14:56 19 May 2010 by Shanta Barley
This may mean that the structure of mammalian hair has remained unchanged for much of our evolution, says Romain Vullo at the University of Rennes I in France, who discovered the hair. "Perhaps mammalian hair does its job so well that it does not need to evolve."
Hairs in amber, just like ours (Image: V. Girard (Senckenberg Museum) & R. Vullo (Géosciences Rennes)
Imprints of fur have been seen in two 160-million-year-old fossils in China, but this is the oldest example of actual hair, and therefore the first time researchers have been able to study the pattern of scales on their surface.
It turns out that the pattern is identical to that found on modern mammalian hair: rows of overlapping scales stacked on top of each other in an orderly fashion, with each row roughly 2 to 8 micrometres high.
This discovery is "wonderful progress", says Zhe-Xi Luo, Curator of Vertebrate Paleontology at the Carnegie Museum of Natural History in Pittsburgh, Pennsylvania. "It shows the microstructure of hairs of mammals have always been the same."
Crime scene
Vullo discovered the amber-encased hair in the Font-de-Benon quarry in Charente-Maritime, south-western France. Around 100 million years ago, the site of what is now the quarry was a lush tropical forest.
Interpreting the ancient "crime scene" where the hair's owner died is fraught with difficulties.
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Read more here/Leia mais aqui: New Scientist
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Mammalian hairs in Early Cretaceous amber
Journal Naturwissenschaften
Publisher Springer Berlin / Heidelberg
ISSN 0028-1042 (Print) 1432-1904 (Online)
Category Short Communication
DOI 10.1007/s00114-010-0677-8
Subject Collection Biomedical and Life Sciences
SpringerLink Date Friday, May 14, 2010
Romain Vullo1 , Vincent Girard2 , Dany Azar3 and Didier Néraudeau1
(1) Université de Rennes 1, UMR CNRS 6118, Campus de Beaulieu, avenue du général Leclerc, 35042 Rennes, France
(2) Senckenberg Forschungsinstitut und Naturmuseum, Senckenberganlage 25, 60325 Frankfurt am Main, Germany
(3) Faculty of Sciences II, Department of Biology, Lebanese University, P.O. Box 26110217, Fanar-Matn, Lebanon
Received: 23 February 2010 Revised: 28 April 2010 Accepted: 29 April 2010 Published online: 14 May 2010
Communicated by R. Reisz
Abstract
Two mammalian hairs have been found in association with an empty puparium in a ∼100-million-year-old amber (Early Cretaceous) from France. Although hair is known to be an ancestral, ubiquitous feature in the crown Mammalia, the structure of Mesozoic hair has never been described. In contrast to fur and hair of some Jurassic and Cretaceous mammals preserved as carbonized filaments, the exceptional preservation of the fossils described here allows for the study of the cuticular structure. Results show the oldest direct evidence of hair with a modern scale pattern. This discovery implies that the morphology of hair cuticula may have remained unchanged throughout most of mammalian evolution. The association of these hairs with a possible fly puparium provides paleoecological information and indicates peculiar taphonomic conditions.
Keywords Mammal - Hair - Amber - Cretaceous - France
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NOTA IMPERTINENTE DESTE BLOGGER:
ESTASE, baby, ESTASE são dados (muito obrigado pela honestidade acadêmica Steven Jay Gould) muito importantes que não podem ser desconsiderados quando se examina o fato, Fato, FATO da evolução.
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