Abstract
Restricted accessMoreSectionsView PDF ToolsAdd to favoritesDownload CitationsTrack Citations ShareShare onFacebookTwitterLinked InRedditEmail Cite this article Woodbury C. Jeffery 1998Two spinal cords in birds: novel insights into early avian evolutionProc. R. Soc. Lond. B.2651721–1729http://doi.org/10.1098/rspb.1998.0494SectionRestricted accessTwo spinal cords in birds: novel insights into early avian evolution C. Jeffery Woodbury C. Jeffery Woodbury Department of Ornithology, American Museum of Natural History, 79th Street and Central ParkWest, NewYork, New York 10024, USA [email protected] Google Scholar Find this author on PubMed Search for more papers by this author C. Jeffery Woodbury C. Jeffery Woodbury Department of Ornithology, American Museum of Natural History, 79th Street and Central ParkWest, NewYork, New York 10024, USA [email protected] Google Scholar Find this author on PubMed Search for more papers by this author Published:22 September 1998https://doi.org/10.1098/rspb.1998.0494AbstractBirds can be subdivided into two large superordinal assemblages based on differences in the dorsal horn of the spinal grey matter. Palaeognaths (i.e. ratites and tinamous), along with a few other orders of neognathous birds, exhibit the primitive dorsal horn state characteristic of other amniotes wherein cutaneous nerves form a single map of the body surface across the dorsal horn. In contrast, the vast majority of neognaths exhibit a novel, distinctly bifid dorsal horn wherein cutaneous nerves form not one, but two separate maps of the skin, each lying side–by–side. This unusual dorsal horn organization, which has been highly conserved and represents the derived state in birds, may identify a novel, major avian clade. These findings shed new light on historically problematic taxa and the early evolutionary branching sequence among living birds. Most notably, they reveal that the traditional orders Gruiformes, Columbiformes, Cuculiformes and Piciformes are unnatural assemblages. Further, in addition to palaeognaths, these findings suggest that most gruiforms, including buttonquails and mesites, as well as pigeons, cuckoos, woodpeckers and songbirds, represent ancient lineages whose ancestry predates the majority of ‘modern’ birds. The phylogeny of living birds may thus be likened more to a dense bush than the traditional tree, with more than half of all living species arising from a basal side branch. Previous ArticleNext Article VIEW FULL TEXT DOWNLOAD PDF FiguresRelatedReferencesDetailsCited by Wild J (2015) The Avian Somatosensory System Sturkie's Avian Physiology, 10.1016/B978-0-12-407160-5.00005-1, (55-69), . Livezey B (2009) Phylogenetics of Modern Shorebirds (Charadriiformes) Based on phenotypic Evidence: I—Characterization, Bulletin of Carnegie Museum of Natural History, 10.2992/013.040.0101, 40, (1-96), Online publication date: 1-Dec-2009. Evrard H (2006) Estrogen synthesis in the spinal dorsal horn: a new central mechanism for the hormonal regulation of pain, American Journal of Physiology-Regulatory, Integrative and Comparative Physiology, 10.1152/ajpregu.00930.2005, 291:2, (R291-R299), Online publication date: 1-Aug-2006. LIVEZEY and ZUSI (2006) PHYLOGENY OF NEORNITHES, Bulletin of Carnegie Museum of Natural History, 10.2992/0145-9058(2006)37[1:PON]2.0.CO;2, 37, (1-544), Online publication date: 1-Jun-2006. Posso S and Donatelli R (2006) Análise filogenética e implicações sistemáticas e evolutivas nos Cuculiformes (Aves) com base na osteologia, comportamento e ecologia, Revista Brasileira de Zoologia, 10.1590/S0101-81752006000300003, 23:3, (608-629), Online publication date: 1-Sep-2006. Mayr G and Clarke J (2005) The deep divergences of neornithine birds: a phylogenetic analysis of morphological characters, Cladistics, 10.1111/j.1096-0031.2003.tb00387.x, 19:6, (527-553), Online publication date: 1-Dec-2003. Woodbury C, Ritter A and Koerber H (2001) Central anatomy of individual rapidly adapting low-threshold mechanoreceptors innervating the ?hairy? skin of newborn mice: Early maturation of hair follicle afferents, The Journal of Comparative Neurology, 10.1002/cne.1069, 436:3, (304-323), Online publication date: 30-Jul-2001. Woodbury C, Ritter A and Koerber H (2000) On the problem of lamination in the superficial dorsal horn of mammals: A reappraisal of the substantia gelatinosa in postnatal life, The Journal of Comparative Neurology, 10.1002/(SICI)1096-9861(20000131)417:1<88::AID-CNE7>3.0.CO;2-U, 417:1, (88-102), Online publication date: 31-Jan-2000. Homberger D and de Silva K (2000) Functional Microanatomy of the Feather-Bearing Integument: Implications for the Evolution of Birds and Avian Flight, American Zoologist, 10.1093/icb/40.4.553, 40:4, (553-574), Online publication date: 1-Aug-2000. Homberger D and de Silva K (2000) Functional Microanatomy of the Feather-Bearing Integument: Implications for the Evolution of Birds and Avian Flight1, American Zoologist, 10.1668/0003-1569(2000)040[0553:FMOTFB]2.0.CO;2, 40:4, (553-574), Online publication date: 1-Aug-2000. Tuinen M, Sibley C and Hedges S (2000) The Early History of Modern Birds Inferred from DNA Sequences of Nuclear and Mitochondrial Ribosomal Genes, Molecular Biology and Evolution, 10.1093/oxfordjournals.molbev.a026324, 17:3, (451-457), Online publication date: 1-Mar-2000. Dubbeldam J (2008) The Sensory Trigeminal System in Birds: Input, Organization and Effects of Peripheral Damage. A Review, Archives of Physiology and Biochemistry, 10.1076/apab.106.5.338.4367, 106:5, (338-345), Online publication date: 1-Jan-1998. This Issue22 September 1998Volume 265Issue 1407 Article InformationDOI:https://doi.org/10.1098/rspb.1998.0494Published by:Royal SocietyPrint ISSN:0962-8452Online ISSN:1471-2954History: Published online22/09/1998Published in print22/09/1998 License: Citations and impact Keywordsspinal cordsystematicsphylogenydorsal hornevolutionbirds Large datasets are available through Proceedings B's partnership with Dryad
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
More From: Proceedings of the Royal Society of London. Series B: Biological Sciences
Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.