quinta-feira, dezembro 18, 2008

Pegadas da Lourinhã sugerem maior flexibilidade de dinossauros saurópodes

O estudo hoje apresentado por mim e pelo colega Jesper Milàn da Universidade de Copenhaga, na Dinamarca, sugere, a partir de pegadas de dinossauros saurópodes da Lourinhã, que estes dinossauros tinham maior flexibilidade dos membros anteriores (braços) do que se pensava.

Os resultados são apresentados no congresso 52th Paleontological Association Annual Meeting que decorre de 18 a 21 de Dezembro de 2008 em Glasgow, Escócia.

Título: Sauropod forelimb flexibility deduced from deep manus tracks
Resumo em inglês:
  Sauropods are often considered to have very limited mobility and reduced limb flexibility, mainly due to their giant size and consequent weight. 
        In Lourinhã Formation, in central west Portugal, deep vertical natural cast of manus tracks are often preserved as the infills of the original track (see an example in Milàn et al., 2005). This manus tracks are vertical walled, with marks of the striations of the skin scales, showing that the movement of the sauropod manus into the mud is totally vertical with no horizontal component of the stride movement. Some track are up to 66 cm deep, which is equivalent to the height of whole manus, and means that sauropods could lift the anterior feet in a complete vertical manner. Such movement is only possible if there is a mobility at elbow and shoulder articulations in a higher degree that previously thought for sauropods. Our vision of sauropod limbs as inflexible columns has to be updated to more dynamic limbs and body.

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