid Dacentrurus, and the ornithopod Oblitosaurus.
Riodevemys inumbragigas was defined by a partial skeleton of an adult individual, including the almost complete shell, as well as several bones of the scapular and pelvic girdles. No other specimen has been attributed to it so far.
An unpublished partial skeleton of a turtle from the type locality of Riodevemys inumbragigas is presented here. It corresponds to a juvenile individual. Its attribution to Pleurosternidae is justified here. In fact, it is probably attributable to Riodevemys inumbragigas. However, differences in several shell characters relative to the holotype of this species are recognized. The possibility that some of these differences are due to ontogeny, but others to individual variability, are evaluated here considering the intraspecific variability known for Pleurosternidae.

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8.9.25 , , , 0 comentarios

El impacto del clima en los patrones de biodiversidad de los saurópodos diplodocoideos en el IV CPEG/III CPB


Entre el 27 de julio y el 1 de agosto, se celebraron conjuntamente la cuarta conferencia Crossing the Paleontological-Ecological Gap y el tercer simposio Conservation Paleobiology, en la Universidad de Zúrich, Suiza. El objetivo de estos dos encuentros internacionales es reunir a investigadores de paleontología y ecología para promover el intercambio de ideas, datos y métodos que se utilizan en ambas disciplinas, pero rara vez de forma conjunta. Del mismo modo, también pretenden fomentar la inclusión de datos paleobiológicos y ecológicos en el desarrollo de estrategias y planes de conservación, gestión y recuperación de la biodiversidad.


El primer día de la conferencia se dedicó íntegramente a talleres sobre diferentes temas, desde el desarrollo de buenas prácticas de ciencia abierta y el uso del aprendizaje profundo para análisis macroevolutivos, hasta el uso de la narración como herramienta de comunicación científica y la importancia de pensar más allá del modelo de «trabajo para toda la vida». Los cuatro días siguientes se dedicaron a comunicaciones orales (incluidas ponencias magistrales), y la sesión de comunicaciones en formato póster tuvo lugar el segundo día de la conferencia. En ella, el Grupo de Biología de la UNED estuvo representado por la estudiante de doctorado Joana Órfão (IDL/FCUL y GBE), que presentó una comunicación titulada «Climate's impact on the biodiversity patterns of Diplodocoidea during the Jurassic-Cretaceous transition» (El impacto del clima en los patrones de biodiversidad de Diplodocoidea durante la transición del Jurásico al Cretácico), parte de su tesis doctoral.


Este estudio explora los patrones de diversidad a largo plazo de los Diplodocoidea, un importante grupo de dinosaurios herbívoros de cuello largo. Mediante el análisis de registros fósiles, los investigadores descubrieron que dos subgrupos, los Dicraeosauridae y los Diplodocidae, alcanzaron su máxima diversidad durante el Jurásico tardío, pero disminuyeron drásticamente a lo largo del límite entre el Jurásico y el Cretácico. Por el contrario, los Rebbachisauridae cobraron importancia durante el Cretácico temprano y medio, lo que sugiere un cambio en los tipos de saurópodos que dominaron a lo largo del tiempo. Para comprender qué impulsó estos cambios, los investigadores también analizaron los datos climáticos y descubrieron que cada subgrupo de Diplodocoidea prefería condiciones ambientales ligeramente diferentes. Esto indica que el clima pudo haber desempeñado un papel importante en la configuración del lugar y el momento en que estos dinosaurios podían prosperar, y ayuda a explicar la transición en el dominio de los saurópodos a lo largo de los períodos geológicos. El resumen es el siguiente:

Reconstructing the diversity of life through deep time is crucial for understanding the evolution of life, as well as the mechanisms behind extinction and recovery. The fossil record, in particular, provides insights into the factors influencing biodiversity, such as past climate and landmass distributions. Sauropoda, a major clade of non-avian dinosaurs, offers a unique opportunity to study long-term biodiversity patterns. These large herbivores, with diverse lineages and significant ecological roles, have an abundant fossil record and a global distribution. Research suggests a latitudinal constraint on their distribution, a peak in diversity during the Kimmeridgian-Tithonian linked to the radiation of Neosauropoda, and a shift in faunal composition during the Jurassic-Cretaceous transition. Diplodocoidea is a neosauropod group with three main subclades—Dicraeosauridae, Diplodocidae, and Rebbachisauridae—showing recognizable cranial anatomy despite varied morphology. This group underwent a faunal shift during the Jurassic-Cretaceous transition, with Rebbachisauridae seemingly replacing Flagellicaudata (Dicraeosauridae + Diplodocidae) and extending into the Early-Mid Cretaceous. In this study, we examine Diplodocoidea biodiversity patterns at the genus level using both raw taxonomic diversity and SQS (Shareholder Quorum Subsampling) metrics. Our results replicate previous findings, revealing distinct geochronological diversity patterns for Rebbachisauridae and Flagellicaudata, suggesting these patterns are biological rather than sampling artifacts. Dicraeosauridae and Diplodocidae show a diversity peak during the Kimmeridgian-Tithonian, followed by a trough across the Jurassic-Cretaceous boundary. Rebbachisauridae presents consistently high diversity from the Barremian through the Cenomanian, peaking in the Aptian (or Cenomanian if uncorrected). We also assessed the influence of climate variables as drivers of Diplodocoidea biogeographic distribution, using PCA, UMAP and t-SNE methods. Our findings suggest that each clade occupied distinct climatic niches, indicating different ecological constraints and highlighting the role of climate in the Jurassic-Cretaceous sauropod faunal transition.

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11.7.25 , , , 0 comentarios

Nuevos ejemplares de escamosos del Jurásico de Guimarota en el XXII Annual Meeting de la EAVP


Miembros del Grupo de Biología Evolutiva de la UNED han presentado durante la 22a edición de la EAVP la comunicación titulada “New squamate specimens from the Kimmeridgian Guimarota fossil site (Portugal)”. En esta comunicación se han presentado varios restos vertebrales correspondientes a un lagarto escamoso (Squamata) de Jurásico Superior de Portugal. Así, se hace una descripción anatómica y atribución sistemática preliminar de dichos elementos vertebrales, siendo atribuidos a Anguimorpha. A continuación, os dejamos el resumen perteneciente a este trabajo:

The former Guimarota coal mine, located near Leiria, in the west-central region of Portugal, is recognized as one of the most significant Upper Jurassic microvertebrate fossil localities worldwide. The vertebrate-bearing lignite coal layers have been interpreted as belonging to the Alcobaça Formation and dated to the early Kimmeridgian based on ostracods. This site is particularly renowned for its abundant and diverse fossil record of early mammalians, but a wide array of other vertebrates, including actinopterygians, amphibians, lepidosaurs, turtles, crocodyliforms, dinosaurs, and pterosaurs, have also been recovered. A set of previously undescribed, relatively well-preserved, isolated vertebrae from Guimarota, housed in the Museu Geológico (MG) in Lisbon and mislabelled as belonging to theropod dinosaurs, is described here, and its taxonomic identification is reassessed. These specimens include a cervical (MG 28959) and four dorsal (MG 28954, MG 28955, MG 28958, MG 28960) vertebrae, which are reinterpreted as belonging to small squamates. This interpretation is based on the procoelous morphology of the centra, the presence of anteroposteriorly narrow and dorsoventrally elongate paradiapophyses, and a poorly developed zygosphene-zygantrum complex (recognized in some dorsal vertebrae). The mostly straight axis of the cotyle-condyle system and the internal structure, composed of several small cavities visible in both the centrum and neural arch, indicating non-pachyostotic vertebrae, are features shared with most Pythonomorpha. However, the poorly developed zygosphene-zygantrum complex allow us to exclude the possibility that the specimens from Guimarota belong to this clade. These specimens share several features with other vertebrae from Guimarota previously attributed to indeterminate anguimorphs, including anteriorly broadened centra with ventrally smooth surfaces, as well as a shortened, broad condyle and a broad, elliptical cotyle. Based on these features, the isolated vertebrae described here are reinterpreted as belonging to Anguimorpha. The study of these specimens contributes to our understanding of the squamate diversity at Guimarota and provides new data to better characterize the poorly documented axial skeleton of the anguimorphs from this locality.

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8.7.25 , , , , , , 0 comentarios

Un resumen de la participación del GBE en el XXII Annual Meeting de la EAVP


Como cada año, entre finales de junio y principios de julio, se celebra el congreso internacional de la European Association of Vertebrate Palaeontologists (EAVP),que en esta ocasión, se ha celebrado en la ciudad de Cracovia (Polonia). Se trata de la vigesimosegunda edición de estas importantes jornadas paleontológicas, y han discurrido entre los días 30 de junio y 5 de julio en las instalaciones del Museo Krzysztofory y el Instituto de Sistemática y Evolución de los Animales (PAS). Varios miembros del GBE de la UNED han participado este año con algunas contribuciones. A continuación, os dejamos un listado de los trabajos presentados (del cuál se irá ampliando información en los sucesivos días):
21.4.25 , , , 0 comentarios

Más iguanodontios en el Jurásico Superior del archipiélago europeo


Los iguanodontios son un grupo de dinosaurios ornitópodos con un gran enorme éxito evolutivo que se conocen desde la parte final del Jurásico y que poblaron las distintas tierras emergidas del planeta hasta el fin de la era Mesozoica. El registro ibérico del Jurásico Superior de ornitópodos iguanodontios juega un papel muy importante en la historia evolutiva del grupo y está conformado por cuatro especies: Eousdryosaurus nanohallucis, Draconyx loureiroi, Oblitosaurus bunnueli y Hesperonyx martinhotomasorum. Sin embargo, a este elenco de formas bípedas de dinosaurios herbívoros se le ha unido una nueva forma de iguanodontio de tamaño parecido a Oblitosaurus y la forma del registro de Norteamérica Campotosaurus, para complicar la cosa. Los restos fósiles de este nuevo ejemplar han sido publicados hace unas semanas en la revista científica Journal of Systematic Palaeontology. Además, se han descrito en este trabajo restos apendiculares de otros individuos de menor tamaño y edad que han podido relacionarse con esta nueva y desconocida forma del registro ibérico. Os dejamos aquí el resumen del trabajo:

The Upper Jurassic beds of the Lusitanian Basin in central Portugal yield diverse dinosaurian fauna, dated to the Kimmeridgian–Tithonian interval. Saurischian dinosaurs are, overall, more abundant than their ornithischian counterparts, in terms of both specimens collected and species recognized. Iguanodontians are so far represented by the styracosternan Draconyx loureiroi, the dryosaurid Eousdryosaurus nanohallucis and the enigmatic dryomorphan Hesperonyx martinhotomasorum. Here we aim to highlight the diversity of this clade in the Late Jurassic of Portugal, presenting evidence for yet another species of ankylopollexian iguanodontian dinosaur, represented by the specimen SHN.JJS.015, which is housed at the Sociedade de Historia Natural, Torres Vedras. Detailed comparisons rule out attribution to previously known taxa, and phylogenetic analyses that include SHN.JJS.015 indicate early-diverging ankylopollexian affinities for this specimen. As there is no robust diagnosis, we do not erect a new formal species for it at this stage. Nevertheless, this specimen represents a previously unreported taxon that highlights greater diversity than previously estimated among the iguanodontians of the Late Jurassic and highlights the importance of Europe in diversification and dispersal events of this clade. A series of smaller, isolated femora from the same sub-basin as SHN.JJS.015 may represent the same taxon, presenting evidence of thriving communities of ankylopollexians during the Kimmeridgian–Tithonian interval in Portugal.


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1.4.25 , , 0 comentarios

Un nuevo crocodiliforme maquimosaurino del Jurásico Superior de Alpuente en el 5th Palaeontological Virtual Congress


Durante el mes de marzo tuvo lugar la quinta edición del Palaeontological Virtual Congress, donde se presentó la comunicación: "A machimosaurid crocodyliform from the Tithonian of the Villar del Arzobispo Formation at Alpuente (Valencia Spain)" realizada por Arturo Gamonal, Maite Suñer, Iván Narváez y Francisco Ortega. Este trabajo presenta los restos de un nuevo crocodiliforme maquimosaurino del Jurásico Superior de Alpuente. Estos nuevos restos son elementos poscraneales, con varios centros vertebrales, el sacro completo y un fémur, además de un fragmento de mandíbula. Se han comparado estos restos con los diversos talatosuquios del Jurásico Superior europeo, demostrando las similitudes de estos restos con la tribu Machimosaurinii, haciendo de estos restos los primeros elementos postcraneales de este taxón en España. El resumen es el siguiente:

Teleosauroidea were a diverse group of marine crocodyliforms that thrived during the Early and Middle Jurassic, having a decline in diversity towards the end of the Upper Jurassic. Few remains of this group have been recovered beyond the Jurassic-Cretaceous boundary. In this study, we present the remains of a large teleosauroid found in Alpuente (Valencia, Spain).
The material was recovered from the Corral de Marín fossil site, located at the base of the Villar del Arzobispo Formation, and dates from the lowermost Tithonian. It is therefore one of the few teleosauroids present during this age. The available remains include both cranial and postcranial elements: five dorsal vertebrae, a sacrum, four caudal vertebrae, a femur, a partial lower jaw, and osteoderms.
Comparative analysis with other teleosauroids from the Upper Jurassic of Europe reveals morphological features that enable its tentative classification within the Machimosaurini tribe. Key characters include the presence of three sacral vertebrae (two true sacrals and one caudosacral), the distinctive morphology of the Meckelian groove in the mandible, and the ornamentation of the teeth preserved in the alveoli of the lower jaw. The available characters allow for a preliminary assessment of the taxonomic status of the material, which exhibits unique features within the context of the Machimosaurini. This finding potentially represents the first record of skeletal remains for Machimosaurini in the Tithonian of Europe.

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