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2006
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., & 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., & 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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2005
Milan, J., Christiansen P., & Mateus O. (2005).  A three-dimensionally preserved sauropod manus impression from the Upper Jurassic of Portugal: Implications for sauropod manus shape and locomotor mechanics. Kaupia. 14, 47-52. Abstractmilan_et_al_mateus_2005_-_3d_sauropod_manus_track_l_j_portugal.pdfWebsite

Sauropods were the largest animals ever to walk the earth, and evolved several specializations in their limbs in order to support their body mass. Their legs became columnar and their manual digits became reduced and encapsulated in tissue to form a single weight-bearing unit in the derived sauropods. A new three-dimensionally preserved cast of a sauropod manus, found in the Upper Jurassic Lourinhã Formation, Portugal, demonstrates not only the shape, but also the actual movements of the sauropod manus during the stride. The manus cast is 32 cm deep, and show the manus to be hoof-shaped and lacking any impressions of individual digits, except for digit I, the pollex. Well preserved striations from skin on the sides of the cast show that the manus was covered in rough, tubercular skin. The width of the manus cast is consistent from top to bottom, demonstrating that the manus was brought down and lifted vertically before any parasaggital movement of the upper limb took place.

2004
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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1999
Mateus, O. (1999).  Monofilia dos dinossauros e Origem das Aves: Serão as aves dinossauros?. (P, P Catry, F Moreira, Ed.).Actas do II Congresso de Ornitologia. 184-185., Lisboa: SPEA- Sociedade Portuguesa para o Estudo das Aves Abstract
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Mateus, O. (1999).  Monofilia dos dinossauros e Origem das Aves: Serão as aves dinossauros?. (Spea- Sociedade Portuguesa para o Estudo das Aves, P, P Catry, F Moreira, Ed.).Actas do II Congresso de Ornitologia. 184-185., Lisboa Abstract
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