The rectrix and remex seen above are two examples of pennaceous feathers.
An ostrich down feather is an example of a plumulaceous feather. Its rudimentary rhachis with long flexible barbs and elongate barbules cannot form vanes.
Descriptionedit
A pennaceous feather has a stalk or quill.[2] Its basal part, called a calamus, is embedded in the skin. The calamus is hollow and has pith formed from the dry remains of the feather pulp, and the calamus opens below by an inferior umbilicus and above by a superior umbilicus.[2] The stalk above the calamus is a solid rachis having an umbilical groove on its underside. Pennaceous feathers have a rachis with vanes or vaxillum spreading to either side. These vanes are composed of a high number of flattened barbs, that are connected to one another with barbules.
The barbules are tiny strands that criss-cross on the flattened sides of the barbs. This forms a miniature velcro-like mesh that holds all the barbs together, stabilizing the vanes.[3]
Pennaceous feathers on the wing, and elsewhere that stresses related to flight or other activities are high, are accordingly attached especially strongly. This strong attachment is accomplished by ligaments under the skin, which in some birds and other feathered dinosaurs results in raised bumps or marks along the rear forelimb bone (ulna). These bumps, called quill knobs (ulnar papillae), are often used as an indirect indication of strongly-attached forelimb feathers in fossil species, and can also indirectly indicate the number of secondary remiges in a given specimen.[4][5]
^. www.geol.umd.edu. Archived from the original on 2017-03-17. Retrieved 2015-06-01.
^ ab. people.eku.edu. Archived from the original on 2017-02-25. Retrieved 2015-06-01.
^A Kovalev, AE Filippov, SN Gorb (2014) Unzipping bird feathers. J. R. Soc. Interface 11 (92) 20130988. doi:10.1098/rsif.2013.0988
^Turner, A.H.; Makovicky, P.J.; Norell, M.A. (2007). "Feather quill knobs in the dinosaur Velociraptor". Science. 317 (5845): 1721. Bibcode:2007Sci...317.1721T. doi:10.1126/science.1145076. PMID 17885130.
^Zelenitsky, D. K.; Therrien, F.; Erickson, G. M.; Debuhr, C. L.; Kobayashi, Y.; Eberth, D. A.; Hadfield, F. (2012). "Feathered Non-Avian Dinosaurs from North America Provide Insight into Wing Origins". Science. 338 (6106): 510–514. Bibcode:2012Sci...338..510Z. doi:10.1126/science.1225376. PMID 23112330. S2CID 2057698.
This article about ornithology is a stub. You can help Wikipedia by expanding it.
pennaceous, feather, pennaceous, feather, type, feather, present, most, modern, birds, some, other, species, maniraptoriform, dinosaurs, rectrix, remex, seen, above, examples, pennaceous, feathers, ostrich, down, feather, example, plumulaceous, feather, rudime. The pennaceous feather is a type of feather present in most modern birds and in some other species of maniraptoriform dinosaurs 1 The rectrix and remex seen above are two examples of pennaceous feathers An ostrich down feather is an example of a plumulaceous feather Its rudimentary rhachis with long flexible barbs and elongate barbules cannot form vanes Description editA pennaceous feather has a stalk or quill 2 Its basal part called a calamus is embedded in the skin The calamus is hollow and has pith formed from the dry remains of the feather pulp and the calamus opens below by an inferior umbilicus and above by a superior umbilicus 2 The stalk above the calamus is a solid rachis having an umbilical groove on its underside Pennaceous feathers have a rachis with vanes or vaxillum spreading to either side These vanes are composed of a high number of flattened barbs that are connected to one another with barbules The barbules are tiny strands that criss cross on the flattened sides of the barbs This forms a miniature velcro like mesh that holds all the barbs together stabilizing the vanes 3 Pennaceous feathers on the wing and elsewhere that stresses related to flight or other activities are high are accordingly attached especially strongly This strong attachment is accomplished by ligaments under the skin which in some birds and other feathered dinosaurs results in raised bumps or marks along the rear forelimb bone ulna These bumps called quill knobs ulnar papillae are often used as an indirect indication of strongly attached forelimb feathers in fossil species and can also indirectly indicate the number of secondary remiges in a given specimen 4 5 Flight feathers remiges and rectrices are specialized types of pennaceous feathers adapted for high loadings and often strongly asymmetric for improved flight performance See also editPin featherReferences edit GEOL 204 The Fossil Record Feathered Dragons The Origins of Birds and of Avian Flight www geol umd edu Archived from the original on 2017 03 17 Retrieved 2015 06 01 a b Feather evolution people eku edu Archived from the original on 2017 02 25 Retrieved 2015 06 01 A Kovalev AE Filippov SN Gorb 2014 Unzipping bird feathers J R Soc Interface 11 92 20130988 doi 10 1098 rsif 2013 0988 Turner A H Makovicky P J Norell M A 2007 Feather quill knobs in the dinosaur Velociraptor Science 317 5845 1721 Bibcode 2007Sci 317 1721T doi 10 1126 science 1145076 PMID 17885130 Zelenitsky D K Therrien F Erickson G M Debuhr C L Kobayashi Y Eberth D A Hadfield F 2012 Feathered Non Avian Dinosaurs from North America Provide Insight into Wing Origins Science 338 6106 510 514 Bibcode 2012Sci 338 510Z doi 10 1126 science 1225376 PMID 23112330 S2CID 2057698 nbsp This article about ornithology is a stub You can help Wikipedia by expanding it vte Retrieved from https en wikipedia org w index php title Pennaceous feather amp oldid 1187524688, wikipedia, wiki, book, books, library,
