The Origin of Birds and Flight Ticular Purpose
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The Origin and Early Evolution of Dinosaurs
Biol. Rev. (2010), 85, pp. 55–110. 55 doi:10.1111/j.1469-185X.2009.00094.x The origin and early evolution of dinosaurs Max C. Langer1∗,MartinD.Ezcurra2, Jonathas S. Bittencourt1 and Fernando E. Novas2,3 1Departamento de Biologia, FFCLRP, Universidade de S˜ao Paulo; Av. Bandeirantes 3900, Ribeir˜ao Preto-SP, Brazil 2Laboratorio de Anatomia Comparada y Evoluci´on de los Vertebrados, Museo Argentino de Ciencias Naturales ‘‘Bernardino Rivadavia’’, Avda. Angel Gallardo 470, Cdad. de Buenos Aires, Argentina 3CONICET (Consejo Nacional de Investigaciones Cient´ıficas y T´ecnicas); Avda. Rivadavia 1917 - Cdad. de Buenos Aires, Argentina (Received 28 November 2008; revised 09 July 2009; accepted 14 July 2009) ABSTRACT The oldest unequivocal records of Dinosauria were unearthed from Late Triassic rocks (approximately 230 Ma) accumulated over extensional rift basins in southwestern Pangea. The better known of these are Herrerasaurus ischigualastensis, Pisanosaurus mertii, Eoraptor lunensis,andPanphagia protos from the Ischigualasto Formation, Argentina, and Staurikosaurus pricei and Saturnalia tupiniquim from the Santa Maria Formation, Brazil. No uncontroversial dinosaur body fossils are known from older strata, but the Middle Triassic origin of the lineage may be inferred from both the footprint record and its sister-group relation to Ladinian basal dinosauromorphs. These include the typical Marasuchus lilloensis, more basal forms such as Lagerpeton and Dromomeron, as well as silesaurids: a possibly monophyletic group composed of Mid-Late Triassic forms that may represent immediate sister taxa to dinosaurs. The first phylogenetic definition to fit the current understanding of Dinosauria as a node-based taxon solely composed of mutually exclusive Saurischia and Ornithischia was given as ‘‘all descendants of the most recent common ancestor of birds and Triceratops’’. -
Stable Structural Color Patterns Displayed on Transparent Insect Wings
Stable structural color patterns displayed on transparent insect wings Ekaterina Shevtsovaa,1, Christer Hanssona,b,1, Daniel H. Janzenc,1, and Jostein Kjærandsend,1 aDepartment of Biology, Lund University, Sölvegatan 35, SE-22362 Lund, Sweden; bScientific Associate of the Entomology Department, Natural History Museum, London SW7 5BD, United Kingdom; cDepartment of Biology, University of Pennsylvania, Philadelphia, PA 19104-6018; and dDepartment of Biology, Museum of Zoology, Lund University, Helgonavägen 3, SE-22362 Lund, Sweden Contributed by Daniel H. Janzen, November 24, 2010 (sent for review October 5, 2010) Color patterns play central roles in the behavior of insects, and are and F). In laboratory conditions most wings are studied against a important traits for taxonomic studies. Here we report striking and white background (Fig. 1 G, H, and J), or the wings are embedded stable structural color patterns—wing interference patterns (WIPs) in a medium with a refractive index close to that of chitin (e.g., —in the transparent wings of small Hymenoptera and Diptera, ref. 19). In both cases the color reflections will be faint or in- patterns that have been largely overlooked by biologists. These ex- visible. tremely thin wings reflect vivid color patterns caused by thin film Insects are an exceedingly diverse and ancient group and interference. The visibility of these patterns is affected by the way their signal-receiver architecture of thin membranous wings the insects display their wings against various backgrounds with and color vision was apparently in place before their huge radia- different light properties. The specific color sequence displayed tion (20–22). The evolution of functional wings (Pterygota) that lacks pure red and matches the color vision of most insects, strongly can be freely operated in multidirections (Neoptera), coupled suggesting that the biological significance of WIPs lies in visual with small body size, has long been viewed as associated with their signaling. -
Why Much of What We Teach About Evolution Is Wrong/By Jonathan Wells
ON SCIENCE OR MYTH? Whymuch of what we teach about evolution is wrong Icons ofEvolution About the Author Jonathan Wells is no stranger to controversy. After spending two years in the U.S. Ar my from 1964 to 1966, he entered the University of California at Berkeley to become a science teacher. When the Army called him back from reser ve status in 1968, he chose to go to prison rather than continue to serve during the Vietnam War. He subsequently earned a Ph.D. in religious studies at Yale University, where he wrote a book about the nineteenth century Darwinian controversies. In 1989 he returned to Berkeley to earn a second Ph.D., this time in molecular and cell biology. He is now a senior fellow at Discovery Institute's Center for the Renewal of Science and Culture (www.discovery.org/ crsc) in Seattle, where he lives with his wife, two children, and mother. He still hopes to become a science teacher. Icons ofEvolution Science or Myth? Why Much oJWhat We TeachAbout Evolution Is Wrong JONATHAN WELLS ILLUSTRATED BY JODY F. SJOGREN IIIIDIDIREGNERY 11MPUBLISHING, INC. An EaglePublishing Company • Washington, IX Copyright © 2000 by Jonathan Wells All rights reserved. No part of this publication may be reproduced or trans mitted in any form or by any means electronic or mechanical, including pho tocopy, recording, or any information storage and retrieval system now known or to be invented, without permission in writing from the publisher, except by a reviewer who wishes to quote brief passages in connection with a review written for inclusion in a magazine, newspaper, or broadcast. -
Consequences of Evolutionary Transitions in Changing Photic Environments
bs_bs_banner Austral Entomology (2017) 56,23–46 Review Consequences of evolutionary transitions in changing photic environments Simon M Tierney,1* Markus Friedrich,2,3 William F Humphreys,1,4,5 Therésa M Jones,6 Eric J Warrant7 and William T Wcislo8 1School of Biological Sciences, The University of Adelaide, North Terrace, Adelaide, SA 5005, Australia. 2Department of Biological Sciences, Wayne State University, 5047 Gullen Mall, Detroit, MI 48202, USA. 3Department of Anatomy and Cell Biology, Wayne State University, School of Medicine, 540 East Canfield Avenue, Detroit, MI 48201, USA. 4Terrestrial Zoology, Western Australian Museum, Locked Bag 49, Welshpool DC, WA 6986, Australia. 5School of Animal Biology, University of Western Australia, Nedlands, WA 6907, Australia. 6Department of Zoology, The University of Melbourne, Melbourne, Vic. 3010, Australia. 7Department of Biology, Lund University, Sölvegatan 35, S-22362 Lund, Sweden. 8Smithsonian Tropical Research Institute, PO Box 0843-03092, Balboa, Ancón, Republic of Panamá. Abstract Light represents one of the most reliable environmental cues in the biological world. In this review we focus on the evolutionary consequences to changes in organismal photic environments, with a specific focus on the class Insecta. Particular emphasis is placed on transitional forms that can be used to track the evolution from (1) diurnal to nocturnal (dim-light) or (2) surface to subterranean (aphotic) environments, as well as (3) the ecological encroachment of anthropomorphic light on nocturnal habitats (artificial light at night). We explore the influence of the light environment in an integrated manner, highlighting the connections between phenotypic adaptations (behaviour, morphology, neurology and endocrinology), molecular genetics and their combined influence on organismal fitness. -
ID Lecture 7 Fossils 2014
Intelligent Design vs. Evolution Defending God’s Creation Genesis 1:1, 21, 25 1 In the beginning God created the heavens and the earth ! 21 So God created great sea creatures and every living thing that moves, with which the waters abounded, according to their kind, and every winged bird according to its kind. And God saw that it was good. ! 25 And God made the beast of the earth according to its kind, cattle according to its kind, and everything that creeps on the earth according to its kind. And God saw that it was good. Intelligent Design Critics “The argument for intelligent design basically depends on saying, ‘You haven’t answered every question with evolution.’ Well, guess what? Science can’t answer every question.” ! Kenneth Miller Brown University biologist Houston Chronicle, 10-22-05 Fossilization • Animal or plant must be buried quickly – Catastrophic event – Before decay or consumed • Buried with right mixture of minerals – Everything is replaced slowly with minerals and becomes hard as rock ! • Study of fossils is paleontology Nested Hierarchy • Biology classification developed by Carolus Linnaeus (pre-Darwin) • Organisms grouped by similarities and differences Humans Kingdom Animals Phylum Chordates Class Mammals Order Primates Family Hominids Genus Homo Species sapiens Fossil Record • Cambrian Explosion – “Biology’s Big Bang” • Transitional Fossils – Archaeopteryx • Reptile to mammal evolution • Whale evolution • Fish to Amphibian evolution Characteristics of Fossil Record ! • Sudden Appearance (Saltation) ! • Stasis ! • -
Archaeoraptor Liaoningensis
Luke 19 39 And some of the Pharisees from among the multitude said unto him, Master, rebuke thy disciples. 40 And he answered and said unto them, I tell you that, if these should hold their peace, the stones would immediately cry out. ©2000 Timothy G. Standish The Fossil Record Timothy G. Standish, Ph. D. ©2000 Timothy G. Standish Missing Links and the Fossil Record "But just in proportion as this process of extermination has acted on an enormous scale, so must the number of intermediate varieties, which have formerly existed, be truly enormous. Why then is not every geological formation and every stratum full of such intermediate links? Geology assuredly does not reveal any such finely graduated organic chain; and this, perhaps, is the most obvious and serious objection which can be urged against the theory. The explanation lies, as I believe, in the extreme imperfection of the geological record.” Darwin C.R. 1872. The Origin of Species by Means of Natural Selection. “Ancient rocks clearly preserve less information, on average, than more recent rocks. However, if scaled to the stratigraphic level of the stage and the taxonomic level of the family, the past 540 million years of the fossil record provide uniformly good documentation of the life of the past.” ©2000 Timothy G. Standish M J Benton M A Wills & R Hitchin 2000 Quality of the fossil record through time What is a Fossil? Six major types: z Preserved organisms - The most uncommon fossils, including insects in amber, frozen mammoths, organisms preserved in peat bogs and tar pits z Preserved hard parts - Teeth, bones, shells or other hard parts that have been preserved over time z Impressions - Flattened outlines of the surface of an organism, frequently carbonized z Molds - After an organism has been surrounded by mud which turns to rock, the remains leech out of the rock, leaving only the mold z Casts - Molds that have been filled with another material after the remains have been removed produce casts z Trace fossils - Tracks burrows and other evidence of life left in the rock ©2000 Timothy G. -
PRISCUM the Newsletter of the Paleontological Society Volume 13, Number 2, Fall 2004
PRISCUM The Newsletter of the Paleontological Society Volume 13, Number 2, Fall 2004 Paleontological PRESIDENT’S Society Officers COLUMN: Inside... President Treasurer’s Report 2 William I. Ausich WE NEED YOU! GSA Information 2 President-Elect by William I. Ausich Reviews of PS- David Bottjer Sponsored Sessions 3 Past-President Why are you a member of The Paleontology Portal 5 Patricia H. Kelley The Paleontological Society? In PS Lecture Program 6 Secretary the not too distance past, the Books for Review 9 Roger D. K. Thomas only way to receive a copy of the Journal of Book Reviews 9 Treasurer Paleontology and Paleobiology was to pay your dues Conference Announce- and belong to the Society. I suppose one could Mark E. Patzkowsky have borrowed a copy from a friend or wander over ments 14 JP Managing Editors to the library. However, this was probably done Ann (Nancy) F. Budd with a heavy burden of guilt. Now, as we move Christopher A. Brochu into the digital age of scientific journal publishing, Jonathan Adrain one can have copies of the Journal of Paleontology and Paleobiology transmitted right to your Paleobiology Editors computer. It actually may arrive faster than the Tomasz Baumiller U.S. mail, you do not have to pay anything, and Robyn Burnham you do not even have to walk over to the library. Philip Gingerich No need for shelf space, no hassle, no dues, no Program Coordinator guilt – isn’t the Web great? The Web is great, but the Society needs dues-paying members in order Mark A. Wilson to continue to publish in paper, digitally, or both. -
The Archaeoraptor Forgery
brief communications Pattern and intensity of physical activity Keeping moderately active is the best way to boost total daily energy expenditure. low level of physical activity is a per- 2.2 taining energy balance and may lose weight; vasive feature of our modern lifestyle. PAL is about 1.5 or 2.1 for sedentary or very Attempts to counteract the negative active people, respectively5. My results indi- A 2.0 effects of sedentary living include introduc- cating that short periods of vigorous activi- ing bouts of high-intensity exercise, but I ty do not have much impact on PAL in the 1.8 show here that it can be more effective to PAL normal population are borne out by studies increase the amount of time spent on activ- on obese patients: adding exercise to an ities of moderate intensity while reducing 1.6 energy-restricted diet does not further periods of inactivity during waking hours. increase weight loss6,7 because the costs of 1.4 Physical inactivity may be associated not 02040 60 80 100 the extra activity are compensated by a only with being overweight but also with Fraction of daytime (%) reduction of energy spent on physical activ- disorders such as coronary heart disease or ity outside the training sessions8. type-2 diabetes1, which may be prevented Figure 1 Physical activity levels (PAL) as a function of the fraction My results show, however, that the pro- by exercising regularly2. Consequently, of daytime hours spent by 30 healthy subjects (with body-mass portion of time distributed between activi- sedentary people often include spells of vig- indices within the normal range) on activities of low (filled circles), ties of low and moderate intensity is what orous exercise in an otherwise inactive and moderate (circles) and high (squares) exercise intensity. -
See a Color Pdf of This Month's Issue Here
Newsletter of the University of California Museum of Paleontology UCMP NEWS JAN 2013 New species from the drawers of UCMP A frequent question we get at the museum is whether all our fossils are described. We can assure you there are many, many left to be described, and every year many scientists de- scribe new species and do new research based on fossils they find in our drawers. In 2012, UCMP vertebrate fossils were used in 81 published studies by scientists from around Courtesy of Erica Clites Courtesy of Jason Carr the world, and 13 new taxa were named Erica working on 550-million-year-old fossils Jason sits beside a jacket containing the jaw- from previously undescribed specimens. in the Ediacaran Hills of South Australia bone of a Miocene amphicyonid representing Here’s the new taxa roundup for 2012. while a master’s student in Mary Droser’s lab the largest and most complete fossil carnivoran January—UC alum Samantha Hopkins at UC Riverside. yet recovered in Panama. and her student Jonathan Calede1 described Hesperogaulus shotwelli, a new species of New Museum Scientist Meet Jason Carr, the new horned rodent from Nevada in the Zoologi- Erica Clites to manage fossil preparation lab cal Journal of the Linnean Society. USGS fossil collection manager March—Recent UC graduate Brian 2 Growing up in Ann Arbor, Michigan, Erica Jason Carr grew up along the Central Coast Swartz named Tinirau clackae, a stem tet- Clites says her early training as a scien- of California, in Santa Maria, surrounded rapod from Nevada Devonian in PLoS One. -
The Development of a Miniature Mechanism for Producing Insect Wing Motion
The development of a miniature mechanism for producing insect wing motion S. C. Burgess, K. Alemzadeh & L. Zhang Department of Mechanical Engineering, Bristol University, Bristol, UK Abstract Insects are capable of very agile flight on a small scale. If a man-made machine can be built that can fly like an insect, it would have important industrial, civil and military applications. Insects have complex wing motions including non- planar wing strokes and stroke reversal. This paper presents the design of a novel mechanism which can produce insect type wing motion. The mechanism is very light and compact and has potential for use in micro air vehicles. A prototype has been built and some preliminary tests have been carried out to characterize the mechanism performance. Keywords: insect flight, wing motion, novel mechanisms, wing reversal, lift. 1 Introduction The ability for controlled flight has existed in at least four classes of creature: (1) birds; (2) mammals (bats); (3) reptiles (pterosaurs); and (4) insects. Pterosaurs are believed to have been the largest fliers with wingspans up to 12m. It is thought that pterosaurs were capable of flapping flight because fossil records show a similar type of shoulder joint to that found in birds. Birds currently have a large range of size from the large albatross with a wingspan of up to 3.5m, to the tiny bumble hummingbird which has a span of only 8cm. Most birds can perform flapping flight but not true hovering flight. However, hummingbirds have a flexible shoulder joint which enables them to hover in windless conditions. Bats have a relatively small range of size. -
Kevin Padian
Palaeontologia Electronica http://palaeo-electronica.org/ FEATHERS, FAKES, AND FOSSIL DEALERS: HOW THE COMMERCIAL SALE OF FOSSILS ERODES SCIENCE AND EDUCATION Kevin Padian A false and a true tail true. Farmers in the Liaoning Province of China, from where this fossil and many others (including The November 1999 issue of National Geo- the feathered dinosaurs) come, often put together graphic carried an article by Art Editor Chris Sloan naturally unassociated body parts, and will carve entitled "Feathers on T. rex?" It was a follow-up of other features, in order to make the specimens a successful feature that had appeared in the July more attractive and potentially more valuable. 1998 issue about the new feathered dinosaurs "Archaeoraptor" apparently has turned out to from China, and what they tell us about the origin be such a chimera. This is based on computer- of birds, of feathers, and of flight. The premise of tomographic (CT) analysis that had evidently been the T. rex article was simple enough. True feathers done at the time but was not accepted by all those or fine, filamentous integumentary structures working on the specimen (results of the analysis (sometimes both) have been found in a variety of are still unpublished). This specimen had been pur- coelurosaurian theropod dinosaurs, from the basal chased for the small Dinosaur Museum in Bland- compsognathids to the dromaeosaurs (generally ings, Utah, by a backer of that museum. It came regarded as the closest sister-taxon to birds). So it from that legendary fossil site, the Tucson Gem seems conservative to infer that tyrannosaurs, and Mineral Show, where unadulterated speci- which are now recognized as overgrown coeluro- mens from all over the world are sold alongside saurs, may have had a similar integumentary cov- many that are enhanced, and the action in hotel ering, at least at some point in their lives. -
Quick Estimates of Flight Fitness in Hovering Animals, Including Novel Mechanisms for Lift Production
7. Exp. Biol. (1973). 59. 169-230 l6g With 23 text-figures Printed in Great Britain QUICK ESTIMATES OF FLIGHT FITNESS IN HOVERING ANIMALS, INCLUDING NOVEL MECHANISMS FOR LIFT PRODUCTION BY TORKEL WEIS-FOGH Department of Zoology, Cambridge CBz ^EJ, England (Received 11 January 1973) INTRODUCTION In a recent paper I have analysed the aerodynamics and energetics of hovering hummingbirds and DrosophUa and have found that, in spite of non-steady periods, the main flight performance of these types is consistent with steady-state aerodynamics (Weis-Fogh, 1972). The same may or may not apply to other flapping animals which practise hovering or slow forward flight at similar Reynolds numbers (Re), ioa to io*. As discussed in that paper, there are of course non-steady flow situations at the start and stop of each half-stroke of the wings. Moreover, it does not follow that all hovering animals make use mainly of steady-state principles. It is therefore desirable to obtain as simple and as easily analytical expressions as possible which should make it feasible to estimate the forces on the wings and the work and power produced. In this way one may make use of the large number of observations on freely flying animals to be found in the scattered literature. It may then be possible to identify the deviating groups and to approach the problems in a new way. This is the main purpose of the present studies, which both include new material and provide novel solutions. Major emphasis must be placed on simplicity. This involves approximations since the true flight system is so complicated as to be unmanageable.