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Cunha, P. P., Mateus O., & Antunes M. T. (2004).  The sedimentology of the Paimogo dinosaur nest site (Portugal, Upper Jurassic). 23 rd IAS Meeting of Sedimentology. 93., Coimbra, Portugal Abstractcunha_p_p_2004_-_the_sedimentology_of_the_paimogo_dinosaur_nest_site_portugal10467.pdf

Sedimentological features of the Paimogo site, 6 km NNW of Lourinhã, western central Portugal are presented. More than one hundred theropod dinosaur eggs (some containing embryo bones) ascribed to Lourinhanosaurus antunesi Mateus 1998, three crocodilian eggs and some other fossils were found at the 32 m2 excavated area of the egg-bearing horizon (Mateus et al., 1998). The stratigraphic position of the site is the Praia Azul member (Lourinhã Formation), roughly corresponding to the Kimmeridgian-Tithonian boundary or, more likely lowermost Tithonian. The maximum flooding surface of the basinal transgressive event where the horizon is located corresponds to the base of the H depositional sequence defined by Pena dos Reis et al. (2000) and probably correlates to the base of sequence Ti1 identified within western European basins (Jacquin et al., 1998), dated as 150 Ma. Possibly during the normal river discharge, the theropods congregated in nesting colonies at the backswamp of an extensive flood plain with small meandering channels and freshwater ponds. There are no evidences that the nest was dug or the eggs buried. The eggs have probably been laid on a flat, shaded, muddy area near the bank of a large pond. It is probable that the eggs have not been actively incubated. The larger number of eggs suggest that they were laid near simultaneously by, at least, six females. The fossil record shows that crocodilians, mammals, gastropods and fish were also present. A flood event occurred when theropod embryos had attained a late stade of ontogenetic development, probably just before hatching. The overflow from a nearby channel flooded the plain, including the area where the eggs had been laid. The sheet flood flowing over the nest resulted into the scattering and breaking up of some dinosaur eggs. Eggshell and embryos skeletal parts fragments were displaced to an adjacent area where, due to hydrodynamic decline, the flow submerged other clutches and moderately dragged their eggs. The flooding caused the drowning of the embryos and covered the eggs with fine-grained sediment, hiding them from predators and scavengers. Hydrodynamic interpretation of the arrangement of the theropod eggs and egg-fragments suggests that the flow came from the NW. When the floodwaters receded, the fine-grained deposits became exposed to subaerial weathering. Although the sediment surface was often wet and small bodies of standing water may still have existed, the sediments were oxidized and plant remains have consequently been destroyed. Some carbonate cementation and redenning resulted from pedogenesis under alternating dry and moist conditions, in a semiarid/ sub-tropical climate under seasonal changing, contrasting conditions. The thick, stratigraphically above and below the nesting horizon mudrocks indicate a long persistence of periodic flooding, alternating with pedogenesis. During the early stages of diagenesis, vertical pressure crushed the eggs. Silt penetration into the inner part of each egg inhibited later flattening during the burial process.

Cunha, P. P., Mateus O., & Antunes M. T. (2004).  The sedimentology of the Paimogo dinosaur nest site (Portugal, Upper Jurassic). 23 rd IAS Meeting of Sedimentology. 93., Coimbra, Portugal Abstract
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Cunha, P. P., Mateus O., & Antunes M. T. (2004).  The sedimentology of the Paimogo dinosaur nest site (Portugal, Upper Jurassic). 23 rd IAS Meeting of Sedimentology. 93–93., Coimbra, Portugal Abstract
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Crespo, V. D., Sequero López C., Rios M., Estraviz López D., Gamonal A., Martino R., Riccetto M., Callapez P., Legoinha P., & Mateus O. (2023).  Revisiting the classical small mammal assemblage from the Eocene site of Silveirinha: a fresh look at old collections. XI Congresso Nacional de Geologia: Geociências e Desafios globaisAt: Universidade de CoimbraVolume: Livro de Resumos, págs 85-86. , Coimbra Abstractcrespov_etal_xicng2023_silveirinha.pdf

O sítio de Silveirinha é uma das localidades de mamíferos mais conhecidas da Paleontologia do Cenozoico de Portugal e da Europa em geral. Graças à sua rica e diversificada associação de mamíferos, com mais de 30 taxa, foi posicionado no Eocénico inferior (início do Ypresiano, MP7, ca. 55,8 M.a.), sendo o local mais antigo da Europa desta Época, devido à presença única de taxa típicos do Paleocénico superior, juntamente com outras espécies já características do Eocénico inferior. Este estudo irá rever o material de pequenos mamíferos deste sítio, conservado na coleção clássica da Universidade Nova de Lisboa, a fim de fazer uma actualização taxonómica à luz das publicações mais recentes.

Costa, F., & Mateus O. (2018).  Alcovasaurus longispinus as a dacentrurine stegosaur (Dinosauria) and contributions to the diagnosis of Dacentrurinae. XVI Annual Meeting of the European Association of Vertebrate Palaeontologists. 50.: Abstract book of the XVI Annual Meeting of the European Association of Vertebrate Palaeontologists, Caparica, Portugal June 26th-July 1st, 2018. Abstract

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Costa, F., & Mateus O. (2018).  Alcovasaurus longispinus as a dacentrurine stegosaur (Dinosauria) and contributions to the diagnosis of Dacentrurinae. XVI Annual Meeting of the European Association of Vertebrate Palaeontologists. 50.: Abstract book of the XVI Annual Meeting of the European Association of Vertebrate Palaeontologists, Caparica, Portugal June 26th-July 1st, 2018. Abstractcosta__mateus_2018_eavp_abstract.pdf

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Costa, F., Silva T., Fernandes J., Calvo R., & Mateus O. (2017).  Retracing the history of a stegosaurian dinosaur discovery in Portugal and the importance of record-keeping in Palaentology. Abstract book of the XV Encuentro de Jóvenes Investigadores en Paleontología/XV Encontro de Jovens Investigadores em Paleontologia, Lisboa, 428 pp.. 119-124. Abstractcosta_et_al_2017_retracing_the_history_-_2017.pdf

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Correia, T., Barcelos L., Nunes T., Riff D., & Mateus O. (2017).  On a titanosaur scapula from the Mar{\'ılia Formation (Upper Cretaceous, Bauru Group) in Campina Verde Town. XXV Congresso Brasileiro de Paleontologia Boletim de Resumos. 77. Abstract
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Correia, T., Barcelos L., Nunes T., Riff D., & Mateus O. (2017).  On a titanosaur scapula from the Marília Formation (Upper Cretaceous, Bauru Group) in Campina Verde Town. XXV Congresso Brasileiro de Paleontologia Boletim de Resumos. 77. Abstractthiago_abstract_brazil_2017.pdf

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Correia, T., Barcelos L., Nunes T., Riff D., & Mateus O. (2017).  On a titanosaur scapula from the Marília Formation (Upper Cretaceous, Bauru Group) in Campina Verde Town. 77. Abstract
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Conti, S., Mateus O., & Sala G. (2021).  Mechanical characterization of tibial bone material of an ostrich. Rossi V., Fanti F., Barbieri G., Cavalazzi B. & Scarponi D. (Editors) 2021. Paleodays 2021. Abstract Book del XXI Convegno della Società Paleontologica Italiana, live virtual edition: 127 pp.. , 15-17 June, Bologna (Italy): University of Bolognaconti_et_al_2021_ostrich_bone.pdf
Conti, S., Tschopp E., Mateus O., Zanoni A., Masarati P., & Sala G. (2022).  Multibody analysis and soft tissue strength refute supersonic dinosaur tail. 12(1), 19245., 2022 Abstractconti_et_al_2022._multibody_analysis_and_soft_tissue_strength_refute_supersonic_dinosaur_tail.pdfWebsite

Sauropod dinosaurs are well known for their massive sizes and long necks and tails. Among sauropods, flagellicaudatan dinosaurs are characterized by extreme tail elongation, which has led to hypotheses regarding tail function, often compared to a whip. Here, we analyse the dynamics of motion of a 3D model of an apatosaurine flagellicaudatan tail using multibody simulation and quantify the stress-bearing capabilities of the associated soft tissues. Such an elongated and slender structure would allow achieving tip velocities in the order of 30 m/s, or 100 km/h, far slower than the speed of sound, due to the combined effect of friction of the musculature and articulations, as well as aerodynamic drag. The material properties of the skin, tendons, and ligaments also support such evidence, proving that in life, the tail would not have withstood the stresses imposed by travelling at the speed of sound, irrespective of the conjectural ‘popper’, a hypothetical soft tissue structure analogue to the terminal portion of a bullwhip able to surpass the speed of sound.

Conti, S., Tschopp E., Sala G., & Mateus O. (2021).  Multibody simulations of diplodocid tail motion. Annual conference of the European Association of Vertebrate Palaeontologists. , 5th-9th July : European Association of Vertebrate Palaeontologistsconti_et_al_2021_diplodocid_tail._eavp_abstract.pdf
Conti, S., Masarati P., Tschopp E., Zanoni A., Mateus O., & Sala G. (2023).  How to simulate soft tissues in extinct animals. Using sauropod dinosaurs as a case study. ECCOMAS Thematic Conference on Multibody Dynamics. Abstractconti_et_al_2023_id_218_424_eccomas_mbd_2023_congresso_lisbona.pdf

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Conti, S., Sala G., & Mateus O. (2023).  Smart Biomechanical Adaptation Revealed by the Structure of Ostrich Limb Bones. Biomimetics. 8(1), , Number 1 Abstractbiomimetics-08-00098.pdfWebsite

Ostriches are known to be the fastest bipedal animal alive; to accomplish such an achievement, their anatomy evolved to sustain the stresses imposed by running at such velocities. Ostriches represent an excellent case study due to the fact that their locomotor kinematics have been extensively studied for their running capabilities. The shape and structure of ostrich bones are also known to be optimized to sustain the stresses imposed by the body mass and accelerations to which the bones are subjected during movements. This study focuses on the limb bones, investigating the structure of the bones as well as the material properties, and how both the structure and material evolved to maximise the performance while minimising the stresses applied to the bones themselves. The femoral shaft is hollowed and it presents an imbricate structure of fused bone ridges connected to the walls of the marrow cavity, while the tibial shaft is subdivided into regions having different mechanical characteristics. These adaptations indicate the optimization of both the structure and the material to bear the stresses. The regionalization of the material highlighted by the mechanical tests represents the capability of the bone to adapt to external stimuli during the life of an individual, optimizing not only the structure of the bone but the material itself.

Coimbra, R., Moreno-Azanza M., Ezquerro L., Nuñez-Lahuerta C., Gasca J. M., Immenhauser A., Mateus O., & Rocha F. (2023).  Evaluating and comparing geochemical sampling protocols in dinosaur eggshells: refining Cretaceous ecosystem research. Cretaceous Research. 105632. Abstractsingle_file_coimbra_et_al._2023_cretresearch.pdfWebsite

The geochemical signatures of dinosaur eggshells represent well-established proxies in paleoenvironmental and paleobiological research. The variable sampling procedures reported in the literature, however, deserve attention. In order to evaluate the impact of different sampling methodologies on carbon and oxygen isotope and elemental concentrations, grinding was contrasted with drilling to extract powder samples from eggshell fragments collected at several locations. Eggshell data were further contrasted with surface materials, encasing matrix and compared with independent proxies using petrographic and elemental techniques. Iron and manganese elemental concentrations revealed an enrichment sequence depending on the sampling strategy for the same eggshell fragment. This pattern can be mistaken for a variable state of preservation. In contrast, carbon and oxygen isotope values exhibited only subtle differences and lacked clear trends. This suggests that isotope data are less susceptible to different methodological approaches. It is shown that drilling offers a wider range of possibilities compared to grinding (e.g., faster and less destructive). Additionally, drilled powder samples can confidently be used for elemental and isotope analysis, excluding contamination, thus providing a more accurate set of proxy data from eggshell archives.

Coelho,(ed)C., & et al (2013).  Arrábida - al-rábita. , Lisboa, 229 pp.: Associação de Município da Região de Setúbal
Clemmensen, L. B., Lindström S., Mateus O., Mau M., Milàn J., & Kent D. V. (2021).  A new vertebrate fossil-bearing layer in the Rhætelv Formation (Kap Stewart Group) of central East Greenland: evidence of a Hettangian marine incursion into the continental Jameson Land Basin. Lethaia. n/a, , Number n/a Abstractlet.12449.pdfWebsite

The Kap Stewart Group (Rhaetian-Sinemurian, Triassic–Early Jurassic) of the Jameson Land Basin in central East Greenland has traditionally been regarded as a strictly continental unit with delta and perennial lake sediments. New finds of plesiosaur bone remain in a thin storm deposited sandstone bed in the middle part of the Rhætelv Formation of the Kap Stewart Group, however, indicates a likely period of marine influence. At the study area at the eastern margin of the basin, the Rhætelv Formation is 300-m thick and overlies unconformably the Norian Fleming Fjord Group. The bone-bearing sandstone occurs 190 m above the base of the group and is closely associated with black laminated mudstones; palynological investigation of three samples from these mudstones indicates that they are of a younger Hettangian age. The Hettangian was a relatively short stage (201.3–199.5 Ma) and elsewhere characterized by two episodes of sea-level highstands. Assuming that the marine incursion in the Jameson land Basin evidenced by the plesiosaur fossil remains took place during the youngest of these sea-level highstands, the bone-bearing bed of the Rhætelv Formation can be dated to 200 Ma and thereby gives the first numerical age constraint of this hitherto poorly dated succession.

Clemmensen, L. B., Kent D. V., Mau M., Mateus O., & Milàn J. (2020).  Triassic lithostratigraphy of the Jameson Land basin (central East Greenland), with emphasis on the new Fleming Fjord Group. Bulletin of the Geological Society of Denmark. 68, 95–132. Abstractclemmensen_et_al_2020_triassic_lithostratigraphy_of_the_jameson_land_basin.pdfWebsite

The lithostratigraphy of the Triassic deposits of the Jameson Land Basin in central East Greenland is revised. The new Scoresby Land Supergroup is now composed of the Wordie Creek, Pingo Dal, Gipsdalen and Fleming Fjord Groups. This paper only deals with the lithostratigraphy of the late Early-Late Triassic continental deposits of the latter three groups with emphasis on the vertebratebearing Fleming Fjord Group. The new Pingo Dal Group consists of three new formations, the Rødstaken, Paradigmabjerg and Klitdal Formations (all elevated from members), the new Gipsdalen Group consists of three new formations, the Kolledalen, Solfaldsdal (with the new Gråklint Member) and Kap Seaforth Formations (all elevated from members), and the new Fleming Fjord Group is subdivided into three new formations, the Edderfugledal, Malmros Klint and Ørsted Dal Formations (all elevated from members). The Edderfugledal Formation contains two cyclic bedded, lacustrine members, a lowermost Sporfjeld Member (elevated from beds), and an uppermost Pingel Dal Member (elevated from beds). The lacustrine red beds of the Malmros Klint Formation are not subdivided. The lacustrine and fluvial Ørsted Dal Formation contains three new members. In the eastern and central part of the basin, the formation is initiated by cyclic bedded, red lacustrine mudstones of the Carlsberg Fjord Member (elevated from beds), while in the northwestern part of the basin the lowermost part of the formation is composed of grey fluvial conglomerates and sandstones with subordinate red mudstones of the Bjergkronerne Member (elevated from beds). The uppermost part of the formations in most of the basin is composed of cyclic bedded, variegated lacustrine mudstones and grey to yellowish marlstones of the Tait Bjerg Member (elevated from beds). The sediments in the Fleming Fjord Group contain remains of a rich and diverse vertebrate fauna including dinosaurs, amphibians, turtles, aeotosaurs, pterosaurs, phytosaurs and mammaliaforms. Most vertebrate bones have been found in uppermost Malmros Klint Formation, and in the Carlsberg Fjord and Tait Bjerg Members. The Norian–early Rhaetian, lacustrine Fleming Fjord Group was deposited at about 41° N on the northern part of the supercontinent Pangaea. Lacustrine sedimentation was controlled by seasonal as well as longer-term (orbital) variation in precipitation. Precipitation was probably brought to the basin by southwesterly winds. The lacustrine sediments of the uppermost Fleming Fjord Group show deposition during increasingly humid conditions changing the lake environment from an ephemeral lake-steppe area to a perennial lake. This evolution of lake environment suggests a change from a winter-wet temperate climate to one with precipitation throughout the year.

Clemmensen, L. B., Milàn J., Adolfssen J. S., Estrup E. J., Frobøse N., Klein N., Mateus O., & Wings O. (2015).  The vertebrate-bearing Late Triassic Fleming Fjord Formation of central East Greenland revisited: stratigraphy, palaeoclimate and new palaeontological data. Geological Society, London, Special Publications. 434(1), 31-47. Abstractclemmensenetal2015greenland.pdfWebsite

In Late Triassic (Norian–Rhaetian) times, the Jameson Land Basin lay at 40° N on the northern part of the supercontinent Pangaea. This position placed the basin in a transition zone between the relatively dry interior of the supercontinent and its more humid periphery. Sedimentation in the Jameson Land Basin took place in a lake–mudflat system and was controlled by orbitally forced variations in precipitation. Vertebrate fossils have consistently been found in these lake deposits (Fleming Fjord Formation), and include fishes, dinosaurs, amphibians, turtles, aetosaurs and pterosaurs. Furthermore, the fauna includes mammaliaform teeth and skeletal material. New vertebrate fossils were found during a joint vertebrate palaeontological and sedimentological expedition to Jameson Land in 2012. These new finds include phytosaurs, a second stem testudinatan specimen and new material of sauropodomorph dinosaurs, including osteologically immature individuals. Phytosaurs are a group of predators common in the Late Triassic, but previously unreported from Greenland. The finding includes well-preserved partial skeletons that show the occurrence of four individuals of three size classes. The new finds support a late Norian–early Rhaetian age for the Fleming Fjord Formation, and add new information on the palaeogeographical and palaeolatitudinal distribution of Late Triassic faunal provinces.

Clemmensen, L. B., Milàn J., Adolfssen J. S., Estrup E. J., Frobøse N., Klein N., Mateus O., & Wings O. (2015).  The vertebrate-bearing Late Triassic Fleming Fjord Formation of central East Greenland revisited: stratigraphy, palaeoclimate and new palaeontological data. Geological Society, London, Special Publications. 434, AbstractWebsite

In Late Triassic (Norian–Rhaetian) times, the Jameson Land Basin lay at 40° N on the northern part of the supercontinent Pangaea. This position placed the basin in a transition zone between the relatively dry interior of the supercontinent and its more humid periphery. Sedimentation in the Jameson Land Basin took place in a lake–mudflat system and was controlled by orbitally forced variations in precipitation. Vertebrate fossils have consistently been found in these lake deposits (Fleming Fjord Formation), and include fishes, dinosaurs, amphibians, turtles, aetosaurs and pterosaurs. Furthermore, the fauna includes mammaliaform teeth and skeletal material. New vertebrate fossils were found during a joint vertebrate palaeontological and sedimentological expedition to Jameson Land in 2012. These new finds include phytosaurs, a second stem testudinatan specimen and new material of sauropodomorph dinosaurs, including osteologically immature individuals. Phytosaurs are a group of predators common in the Late Triassic, but previously unreported from Greenland. The finding includes well-preserved partial skeletons that show the occurrence of four individuals of three size classes. The new finds support a late Norian–early Rhaetian age for the Fleming Fjord Formation, and add new information on the palaeogeographical and palaeolatitudinal distribution of Late Triassic faunal provinces.

Ceríaco, L. M. P., Gutiérrez E. E., Dubois A., Abdala C. S., Alqarni A. S., Adler K., et al. (2016).  Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences. Zootaxa. 4196(3), 435 - 445., 2016 AbstractWebsite
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Ceríaco, L. M. P., Gutiérrez E. E., Dubois A., Abdala C. S., Alqarni A. S., Adler K., et al. (2016).  Photography-based taxonomy is inadequate, unnecessary, and potentially harmful for biological sciences. Zootaxa. 4196, 435-445., Number 3 Abstract
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Cavadas, B., Mestrinho N., & Mateus O. (2018).  Jurassic race: a collaborative pedagogical activity between paleontologists, mathematics and science education teachers. XVI Annual Meeting of the European Association of Vertebrate Palaeontologists. 41., Caparica, Portugal June 26th-July 1st, 2018: Abstract book of the XVI Annual Meeting of the European Association of Vertebrate Palaeontologists, Caparica, Portugal June 26th-July 1st, 2018. Abstractcavadas_et_al_2018_eavp_abstract.pdf

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Castanhinha, R., Araújo R., & Mateus O. (2009).  Dinosaur eggshell and embryo localities in Lourinhã Formation, Late Jurassic, Portugal. Journal of Vertebrate Paleontology, 29(3): . 76A. Abstractcastanhinhaetal2009dinosaureggshellp.pdf

Four different localities from the Late Jurassic of Lourinhã formation with eggshells and embryos were studied: Paimogo (lower Amoreira-Porto Novo member), Peralta (Praia Azul member), Porto das barcas (Bombarral member) and Casal da Rôla (Amoreira-Porto Novo member). All but Casal da Rôla have embryonic material. Preliminary results show that eggshells from Paimogo correspond to obliquiprismatic morphotype (0.92mm thick), similar to those from Morrison Formation. Within Paimogo site a different type of eggshell was discovered, having a radial section of 153 μm with a mammilary layer measuring 65 μm. Porto das Barcas eggshells represent a discretispherulitic morphotype (1,23 mm thick).
This locality presents a nest 60-cm diameter containing many eggshells but an indeterminate number of eggs. Some embryonic bones were discovered between the eggshells including teeth and skull bones showing that the eggs belong to a saurischian, tentatively a sauropod dinosaur. Peralta nest eggshells are preliminary ascribed to obliquiprismatic morphotype (column: 0,56mm and mammilla: 0,21mm) probably related to Paimogo’s nest taxon (Lourinhanosaurus). Peralta site bears embryonic bones namely small theropod teeth associated with bone fragments, and unidentifiable dinosaur vertebra. Only eggshells have been collected at Casal da Rôla (ML1194). The eggshells (0,78mm thick) are prismatic morphotype and it was impossible to determine the pore system, the outer surface is smooth with no ornamentation.
Lourinhã formation has the oldest sauropod and theropod nest with embryos known so far.

Castanhinha, R., & Mateus O. (2006).  On the left-right asymmetry in dinosaurs. Journal of Vertebrate Paleontology, 26 (Suppl. To 3): 48A.. 26, 48–48., Number Suppl. to Abstract
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Castanhinha, R., Araujo R., & Mateus O. (2008).  Reptile Egg Sites From Lourinhã Formation, Late Jurassic, Portugal. Livro de Resumos de Tercer Congreso Latinoamericano de Paleontología de Vertebrados. , Neuquén, Argentina Abstract
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Castanhinha, R., Araujo R., & Mateus O. (2009).  Dinosaur eggshell and embryo localities in Lourinhã Formation, Late Jurassic, Portugal. Journal of Vertebrate Paleontology. 29, 76., Number 3 Abstract
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Castanhinha, R., & Mateus O. (2006).  On the left-right asymmetry in dinosaurs. Journal of Vertebrate Paleontology. 26(Suppl. To 3), 48A. Abstractcastanhinhamateus2006.pdf

The study of different kinds of morphological left-right (L-R) asymmetries in all taxa is a very powerful tool to understand evolution since it is a way to measure the developmentalstability of an organism against environmental perturbations. Excluding every pathologic or subtle asymmetry and all cases of taphonomic distortion, this work focuses only on two
kinds of unambiguous asymmetries: fluctuating and adaptative asymmetry. There are several cases of conspicuous left-right asymmetry in dinosaurs and is probably more common than previously thought. The pneumatic cavities systems in skull and vertebrae of theropodsand sauropods are the most common cases reported. The shape (but not the occurrence) of pneumatic cavities might have been exposed to weak selective pressure becoming more random than other body structures. Asymmetries are rarer in the appendicular bones possibly because it represents a strong handicap in the function of the limbs, consequently in the locomotion of the individual. Teeth counting show many exceptions to the typical L-R symmetry. Peculiar cases of adaptive asymmetry are related with the plates of stegosaurs and the ear displacement in the skull of the troodontids, which may have an important role in the physiology and ecology of the animals. The asymmetric displacement maximizes the surface exposure of the stegosaurs dorsal plates. This is an advantage, either the plates were used for thermoregulation, display or specific identification. Work in progress on the braincases of some troodontids specimens shows asymmetric ear openings, which suggests thatcan be an analogy resulting from convergent evolution between troodontids and strigiformes birds, used for 3D directional acoustics. Asymmetries are more common in animals that develop under stress. Animals that lived under dramatic environmental changes periods—like mass-extinctions episodes are believed to be—should present more asymmetries.
However, much more sampling and time accuracy is required in order to be able to relate dinosaur asymmetries to extinction episodes. Asymmetries show strong intra-individual variation and should be taken in consideration in taxonomical studies.

Castanhinha, R., Araujo R., & Mateus O. (2008).  Reptile Egg Sites From Lourinhã Formation, Late Jurassic, Portugal. Livro de Resumos de Tercer Congreso Latinoamericano de Paleontologia de Vertebrados. , Neuquén, Argentina Abstractcastanhinha_et_al_2008_reptile_egg_sites_from_lourinha_formation_late_jurassic_portugal.pdf

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Castanhinha, R., & Mateus O. (2007).  Short review on the marine reptiles of Portugal: ichthyosaurs, plesiosaurs and mosasaurs. Journal of Vertebrate Paleontology. 27(suppl. to 3), 57. Abstract
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Castanhinha, R., Araujo R., & Mateus O. (2009).  Dinosaur eggshell and embryo localities in Lourinhã Formation, Late Jurassic, Portugal. Journal of Vertebrate Paleontology. 29, 76–76., Number 3 Abstract
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Castanhinha, R., & Mateus O. (2006).  On the left-right asymmetry in dinosaurs. Journal of Vertebrate Paleontology, 26 (Suppl. To 3): 48A.. 26, 48., Number Suppl. to 3 Abstract
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Castanhinha, R., Araujo R., & Mateus O. (2008).  Reptile Egg Sites From Lourinhã Formation, Late Jurassic, Portugal. Livro de Resumos de Tercer Congreso Latinoamericano de Paleontología de Vertebrados. , Neuquén, Argentina Abstract
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Carrano, M., Mateus O., & Mitchell J. (2013).  First definitive association between embryonic Allosaurus bones and prismatoolithus eggs in the Morrison Formation (Upper Jurassic, Wyoming, USA). Annual Meeting of Vertebrate Paleontology. 101.: Journal of Vertebrate Paleontology, Program and Abstracts, 2013 Abstractcarrano_mateus_mitchell_2013_allosaurus_embryos_morrison_svp_abstract.pdf

Despite more than a century of collecting, resulting in one of the best-studied vertebrate fossil records anywhere in the world, the Upper Jurassic Morrison Formation has produced surprisingly few examples of dinosaur eggs associated with embryonic remains. Even more puzzling, none of these seem to pertain to the theropod Allosaurus, one of the most common and best-understood dinosaur taxa in the formation. Here we
report on a dinosaur nest site that has produced both abundant prismatoolithid eggshell and embryonic (or perinatal) bones of Allosaurus from Fox Mesa, Wyoming. This represents the first such discovery for any theropod in the Jurassic of North America. The nest is heavily weathered but contains a few ellipsoid eggshell clusters that suggest an egg size of about 8 x 6.5 cm. Study of the eggshell morphology and microstructure confirms that a single egg type is present throughout, which is indistinguishable from Prismatoolithus coloradensis. All of the identifiable embryonic materials pertain to theropods, and two premaxillae specimens show the five alveoli diagnostic for Allosaurus among Morrison theropods. This confirms the theropod origin of Prismatoolithus eggs and implicates Allosaurus as the specific Morrison parent taxon. As a result, it is now possible to assign several previous discoveries of dinosaur eggs and potential nests to Allosaurus, including the isolated egg from the Cleveland-Lloyd Quarry. This discovery
also calls into question prior assignments of Prismatoolithus eggs to ornithopods, and suggests that more detailed study of such sites is warranted. Prismatoolithus eggshells are also associated with the Upper Jurassic theropod Lourinhanosaurus from Portugal, along with larger embryos that exhibit four premaxillary alveoli.

Campos, H., Mateus O., & Moreno-Azanza M. (2017).  Preliminary results on the stratigraphy and taphonomy of multiple bonebeds in the Triassic of Algarve. Abstract book of the XV Encuentro de Jóvenes Investigadores en Paleontología/XV Encontro de Jovens Investigadores em Paleontologia, Lisboa, 428 pp.. 83-87. Abstractcampos_et_al._2017_preliminary_results_pn_the_stratigraphy_and_taphonomy_of_multiple_beds_in_the_triassic_of_algarve..pdf

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Campos, H., & Mateus O. (2018).  The first record of placodonts in Portugal and its chronological and paleoecological implications. XVI Annual Meeting of the European Association of Vertebrate Palaeontologists. 38.: Abstract book of the XVI Annual Meeting of the European Association of Vertebrate Palaeontologists, Caparica, Portugal June 26th-July 1st, 2018. Abstract

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Campos, H., & Mateus O. (2018).  The first record of placodonts in Portugal and its chronological and paleoecological implications. XVI Annual Meeting of the European Association of Vertebrate Palaeontologists. 38.: Abstract book of the XVI Annual Meeting of the European Association of Vertebrate Palaeontologists, Caparica, Portugal June 26th-July 1st, 2018. Abstractcampos__mateus_2018_eavp_abstract.pdf

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