Capacidade de vôo do Archaeopteryx e Confuciusornis questionada

Science 14 May 2010:
Vol. 328. no. 5980, pp. 887 - 889
DOI: 10.1126/science.1188895

Narrow Primary Feather Rachises in Confuciusornis and Archaeopteryx Suggest Poor Flight Ability

Robert L. Nudds1,* and Gareth J. Dyke2

Archaeopteryx

The fossil birds Archaeopteryx and Confuciusornis had feathered wings resembling those of living birds, but their flight capabilities remain uncertain. Analysis of the rachises of their primary feathers shows that the rachises were much thinner and weaker than those of modern birds, and thus the birds were not capable of flight. Only if the primary feather rachises were solid in cross-section (the strongest structural configuration), and not hollow as in living birds, would flight have been possible. Hence, if Archaeopteryx and Confuciusornis were flapping flyers, they must have had a feather structure that was fundamentally different from that of living birds. Alternatively, if they were only gliders, then the flapping wing stroke must have appeared after the divergence of Confuciusornis, likely within the enantiornithine or ornithurine radiations.

 Confuciusornis

1 Faculty of Life Sciences, University of Manchester, Manchester M13 9PT, UK.
2 School of Biology and Environmental Science, University College Dublin, Belfield 4, Dublin, Ireland.

* To whom correspondence should be addressed. E-mail: robert.nudds@manchester.ac.uk

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Images/Imagens: Historum

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NOTA CAUSTICANTE DESTE BLOGGER:

As evidências encontradas na natureza de que um dinossauro se transformou em tico-tico não são assim uma Brastemp de robustez epistêmica no contexto de justificação teórica. Ah, não custa nada imaginar como que  esse processo evolutivo escama-pena ocorreu ao longo de milhões de anos através de mutações sendo aleatoriamente filtradas pela seleção natural, e outros mecanismos evolutivos de A a Z, pois afinal de contas, a evolução é mais inteligente do que você idiota!

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