Darwin, sinto muito, mas o olho continua dizendo um sonoro NÃO às suas especulações transformistas: num abrir e fechar de olhos!

quarta-feira, junho 29, 2011

Modern optics in exceptionally preserved eyes of Early Cambrian arthropods from Australia 

Michael S. Y. Lee, James B. Jago, Diego C. García-Bellido, Gregory D. Edgecombe, James G. Gehling & John R. Paterson

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Nature 474, 631–634 (30 June 2011) doi:10.1038/nature10097
Received 06 February 2011 
Accepted 01 April 2011 
Published online 29 June 2011


Despite the status of the eye as an “organ of extreme perfection”1, theory suggests that complex eyes can evolve very rapidly2. The fossil record has, until now, been inadequate in providing insight into the early evolution of eyes during the initial radiation of many animal groups known as the Cambrian explosion. This is surprising because Cambrian Burgess-Shale-type deposits are replete with exquisitely preserved animals, especially arthropods, that possess eyes3, 4, 5. However, with the exception of biomineralized trilobite eyes, virtually nothing is known about the details of their optical design. Here we report exceptionally preserved fossil eyes from the Early Cambrian (~515 million years ago) Emu Bay Shale of South Australia, revealing that some of the earliest arthropods possessed highly advanced compound eyes, each with over 3,000 large ommatidial lenses and a specialized ‘bright zone’. These are the oldest non-biomineralized eyes known in such detail, with preservation quality exceeding that found in the Burgess Shale and Chengjiang deposits. Non-biomineralized eyes of similar complexity are otherwise unknown until about 85 million years later6, 7. The arrangement and size of the lenses indicate that these eyes belonged to an active predator that was capable of seeing in low light. The eyes are more complex than those known from contemporaneous trilobites and are as advanced as those of many living forms. They provide further evidence that the Cambrian explosion involved rapid innovation in fine-scale anatomy as well as gross morphology, and are consistent with the concept that the development of advanced vision helped to drive this great evolutionary event8.

Subject terms: Evolution, Palaeontology, Geology and geophysics, Organismal biology

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NOTA DESTE BLOGGER:

Darwin escreveu certa vez que sentia calafrios só de pensar na complexidade do olho. Meu amigo Darwin, os olhos continuam dando calafrios em você? Dê uma olhada neste artigo e veja que suas especulações transformistas não são corroboradas no contexto de justificação teórica (as evidências) desde 1859...

Fui, nem sei por que, pensando será que a Nomenklatura científica é tão cega que não consegue ver que a teoria da evolução de Darwin acertou no varejo e errou no atacado???