DOCSLIB.ORG

Part Process Entailing Loss of Old Feathers

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Part Process Entailing Loss of Old Feathers THE MECHANISM OF FEATHER REPLACEMENT DURING NATURAL MOLT G•oxG• E. WATSON MOST ornithological reference books state that natural molt is a two- part processentailing loss of old feathers, "ecdysis," and subsequent growth of new feathers, "endysis" (Stresemann,1927; Mayaud, 1950; Wing, 1956; Van Tyne and Berger, 1959). Furthermore, investigators who have studiedmolt in penguins,cassowaries, and emusstate or imply that they are aberrant,since, in thesebirds, the old feathersare pushed out attachedto the tips of the feathersof the incominggeneration and are later abradedor are pulled off by the bird (Bartlett, 1879; Lowe, 1933; Friedmann, 1949; Rand, 1950). The evidenceto be presentedin this paper,very briefly reportedearlier by Watson (1963), indicates,however, that this latter mechanismof feather replacementis more widespread among birds than previouslybelieved and that natural molt is actively concernedonly with the incominggeneration. This finding is of signifi- cancefor relating molts to plumages,especially in view of the current con- troversy over their nomenclature(Humphrey and Parkes, 1959, 1963; Miller, 1961, 1962; Stresemann,1963). During the courseof early developmentin birds, the natal downsare carried out on the tips of the incomingjuvenal feathersin the first molt, but are soonabraded. For this reason,some authors have maintained that down should not be considereda separate generation,but merely the modifiedtips of the juvenal feathers (Jones,1907). Furthermore,pluck- ing a definitive feather usually stimulatesregeneration (Lillie and Juhn, 1932; but see Morton, 1962). The distal portion of the papilla is torn away in plucking but the papilla beginshealing over at once and usually an entire new feather is grown (Cohen and 'Espinasse,1961). The regen- eration of plucked feathershas receivedmuch attention, especiallyfrom developmentalbiologists interested in regulation and morphogenesis(see review by Lillie, 1942). Their findingshave been interpreted to reinforce the view that lossof feathersin molt stimulatesgrowth of the new feath- ers. The mechanismof replacementof feathersduring natural molt, how- ever, has been little investigated. MATERIALS AND METHODS Observationson molt in living birds were made on 6 hand-reared Rhode Island red chickens,20 Chukar Partridges (Al½½tori$½hukar), and 20 JapaneseQuail •a•oni½•). Most of these were incubator-hatched, but 7 chukars and $ quail were incubated by a domestic hen. The birds were kept in wire cagesand fed commercial chick starter (protein 25 per cent) supplementedwith fresh lettuce or grass; dry soil and eggshellswere available for dusting and grit. Until the birds were able to ther- tooregulate, they were brooded under a 100-watt incandescent bulb. Many of the 486 The Auk, 80: 456-495. October, Oct.1963 I W^rso>;,Feather Replacement 487 birds were handled daily and examinedfor molt while they were developing.All juvenal feathersdropped by one chukar were collectedevery other day. Nonliving material consistedof five birds. An adult male Chukar Partridge, which died while molting at the Highland Park Zoo in Pittsburgh, and an adult male House Sparrow (Passerdomesticus), picked up dead in Arlington, Virginia, were examined in the flesh. Flat skins of two molting Greater Scaup ducks (Aythya marila) were examinedimmediately after preparation. A wild Ruddy Sheld-Duck (Casarca ferrugi- nea), preservedin formalin in 1960, was studiedtwo years later. Molting feathers were examined and photographed,when possible,on the living bird. Others were plucked, and examinedor dissectedwhile fresh, under a binocular dissectingmicroscope. A few molting featherswere preservedin Bouin's or Carnoy's fluids and examined after fixation. In order to investigategrowth rate during the developmentof early feather gener- ations,Richard J. Hart, a studentat Yale University, made daily measurementsunder my direction on the innermostprimary (number I) in female "Hall Cross" Rhode Island red preservedembryos and living chicks. For each day of incubation (days II through 20) he measuredat least five specimens.Five chickswere raised for 32 days under the same conditions as the other live birds under observation. Measurements taken with caliperson the visible portion of the feather were recordedto the nearest 0.I mm in the embryos and 0.5 mm in the live chicks. ACKnOWLEDGMEnTS Most of the observationshere reported were made at the Peabody Museum of Nat- ural History while I was a resident graduate student in the Department of Zoology, Yale University. I thank S. D. Ripley, director of the museum, for providing me with space and cages; and E. J. Boell, chairman, for use of departmental incubator facilities and cagingmaterials. Among many personswho have contributed variously to this study, I am indebted to R. J. Andrew, A. Brewerton, J. Cohen, Mrs. Judith Lenz, L. L. Wolf, Mrs. Caroline Lutz, K. C. Parkes, P. Stettenheim, E. Stresemann, M. B. Trautman, J.P. Trinkaus, J. Weston, and my family. I am especiallygrateful to R. J. Hart for measuring chicks and to P. S. Humphrey for constructive criticism of the manuscript. OBSeRVAtiOnS A•D A Rhode Island red chick in its fifth week provided the first evidence that the two-step sequenceof molt might not be a reality. The bird had fully grown the inner juvenal primarieson both wings, but someof the more distal remigeswere still in growth. Becausethe primarieswere to be saved for work on pigmentation,they were pulled. When the innermost primary was plucked,the break camewell below the inferior umbilicusat the collar, that part of the papilla in which new growth was taking place. Firmly attached to the base of the calamusof the old feather was 10 mm of new feather sheath. The featherwas not easy to dislodgeand the force applied was considerable. The calamusof the juvenal primary is entirely keratinizedand contains a seriesof dry pulp caps. The outer wall of the new feather sheath ap- pears to be continuouswith the keratinized calamusof the old feather and 488 WATSO.%Feather Replacement [ Vol.Auk 80 there is no apparent constrictionat their juncture (Figure IA). Within the new sheath,barbs have begunto form but the vascularizedpulp still reachesalmost to the calamusof the old feather. The pulp capshave not dosed the inferior umbilicusas they do in later feathergenerations (Lil- Figure 1. A. Zone of juncture between base of calamus (light area) of juvena! innermost primary and tip of sheath (dark area) of first basic primary in five-week- old Rhode Island red chick. Total length of preservedspecimen, 18 mm. B. Juvenal flank feather (arrow) of living Chukar Partridge pushed out of follicle still attached to tip of incoming basic feather sheath. Other basic feathersalready breaking sheaths. Photographer'sfingers at bottom and left. C. Shed breast feather of adult Ruddy Sheld-Duck with broken-off cap of keratinized new feather sheath attached to base of calamus. lie, 1940). The new sheathhas not yet becomefully keratinizedand hard, even near its tip. Every molting bird subsequentlyinvestigated in detail has shown this samemode of feather replacementin all molts and in most feather tracts. The new feather sheath may push the base of the calamusof the old feather well beyond the end of the follicle so that the point of attachment of the two feather generationsis visible externally (Figure lB). Often there is a constrictionat the zone of juncture betweenthe two generations, but the outer layers of the calamusand sheathappear continuous.In the OCt.1963 ] WATSON,Feather Replacement 489 live bird, the calamusof the old featheris translucentand whitishbut the vascularizedpulp and barbsof the incomingfeather make the new sheath appeardull, dark purple. When the old feather,thus carriedout on the tip of the sheathof the incomingfeather, breaks off, part of the keratinizedtip of the newsheath comesaway attachedto the inferior umbilicusof the old feather (Figure 1C). This may help the sheathof the new feather to start breakingopen. Most of the attachedfeathers were foundduring the first prebasicmolt, but attachedfeathers were also presentin later molts. This phenomenon was observedin the hackles,wing coverts,and alulae of Rhode Island red cockerelsundergoing the subsequentmolt whenmore than six monthsold. A year-old Chukar Partridgeand an adult House Sparrowexamined soon after death showed several first basic feathers which had been carried out on the tips of sheathsduring the secondprebasic molt. Observationsby Dr. Milton B. Trautman (letter), on a captiveMottled Duck (Anas fulvigula) in 1953 suggestthat the sameprocess takes place in the wing quillsof year-oldducks: On June 18 at 11 a.m. "Fulvi" lost his first primary. That primary and all his other flight feathers were still firmly attached at 9 o'clock that same morning when I carefully jerked at some of the primaries. By 1 p.m. the next day (i.e. within 26 hours) he had lost all flight feathers. By early morning of the 19th, less than 24 hours after the first primary was dropped, some of the new primaries were one quarter inch out of the follicles.... When a feather was dropped, I could see the tip of the sheath of the new feather in the follicle. Definitive breast featherswere also found attachedto the tips of in- comingfeather sheaths in preservedflat skinsof wild Greater Scaupducks and in a wholespecimen of RuddySheld-Duck preserved in formalin.The connectionsbetween the two feather generationsin the skinsof the scaup had survivedmanual washingin detergentand benzeneand subsequent drying in sawdustand a forcedair stream.
Load more

Recommended publications
  • Dieter Thomas Tietze Editor How They Arise, Modify and Vanish
    Fascinating Life Sciences Dieter Thomas Tietze Editor Bird Species How They Arise, Modify and Vanish Fascinating Life Sciences This interdisciplinary series brings together the most essential and captivating topics in the life sciences. They range from the plant sciences to zoology, from the microbiome to macrobiome, and from basic biology to biotechnology. The series not only highlights fascinating research; it also discusses major challenges associated with the life sciences and related disciplines and outlines future research directions. Individual volumes provide in-depth information, are richly illustrated with photographs, illustrations, and maps, and feature suggestions for further reading or glossaries where appropriate. Interested researchers in all areas of the life sciences, as well as biology enthusiasts, will find the series’ interdisciplinary focus and highly readable volumes especially appealing. More information about this series at http://www.springer.com/series/15408 Dieter Thomas Tietze Editor Bird Species How They Arise, Modify and Vanish Editor Dieter Thomas Tietze Natural History Museum Basel Basel, Switzerland ISSN 2509-6745 ISSN 2509-6753 (electronic) Fascinating Life Sciences ISBN 978-3-319-91688-0 ISBN 978-3-319-91689-7 (eBook) https://doi.org/10.1007/978-3-319-91689-7 Library of Congress Control Number: 2018948152 © The Editor(s) (if applicable) and The Author(s) 2018. This book is an open access publication. Open Access This book is licensed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons license and indicate if changes were made.
    [Show full text]
  • Baker2009chap58.Pdf
    Ratites and tinamous (Paleognathae) Allan J. Baker a,b,* and Sérgio L. Pereiraa the ratites (5). Here, we review the phylogenetic relation- aDepartment of Natural Histor y, Royal Ontario Museum, 100 Queen’s ships and divergence times of the extant clades of ratites, Park Crescent, Toronto, ON, Canada; bDepartment of Ecology and the extinct moas and the tinamous. Evolutionary Biology, University of Toronto, Toronto, ON, Canada Longstanding debates about whether the paleognaths *To whom correspondence should be addressed (allanb@rom. are monophyletic or polyphyletic were not settled until on.ca) phylogenetic analyses were conducted on morphological characters (6–9), transferrins (10), chromosomes (11, 12), Abstract α-crystallin A sequences (13, 14), DNA–DNA hybrid- ization data (15, 16), and DNA sequences (e.g., 17–21). The Paleognathae is a monophyletic clade containing ~32 However, relationships among paleognaths are still not species and 12 genera of ratites and 46 species and nine resolved, with a recent morphological tree based on 2954 genera of tinamous. With the exception of nuclear genes, characters placing kiwis (Apterygidae) as the closest rela- there is strong molecular and morphological support for tives of the rest of the ratites (9), in agreement with other the close relationship of ratites and tinamous. Molecular morphological studies using smaller data sets ( 6–8, 22). time estimates with multiple fossil calibrations indicate that DNA sequence trees place kiwis in a derived clade with all six families originated in the Cretaceous (146–66 million the Emus and Cassowaries (Casuariiformes) (19–21, 23, years ago, Ma). The radiation of modern genera and species 24).
    [Show full text]
  • Onetouch 4.0 Scanned Documents
    / Chapter 2 THE FOSSIL RECORD OF BIRDS Storrs L. Olson Department of Vertebrate Zoology National Museum of Natural History Smithsonian Institution Washington, DC. I. Introduction 80 II. Archaeopteryx 85 III. Early Cretaceous Birds 87 IV. Hesperornithiformes 89 V. Ichthyornithiformes 91 VI. Other Mesozojc Birds 92 VII. Paleognathous Birds 96 A. The Problem of the Origins of Paleognathous Birds 96 B. The Fossil Record of Paleognathous Birds 104 VIII. The "Basal" Land Bird Assemblage 107 A. Opisthocomidae 109 B. Musophagidae 109 C. Cuculidae HO D. Falconidae HI E. Sagittariidae 112 F. Accipitridae 112 G. Pandionidae 114 H. Galliformes 114 1. Family Incertae Sedis Turnicidae 119 J. Columbiformes 119 K. Psittaciforines 120 L. Family Incertae Sedis Zygodactylidae 121 IX. The "Higher" Land Bird Assemblage 122 A. Coliiformes 124 B. Coraciiformes (Including Trogonidae and Galbulae) 124 C. Strigiformes 129 D. Caprimulgiformes 132 E. Apodiformes 134 F. Family Incertae Sedis Trochilidae 135 G. Order Incertae Sedis Bucerotiformes (Including Upupae) 136 H. Piciformes 138 I. Passeriformes 139 X. The Water Bird Assemblage 141 A. Gruiformes 142 B. Family Incertae Sedis Ardeidae 165 79 Avian Biology, Vol. Vlll ISBN 0-12-249408-3 80 STORES L. OLSON C. Family Incertae Sedis Podicipedidae 168 D. Charadriiformes 169 E. Anseriformes 186 F. Ciconiiformes 188 G. Pelecaniformes 192 H. Procellariiformes 208 I. Gaviiformes 212 J. Sphenisciformes 217 XI. Conclusion 217 References 218 I. Introduction Avian paleontology has long been a poor stepsister to its mammalian counterpart, a fact that may be attributed in some measure to an insufRcien- cy of qualified workers and to the absence in birds of heterodont teeth, on which the greater proportion of the fossil record of mammals is founded.
    [Show full text]
  • An Update of Wallacels Zoogeographic Regions of the World
    REPORTS To examine the temporal profile of ChC produc- specification of a distinct, and probably the last, 3. G. A. Ascoli et al., Nat. Rev. Neurosci. 9, 557 (2008). tion and their correlation to laminar deployment, cohort in this lineage—the ChCs. 4. J. Szentágothai, M. A. Arbib, Neurosci. Res. Program Bull. 12, 305 (1974). we injected a single pulse of BrdU into pregnant A recent study demonstrated that progeni- CreER 5. P. Somogyi, Brain Res. 136, 345 (1977). Nkx2.1 ;Ai9 females at successive days be- tors below the ventral wall of the lateral ventricle 6. L. Sussel, O. Marin, S. Kimura, J. L. Rubenstein, tween E15 and P1 to label mitotic progenitors, (i.e., VGZ) of human infants give rise to a medial Development 126, 3359 (1999). each paired with a pulse of tamoxifen at E17 to migratory stream destined to the ventral mPFC 7. S. J. Butt et al., Neuron 59, 722 (2008). + 18 8. H. Taniguchi et al., Neuron 71, 995 (2011). label NKX2.1 cells (Fig. 3A). We first quanti- ( ). Despite species differences in the develop- 9. L. Madisen et al., Nat. Neurosci. 13, 133 (2010). fied the fraction of L2 ChCs (identified by mor- mental timing of corticogenesis, this study and 10. J. Szabadics et al., Science 311, 233 (2006). + phology) in mPFC that were also BrdU+. Although our findings raise the possibility that the NKX2.1 11. A. Woodruff, Q. Xu, S. A. Anderson, R. Yuste, Front. there was ChC production by E15, consistent progenitors in VGZ and their extended neurogenesis Neural Circuits 3, 15 (2009).
    [Show full text]
  • GALLEY File # 02TQ
    WILSON BULLETIN Tuesday Aug 17 2004 01:24 PM wils 116_202 Mp_134 Allen Press x DTPro System GALLEY File # 02TQ Wilson Bulletin, 116(2), 2004, pp. 134±145 EFFECTS OF WEATHER ON PARROT GEOPHAGY IN TAMBOPATA, PERU DONALD J. BRIGHTSMITH1 ABSTRACT.ÐGeophagy is widespread and well documented for mammals, but avian geophagy has only recently become the subject of serious scienti®c investigation. I analyzed data from 606 mornings of observations at a large avian geophagy site or ``clay lick'' in the southwestern Amazon Basin to examine the effects of weather on bird lick use. Birds used the clay lick on 94% of the mornings without precipitation or fog. Parrots dominated the site in both numbers of species (17) and individuals (.99%). Weather conditions were signi®- cantly correlated with total lick use: there was greater use on sunny mornings and less on rainy mornings. Fog and overnight rain were correlated with low lick use. Sun, rain, fog, and overnight rain were recorded on 47, 25, 20 and 8% of the mornings, respectively. I estimated that inclement weather caused an annual 29% reduction in geophagy for all bird species combined. When early morning rain prevented species from using the lick, they did not return later in the day nor did they compensate for rainy mornings by increasing lick use on subsequent days. The timing of lick use and the lack of compensation suggest that neutralization of toxins could be driving lick use in this system. Received 25 August 2003, accepted 26 May 2004. Geophagy, the intentional consumption of parrots (Psittaciformes), which gather by the soil, is widespread among vertebrate and in- hundreds to consume clay-rich soils from riv- vertebrate taxa including mammals, birds, rep- erbank sites in South America (Emmons and tiles, and insects (Sokol 1971, Arms et al.
    [Show full text]
  • BIO 456/585 Fall 2015 Ornithology UNCW ORDERS and FAMILIES
    BIO 456/585 Fall 2015 Ornithology UNCW ORDERS AND FAMILIES OF BIRDS The following is a list of nearly all Orders of birds, but not all North American families. This classification will be used in this course, but you will see different classifications in the literature. You will be expected to know all the orders and families shown here. This list follows the American Ornithologists’ Union (A.O.U.) 1998 classification plus supplements since that time. Superorder Palaeognathae (ratites) Struthioniformes Struthionidae – ostriches Rheiformes Rheidae – rheas Casuariiformes Casuariidae – emus and cassowaries Dinornithiformes Apterygidae – kiwis Tinamiformes Tinamidae – tinamous Superorder Neognathae Gaviiformes Gaviidae – loons Podicipediformes Podicipedidae – grebes Procellariformes Diomedeidae – albatrosses Procellaridae – shearwaters, fulmars, and petrels Hydrobatidae – storm-petrels Sphenisciformes Spheniscidae – penguins Pelecaniformes Sulidae – boobies and gannets Pelecanidae – pelicans Phalacrocoracidae – cormorants Anhingidae – anhingas Fregatidae – frigatebirds Ciconiiformes Ardeidae – herons and bitterns Threskiornithidae – ibises and spoonbills Ciconiidae – storks Cathartidae (Vulturidae) – vultures Phoenicopteriformes Phoenicopteridae – flamingos Anseriformes Anatidae – swans, geese, ducks Falconiformes (Accipitriformes) Accipitridae – kites, eagles, hawks Falconidae – caracaras and falcons Galliformes Phasianidae – grouse, turkey, and pheasants Odontophoridae – New World quail Gruiformes Rallidae – rails Gruidae – cranes Charadriiformes
    [Show full text]
  • The Bony Palate of Birds. Part I the Palaeognathae
    520 McDowaLL,Bony Palate of Birds [AukLOct. MIRANDA RIBEIRO, PAULO DE 1929. Da nidifica•o de Chaetura½inereiventris. Bol. Mus. Nac. [Rio], 4: 101-105. RIDGWAY, R. 1911. The birds of North and Middle America. Bull. U.S. Nat. Mus., 50 (5): 684. Stcx, H. 1947a. O ninho de Panyptila cayennehals(Gmelin) e algumas observag6escom- pilat6rias s6bre a ecologiade outros andorinh6esBrasileiros. Rev. Bras. Biologla, 7: 219-246. 1947b. The nesting of Reinarda squamata(Cassin). The Auk, 65 (2): 169-174, pl. 6. WI•)-N•vw•), Paz•z Mix. zv 1821. Reise nach Brasilien, 2: ?$. 1850. Beitraege zur Kenntnls der Vogelwelt Brasiliens,5: 347-$51. Fu•da•5o Brasil Ceutral Av. Nilo Pelauha 25 Rio de Jauei•o, Brazil THE BONY PALATE OF BIRDS. PART I THE PALAEOGNATHAE BY SAM MCDOWELL Tins is the first in a seriesof papers in which the author intends to describe the osteologyof the known birds with the end in mind of throwing morelight on their highersystematics. I have chosenas my first topic the bony palate becauseof the stresslaid upon this part of the avian skeletonfrom Cornay to the present in the classification of birds. ACKNOWLEDGMENTS The author is deeply indebted to Dr. Ernst Mayr of the American Museum of Natural History for his generousencouragement and wise advice;to Dr. GeorgeGaylord Simpson,Curator of FossilMammals and Birds of the same institution, for his invaluable suggestionsand commentaries on the preliminary draft of this paper; to Mr. R. deSchauenseeand Mr. James Bond of the Academy of Natural Sciencesof Philadelphiafor generouslyallowing the author the use of the Academy's skeletal material; to Messrs.
    [Show full text]
  • Dinosaurs! Pdf, Epub, Ebook
    DINOSAURS! PDF, EPUB, EBOOK Gail Gibbons | 32 pages | 05 Mar 2009 | Holiday House | 9780823421978 | English | New York, NY, United States Dinosaurs! PDF Book Comment and Reply. There is general agreement that some behaviors that are common in birds, as well as in crocodiles birds' closest living relatives , were also common among extinct dinosaur groups. Anchiornis - A four-winged dino-bird that resembled Microraptor. Let us know if you have suggestions to improve this article requires login. Dinosaur legs extend directly beneath the body, whereas the legs of lizards and crocodilians sprawl out to either side. November—December It has been suggested that because small mammals, squamata and birds occupied the ecological niches suited for small body size, non-avian dinosaurs never evolved a diverse fauna of small-bodied species, which led to their downfall when large-bodied terrestrial tetrapods were hit by the mass extinction event. They were wrong. New York: W. This dinosaur was likely resting in a burrow before it was abruptly buried alive. The earliest part of this time saw the spread of ankylosaurians, iguanodontians , and brachiosaurids through Europe , North America, and northern Africa. Edward Drinker Cope. Sinoceratops - A rare ceratopsian from late Cretaceous China. The battle of the sourpusses! Denisovans are an extinct species of hominid and a close relative to modern humans. Dutton , ; London : Evans Brothers Ltd , ]. Anatosaurus - This dinosaur is now known as either Anatotitan or Edmontosaurus. One of the best examples of soft-tissue impressions in a fossil dinosaur was discovered in the Pietraroia Plattenkalk in southern Italy. Neanderthals are an extinct species of hominids that were the closest relatives to modern human beings.
    [Show full text]
  • Husbandry Guidelines For
    Kelly Swarbrick 1068 Certificate III in Captive Animals 16/11/09 RUV30204 Husbandry Guidelines for Kelly Swarbrick 2008 Emus Dromaius novaehollandiae Aves: Casuariidae Compiler: Kelly Swarbrick th Date of Preparation: 16 November 2009 Western Sydney Institute of TAFE, Richmond Course Name: Certificate III in Captive Animals Course Number: 1068 Lecturers: Graeme Phipps, Jacki Salkeld, and Brad Walker 1 Kelly Swarbrick 1068 Certificate III in Captive Animals 16/11/09 RUV30204 DISCLAIMER This Emu Husbandry Manual is intended to present the current scientific, experiential and practical understanding of the captive care of Emus. Some contributions lend themselves to scientific rigor, where material presented is supported by peer-reviewed literature. Other contributions are based, out of necessity, on the collective experience of professional keepers, because relevant scientific literature is scant or non-existent. The author cannot be, and is not, legally, financially or in any other way, responsible for the application of techniques described within the Manual. When undertaking any procedures or techniques outlined in the Manual, it is up to individual workers to assess the unique circumstances of their situation, apply common sense, and subsequently apply any procedures or techniques at their own risk. In all cases, the reader of this Manual is cautioned not to use this manual as an exact step-by-step guide, but rather as a starting reference point for further case-specific studies. 2 Kelly Swarbrick 1068 Certificate III in Captive Animals 16/11/09 RUV30204 OCCUPATIONAL HEALTH AND SAFETY RISKS Exhibiting Emus falls under the medium risk category (hazardous). This is due to their powerful legs that could deliver a nasty kick.
    [Show full text]
  • The Mechanics of Terrestrial Locomotion and the Function and Evolutionary History Of
    The Mechanics of Terrestrial Locomotion and the Function and Evolutionary History of Head-bobbing in Birds A dissertation presented to the faculty of the College of Arts and Sciences of Ohio University In partial fulfillment of the requirements for the degree Doctor of Philosophy Jennifer Ann Hancock August 2010 © 2010 Jennifer Ann Hancock. All Rights Reserved. 2 This dissertation titled The Mechanics of Terrestrial Locomotion and the Function and Evolutionary History of Head-bobbing in Birds by JENNIFER ANN HANCOCK has been approved for the Department of Biological Sciences and the College of Arts and Sciences by ___________________________________________ Audrone R. Biknevicius Associate Professor of Biomedical Sciences ___________________________________________ Benjamin M. Ogles Dean, College of Arts and Sciences 3 ABSTRACT Hancock, Jennifer Ann, Ph.D., August 2010, Biological Sciences The Mechanics of Terrestrial Locomotion and the Function and Evolutionary History of Head-bobbing in Birds (194 pp.) Director of Dissertation: Audrone R. Biknevicius Head-bobbing is the fore-aft movement of the head exhibited by some birds during terrestrial locomotion. It is primarily considered to be a response to enhance vision. This has led some researchers to hypothesize that head-bobbing should be found in birds that are visual foragers and may be correlated with the morphology of the retina. In contrast, other researchers suggest that head-bobbing is mechanically linked to the locomotor system and that its visual functions are secondarily adapted. This dissertation explored the mechanics of terrestrial locomotion and head- bobbing of birds in both the lab and field. In the lab, the kinetics and kinematics of terrestrial locomotion in the Elegant Crested Tinamous (Eudromia elegans) were analyzed using high-speed videography and ground reaction forces.
    [Show full text]
  • Rheiformes ~ Tinamiformes ~ Apterygiformes ~ Casuariiformes
    Birds of the World part 1 Paleognaths PALAEOGNATHAE • ORDER STRUTHIONIFORMES – Family Struthionidae – ostriches (2 species) • ORDER RHEIFORMES – Family Rheidae – rheas (2 species) • ORDER TINAMIFORMES – Family Tinamidae – tinamous (47 species) • ORDER APTERYGIFORMES – Family Apterygidae – kiwis (5 species) • ORDER CASUARIIFORMES – Family Casuariidae – cassowaries (3 species) – Family Dromaiidae – emu (1 species) PALAEOGNATHAE • ORDER STRUTHIONIFORMES – Family Struthionidae – ostriches (2 species) • ORDER RHEIFORMES – Family Rheidae – rheas (2 species) • ORDER TINAMIFORMES – Family Tinamidae – tinamous (47 species) • ORDER APTERYGIFORMES – Family Apterygidae – kiwis (5 species) • ORDER CASUARIIFORMES – Family Casuariidae – cassowaries (3 species) – Family Dromaiidae – emu (1 species) ostrich (Struthioniformes) PALAEOGNATHAE • ORDER STRUTHIONIFORMES – Family Struthionidae – ostriches (2 species) • ORDER RHEIFORMES – Family Rheidae – rheas (2 species) • ORDER TINAMIFORMES – Family Tinamidae – tinamous (47 species) • ORDER APTERYGIFORMES – Family Apterygidae – kiwis (5 species) • ORDER CASUARIIFORMES – Family Casuariidae – cassowaries (3 species) – Family Dromaiidae – emu (1 species) greater rhea (Rheiformes) PALAEOGNATHAE • ORDER STRUTHIONIFORMES – Family Struthionidae – ostriches (2 species) • ORDER RHEIFORMES – Family Rheidae – rheas (2 species) • ORDER TINAMIFORMES – Family Tinamidae – tinamous (47 species) • ORDER APTERYGIFORMES – Family Apterygidae – kiwis (5 species) • ORDER CASUARIIFORMES – Family Casuariidae – cassowaries (3 species)
    [Show full text]
  • The Avian Cecum: a Review
    Wilson Bull., 107(l), 1995, pp. 93-121 THE AVIAN CECUM: A REVIEW MARY H. CLENCH AND JOHN R. MATHIAS ’ ABSTRACT.-The ceca, intestinal outpocketings of the gut, are described, classified by types, and their occurrence surveyed across the Order Aves. Correlation between cecal size and systematic position is weak except among closely related species. With many exceptions, herbivores and omnivores tend to have large ceca, insectivores and carnivores are variable, and piscivores and graminivores have small ceca. Although important progress has been made in recent years, especially through the use of wild birds under natural (or quasi-natural) conditions rather than studying domestic species in captivity, much remains to be learned about cecal functioning. Research on periodic changes in galliform and anseriform cecal size in response to dietary alterations is discussed. Studies demonstrating cellulose digestion and fermentation in ceca, and their utilization and absorption of water, nitrogenous com- pounds, and other nutrients are reviewed. We also note disease-causing organisms that may be found in ceca. The avian cecum is a multi-purpose organ, with the potential to act in many different ways-and depending on the species involved, its cecal morphology, and ecological conditions, cecal functioning can be efficient and vitally important to a birds’ physiology, especially during periods of stress. Received 14 Feb. 1994, accepted 2 June 1994. The digestive tract of most birds contains a pair of outpocketings that project from the proximal colon at its junction with the small intestine (Fig. 1). These ceca are usually fingerlike in shape, looking much like simple lateral extensions of the intestine, but some are complex in struc- ture.
    [Show full text]