17:00 22 June 2010 by Jeff Hecht
The identification of an extremely well preserved 30-million-year old fossilised beak raises interesting questions over why evolution has left the birds so little changed over such a long period.
Just like its modern counterpart (Image: A. Louchart)
The nearly complete beak of the 30-million-year old fossil, found in the Luberon area of south-eastern France, resembles those of the seven modern pelican species so closely that it falls within the genus Pelecanus, says Antoine Louchart of the University of Lyon, France.
Pelican beaks are the longest of any living birds. Beneath the beak is a flexible pouch that allows the birds to capture their prey in the water, then spit out the water before swallowing their meal. Like other bird beaks, they are rarely preserved as fossils, so little had been known about their early evolution.
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Read more here/Leia mais aqui: New Scientist
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The earliest known pelican reveals 30 million years of evolutionary stasis in beak morphology
Journal Journal of Ornithology
Publisher Springer Berlin / Heidelberg
ISSN 0021-8375 (Print) 1439-0361 (Online)
Category Original Article
DOI 10.1007/s10336-010-0537-5
Subject Collection Biomedical and Life Sciences
SpringerLink Date Friday, May 28, 2010
Antoine Louchart1 , Nicolas Tourment2 and Julie Carrier3
(1) Institut de Génomique Fonctionnelle de Lyon, équipe “Evo-dévo de la denture chez les Vertébrés”, Ecole Normale Supérieure de Lyon, Université de Lyon, Université Lyon 1, CNRS, INRA, 46 Allée d’Italie, 69364 Lyon cedex 07, France
(2) Nicolas Tourment, 9 Boulevard Ambroise Robert, 13012 Marseille, France
(3) Collège le Bassenon, rue Girard Desargues, 69420 Condrieu, France
Received: 7 August 2009 Revised: 12 March 2010 Accepted: 11 May 2010 Published online: 29 May 2010
Communicated by F. Bairlein.
Abstract
The feeding apparatus of Paleogene birds is rarely well-preserved. Here, we describe the earliest known pelican (early Oligocene, Luberon, southeastern France), with its almost complete beak. Morphologically identical to modern pelicans, the new fossil already shows several advanced features unique to extant species of the genus Pelecanus. It probably belongs to the lineage ancestral to all or some of these pelican species. This fossil reveals a remarkable evolutionary stasis in the morphology of such an advanced avian feeding apparatus through ca. 30 million years. Several hypotheses are proposed to suggest explanations for such examples of long stases in volant homeothermic vertebrates.
Keywords Cranial kinesis - Evolution - Feeding apparatus - Oligocene - Pelecanus
Antoine Louchart
Email: antoine.louchart@ens-lyon.fr
Email: a222313c@yahoo.fr
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NOTA CAUSTICANTE DESTE BLOGGER:
Gente, são 30 milhões de anos de estase. O pelicano continuou sendo pelicano. O registro fóssil, que Darwin disse ser incompleto (para blindar sua teoria das críticas mesmo científicas), desde 1859 teima em não corroborar a maior ideia que toda a humanidade já teve no contexto de justificação teórica.
Darwin pelo menos foi honesto em dizer que isso era um argumento grave contra sua teoria, mas hoje, em pleno século 21, com muito mais recursos tecnológicos e grana para pesquisas, a Nomenklatura científica é ranheta e finca os pés, estulta como mula que empaca, mas não reconhece que isso é um argumento muito forte contra o fato, Fato, FATO da evolução.
E a questão de estase sequer é abordada nos livros de Biologia do ensino médio aprovados pelo MEC/SEMTEC/PNLEM e o que isso significa para o estabelecimento do fato, Fato, FATO da evolução. Chamam isso de ciência. Eu chamo de alquimia e de 171 epistêmico...
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