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Using a Thermal Camera to Measure Heat Loss Through Bird Feather Coats
Published on: June 17, 2020
Spina cortica and Tapetum spinosus, two new microstructures of flight feathers: description, function and
L C Straker1, M A Raposo, Márcia Attias
1Setor de Ornitologia, Departamento de Vertebrados, Museu Nacional/UFRJ, Quinta da Boa Vista, São Cristóvão, 20940-040 Rio de Janeiro, Brazil. locobra@biologia.ufrj.br
Abstract:
The importance of feathers for the avian group has made them one of the most studied epidermal structures both from the morphological and evolutionary point of view. Surprisingly, our observations by Scanning Electron Microscopy detected the presence of two structures widely distributed within different avian groups and not yet described. In this paper we describe these two new structures (Spina cortica and Tapetum spinosus) and map their distribution within modern birds. The S. cortica is a thorn-like microstructure that grows on the barb cortex and the T. spinosus is the assemblage of these thorns. The distribution of these new structures among birds and their morphological diversity could be of great interest to taxonomists and evolutionary biologists interested in the origin of bird flight.
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